safety related words

Personal Protective Equipment (PPE) : Equipment provided to shield or isolate a person from the chemical, physical, and thermal hazards that may be encountered at a hazardous materials incident. Adequate personal protective equipment should protect the respiratory system, skin, eyes, face, hands, feet, head, body, and hearing. Personal protective equipment includes: personal protective clothing, self-contained positive pressure breathing apparatus, and air purifying respirators.

Mitigation: Any offensive or defensive action to contain, control, reduce, or eliminate the harmful effects of a hazardous materials release.
Monitoring

The act of systematically checking to determine contaminant levels and atmospheric conditions.

Monitoring Instruments

Combustible Gas Indicator (CGI): Measures the concentration of a combustible gas or vapor in air.

Flammable Limits

(Note to reader: The terms flammable limits and explosive limits are often used interchangeably. Within the propane industry, the term flammable limits is used most often in technical literature. Within the emergency services, the term explosive limit is most common. Both terms have the same meaning.) Flammable limits are the range of gas or vapor concentration (percentage by volume in air) that will burn or explode if an ignition source is present. Limiting concentrations are commonly called the "lower flammable limit" and the "upper flammable limit." Below the lower flammable limit, the mixture is too lean to burn; above the upper flammable limit, the mixture is too rich to burn. If the gas or vapor is released into an oxygen-enriched atmosphere, the flammable range will expand. Likewise, if the gas or vapor is released into an oxygen-deficient atmosphere, the flammable range will contract.

Oxygen Monitor: Measures the percentage of oxygen in air.

Colorimetric Indicator Tube: Measures the concentration of specific gases and vapors in air.

Specific Chemical Monitor: Designed to detect a large group of chemicals or a specific chemical. Most common examples include carbon monoxide and hydrogen sulfide.

Flame Ionization Detector (FID): A device used to determine the presence of organic vapors and gases in air. Operates in two modes& emdash;survey mode and gas chromatograph.

Gas Chromatograph: An instrument used for identifying and analyzing specific organics compounds.

Photoionization Detector (PID): A device used to determine the total concentration of many organic and some inorganic gases and vapors in air.

Radiation Monitor: An instrument used to measure accumulated radiation exposure. Include both alpha, beta, and gamma survey detectors.

Radiation Dosimeter Detector: An instrument which measures the dose of radiation to which a person has been exposed.

Corrosivity (pH) Detector: A meter, paper, or strip that indicates the relative acidity or alkalinity of a substance, generally using an international scale of 0 (acid) through 14 (alkali-caustic). (See pH.)

Indicator Paper: Special chemical indicating papers which test for the presence of specific hazards, such as oxidizers, organic peroxides, and hydrogen sulfide. Are usually part of a hazmat identification system.

Accident An undesired event resulting in death, injury, or damage to health

Acute Immediate effect

Allergen Substance causing an adverse (usually to lungs or skin) reaction in a person who is sensitive to that substance

Appointed Person A person who has been nominated to take charge in the event of an accident, fire or illness.

Approved Code of Practice A code of practice, associated with specific regulations, that has been approved by the Health & Safety Commission, that has power like the Highway Code

Asbestos Magnesium silicate in fibrous form responsible for 3000 deaths a year in UK

Awarding Body is national organisation with powers to accedit and award qualifications.

Carcinogen Substance that causes cancer

Carpal Tunnel Syndrome A chronic disorder of the hand and wrist often due to repetitive work involving repeated wrist flexion or extension

Chronic Occurring over a period of time

Code of Practice Rules established by regulatory bodies or trade associations, which are intended as a guide to acceptable behaviour. As such they do not have the force of law behind them

Common Law "Judge-made" law that is not written in statute

Competent Person A person who is appropriately trained, qualified, experienced and skilled to undertake specific health and safety duties suchas a risk assessment

Compliance The act or process of fulfilling requirements

Control of Substances Hazardous to Health Regulations (COSHH) promoting safe working with potentially hazardous chemicals

Designated Person A person who has been designated as a first aider at work and has been trained to have the knowledge and confidence to deal with any first aid emergency (See Appointed Person)

Dose The amount of substance to which a person is exposed in terms of the concentration of the substance and the time period during which the exposure occurs

Ergonomics The science and technology of designing equipment, tools, work tasks to fit people.

Hazard Potential for harmful effects

Health And Safety Executive UK Organisation responsible for proposing and enforcing safety statutes, regulations, approved codes of practice and guidance.
Illuminance A measure of the amount of light falling on a particular point, measured in Lux

"Health and safety practices are those actions and procedures at work that promote better health and safety".

"Health & Safety Skills are H&S  practices implemented according to national standards competence". This is our working definition, but would welcome other suggestions.

Improvement Notice A statutory notice that is issued by an authorising body such as Health and Safety Executive (HSE), Environmental Health Officer (EHO) or Fire Officer on discovery of a breach of statute. It states the offence committed, what action needs to be taken and the time deadline to take action.

Incident (or Near Miss) An event that did not cause harm but which might have done so under different circumstances

Ingestion Taking a substance into the body through the mouth, e.g. food or drink

Inhalation Taking a substance into the body by breathing it in, e.g. gases, fumes, vapours, mists, aerosols or dusts,

Irritant A substance that produces inflammation when it makes contacts with the skin, eyes, nose, or respiratory system

Material Data Safety Sheet Contain information on the hazards associated with a chemical, along with guidance on its safe use

Negligence Either 1) omission to do something that a reasonable person would do or 2) commission of some act that a prudent and reasonable person would not do.

Persistence Remaining for an extended period of time. Applicable to some chemicals (e.g. PCBs) that do not easily break down into less hazardous substances

Parts Per Million (ppm) Specifies the concentration by volume of a substance dispersed in another substance

Permit to Work Formally delivered criteria, usually through written procedures, for control/risk reduction when undertaking pre-planned work that is hazardous.

Policy A leagally required statement of an organisation’s strategy for achieving a safe and healthy working environment and the responsibility, organisation and arrangements for enacting it.

Prohibition Notice A statutory notice to stop an activity from starting or to cause it to cease. It can be issued by Health and Safety Executive (HSE), Environmental Health Officer (EHO) or Fire Officer.

Regulation Regulations are approved by parliament and are generally absolute legal standards.

Risk A quantifiable expression of the likelihood of injury or harm resulting from a hazard

Risk Assessment A formal estimation, legally required for every workplace, of the likelihood that persons may suffer injury or adverse health effects as a result of identified hazards

Risk Management The introduction of change or control measures with the intention of eliminating or bringing the level of risk associated with a hazard within acceptable limits

Safe System of Work A method of working designed to eliminate, if possible, or otherwise reduce risks to health and safety

Safety Committee A committee that promotes health and safety in the workplace, with members representing employees and management from all sections of an organisation. Standards are outlined in Safety Representatives & Safety Committee Regulations 1977

Safety Culture The degree to which the culture of an organisation promotes and co-operates with safe and healthy work practices

Stress When an event or situation places increased demand on mental or emotional resources beyond capacity leading to health and safety related problems such as depression, cardiovascular disease, and musculo-skeletal disorders.

Toxic Substances cause irritation or are otherwise harmful to health, such as carcinogens and poisons

Vocationally Related Qualification is a nationally recognised award or certificate that is related to work. There are a number of VRQs for health and safety.

Volatility Ability of a substance to evaporate

Workplace Exposure Limit (WEL) Concentration of a substance that, if not exceeded, will not normally result in significant adverse effects to persons who are exposedction level

exposure level at which (USA) OSHA regulations take effect. This is generally one-half of the PEL.

acute effectone which involves severe symptoms which develop rapidly and may quickly reach a crisis.

acute exposurea short-term exposure usually occurring at high concentration.

acute hazardone to which a single exposure may cause harm, but which is unlikely to lead to permanent damage.

acute health effectan effect that develops either immediately or a short time after exposure.

Allergic Contact Dermatitis

type of skin hypersensitivity. Its onset may be delayed by several days to as much as several years, for weaker sensitizers. Once sensitized, fresh exposure to the sensitizing material can trigger itching and dermatitis within a few hours.

Ames Test

used to assess whether a chemical might be a carcinogen. It assumes that carcinogens possess mutagenic activity, and uses bacteria and mammalian microsomes to determine whether a chemical is a mutagen. Approximately 85% of known carcinogens are mutagens. The Ames test, therefore, is a helpful but not perfect predictor of carcinogenic potential.

Argyria or Argyrism

an irreversible blueish-black discolouration of the skin, mucous membranes or internal organs caused by ingestion of, or contact with, various silver compounds.

auto-ignition temperature

(of a chemical ) - the lowest temperature at which the material will ignite without an external source of ignition.

breakthrough time

the time taken in standard tests for permeation of a chemical through a protective barrier (such as a rubber glove) to be detected.

boiling point

the temperature at which a liquid changes from a liquids to a gas, at normal atmospheric pressure.

carcinogen

chemical known or believed to cause cancer in humans. The number of known carcinogens is comparatively small, but many more chemicals are suspected to be carcinogenic.

CAS Registry number

a unique, identifying number assigned to a chemical by the Chemical Abstracts Service (CAS).

chemical formula

sometimes called the molecular formula, indicates the elements that make up a chemical.

chemical name

a proper scientific name for the active ingredient of a product.

chronic exposure

a long-term exposure, usually occurring at low concentrations.

chronic hazard

chemical which has the potential to cause long-term damage to health, often as a consequence of repeated or prolonged exposure to it.

chronic health effect

an effect that appears a long time after exposure.

Chrysiasis

development of a blue-grey pigmentation in skin and mucous membranes. May be caused by exposure to gold compounds.

coefficient of oil/water distribution

the ratio of the solubility of the chemical in an oil to its solubility in water. (see Partition Coefficient)

combustible liquid

a liquid which has a flash point above 37.8 C (100° F).

compressed gas

a material which is a gas at normal room temperature (20 C) and pressure but is packaged as a pressurized gas, dissolved gas or gas liquified by compression or refrigeration.

condensation

the process of reducing from one form to another denser form such as steam to water.

corrosive material

a material that can attack (corrode) metals or cause permanent damage to human tissues such as skin and eyes on contact.

COSHH

(Control of Substances Hazardous to Health) - COSHH regulations impose a number of obligations on employers; the object of the regulations is to promote safe working with potentially hazardous chemicals.

cryogenics

materials which exist at extremely low temperatures, such as liquid nitrogen.

cutaneous hazard

a chemical which may cause harm to the skin, such as defatting, irritation, skin rashes or dermatitis.

degradation

term generally used to describe the loss of resilience of material used for protective gloves. Degradation may cause the material to soften, swell, become hard and brittle, or - in severe cases - disintegrate.

density

the weight of a material in a given volume. It is usually given in grams per millilitre (g/ml).

dilution ventilation

dilution of contaminated air with uncontaminated air in a general area, room or building for the purposes of health hazard or nuisance control, and/or for heating and cooling.

dose

amount of the agent that has entered the body through the various routes of entry.

D.O.T.

Common abbreviation for the U.S. Department of Transportation, which regulates the transport of chemicals in the U.S.A.

DOT hazard codes

1	Explosives
2.1	Flammable gas
2.2	non-flammable gas
2.3	Poisonous gas
3	Flammable liquid
4.1	Flammable solid
4.2	Spontaneously combustible
4.3	Dangerous when wet
5.1	Oxidizer
5.2	Organic peroxide
6.1	Poison- keep away from food
6.2	Infectious material
7	Radioactive
8	Corrosive
9	Miscellaneous

ED50

(Effective Dose 50) - the amount of material required to produce a specified effect in 50% of an animal population. (See qualification in the definition of LD50).

EINECS

acronym for European Inventory of Existing Commercial Chemical Substances.

ELINCS

cronym for European List of Notified Chemical Substances.

embryotoxins

retard the growth or affect the development of the unborn child. In serious cases they can cause deformities or death. Mercury compounds and certain heavy metals, aflatoxin, formamide and radiation are known embryotoxins.

etiologic agents

microscopic organisms such as bacteria or viruses, which can cause disease.

evaporation rate

the rate at which a liquid changes to vapour at normal room temperature.

explosive (flammable) limits

the lower explosive (flammable) limit (LEL) is the lowest concentration of vapour in air which will burn or explode upon contact with a source of ignition. The upper explosive (flammable) limit (UEL) is the highest concentration of vapour in air which will burn or explode upon contact with a source of ignition.

explosive (flammable) range

the range between the lower explosive limit (LEL) and the upper explosive limit (UEL).

exposure limits

established concentrations which, if not exceeded, will not generally cause adverse effects to the worker exposed. Exposure limits differ in name and meaning depending on origin. For example:-

1. Permissible Exposure Levels are legally enfoceable exposure limits, set by OSHA.  PELs are not available for all chemicals.  Different exposure limits include:

TWA Time-Weighted Average: The average airborne concentration of a biological or chemical agent to which a worker may be exposed in a work day or a work week.

STEL Short Term Exposure Level: - The maximum airborne concentration of a chemical or biological agent to which a worker may be exposed in any 15 minute period, provided the TWAEV is not exceeded.

CEILING Ceiling Exposure Level: The maximum airborne concentration of a biological or chemical agent to which a worker may be exposed at any time.

SKIN: This notation indicates that direct or airborne contact with the product may result in significant absorption of the product through the skin, mucous membranes or eyes. Inclusion of this notation is intended to suggest that preventative action be taken against absorption of the agent through these routes of entry.

2. Threshold Limit Values (TLVs) are exposure guidelines developed by the American Conference of Governmental Industrial Hygienists (ACGIH). They are not legally enforceable, but because they are updated regularly, they represent good professional practice. They are expressed as follows:-

TLV-TWA Threshold Limit Value - Time-Weighted Average: The time-weighted average concentration for a normal 8 hour work day and a 40 hour work week, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect.

TLV-STEL Threshold Limit Value - Short Term Exposure Limit: a 15 minute time-weighted average exposure which should not be exceeded at any time during a work day even if the 8 hr TWA is within the TLV. Exposures at the STEL should not be repeated more than 4 times a day and there should be at least 60 minutes between successive exposures at the STEL.

TLV-C Threshold Limit Value - Ceiling: the concentration that should not be exceeded during any part of the working exposure.

Other exposure limits include the Permissible Exposure Limits (PEL) which are legal exposure limits in the United States.

f/cc

fibres per cubic centimetre of air.

FDA

U.S. Food and Drug Administration.

flammable limits

flashback

occurs when the flame in a gas torch burns back into the torch or hose; this is often accompanied by a hissing or squealing sound, and a pointed or smoky flame.

flash point of a chemical is the lowest temperature at which a flame will propagate through the vapour of a combustible material to the liquid surface. It is determined by the vapour pressure of the liquid, since only when a sufficiently high vapour concentration is reached, can it support combustion. It should be noted that the source of ignition need not be an open flame, but could equally be, for example, the surface of a hot plate, or a steam pipe.

freezing point

the temperature at which a liquid becomes a solid, at normal atmospheric pressure.

hazard

the potential for harmful effects.

hazard codes

see UN hazard codes.

hazardous decomposition products

formed when a material decomposes (breaks down) because it is unstable, or reacts with materials such as water or oxygen in air.

hazardous polymerization

Polymerization is a process of forming a polymer by combining large numbers of chemical units or monomers into long chains (polyethylene from ethylene or polystyrene from styrene). Uncontrolled polymerization can be extremely hazardous. Some polymerization processes can release considerable heat or can be explosive.

hematopoietic agent

chemical which interfers with the blood system by decreasing the oxygen-carrying ability of haemoglobin. This can lead to cyanosis and unconsiousness. Carbon monoxide is one such agent, familiar to smokers.

hepatotoxin

chemical capable of causing liver damage.

HSE

Health and Safety Executive. The HSE web site can be reached through http://www.hse.gov.uk/. The HSE is responsible for proposing and enforcing safety regulations throughout UK industry and academia. Publications are available on a wide variety of safety-related issues.

hypoxia

a condition defined by a low supply of oxygen.

inhibitor

material which is added to a chemical to prevent an unwanted reaction. For example, BHT (2,6-di-t-butyl-p-cresol) is often added to tetrahydrofuran to prevent potentially dangerous polymerisation.

ingestion

means taking a material into the body by mouth (swallowing).

inhalation

means taking a material into the body by breathing it in.

IARC

International Agency for Research in Cancer. 

IOSH

Institute for Occupational Safety and Health. 

irritant

chemical which may cause reversible inflammation on contact.

LC50 (Lethal Concentration 50)

the concentration of a chemical which kills 50% of a sample population. This measure is generally used when exposure to a chemical is through the animal breathing it in, while the LD50 is the measure generally used when exposure is by swallowing, through skin contact, or by injection. (See also LD50).

LD50 (Lethal Dose 50)

the dose of a chemical which kills 50% of a sample population. In full reporting, the dose, treatment and observation period should be given. Further, LD50, LC50, ED50 and similar figures are strictly only comparable when the age, sex and nutritional state of the animals is specified. Nevertheless, such values are widely reported and used as an effective measure of the potential toxicity of chemicals. (See also LC50).

LDLO

Lethal Dose Low

LEL (Lower Explosive Limit)

local exhaust ventilation

involves the capture of pollutants at the source.

median lethal dose (MDL)

 LD50.

MEL (Maximum Exposure Limit)

the maximum permitted concentration of a chemical to which a worker may be exposed over an extended period of time. Typically, MELs are quoted in ppm for an 8-hour reference period, though shorter periods may be quoted for some materials. MELs are, in many countries, enforceable by law. 

melting point

the temperature at which a solid material becomes a liquid.

MSDS

a widely used abbreviation for Material Safety Data Sheet, which contains details of the hazards associated with a chemical, and gives information on its safe use.

mutagen

an agent that changes the hereditary genetic material which is a part of every living cell. Such a mutation is probably an early step in the sequence of events that ultimately leads to the development of cancer.

NIOSH

(National Institute for Occupational Safety and Health)- sets OELs and provides services in occupational health and safety investigations in the USA. 

nephrotoxin

a chemical which may cause kidney damage. Common examples include antimony compounds, dimethyl sulphoxide, dimethylformamide and tetrahydrofuran.

neurotoxin

chemical whose primary action is on the CNS (Central Nervous System). Many neurotoxins, such as some mercury compounds, are highly toxic, and must only be used under carefully-controlled conditions.

nuisance material

is one which can cause transient irritation or discomfort, but which has no long-term or systemic effects.

OEL(Occupational Exposure Limit)

A (generally legally-enforcable) limit on the amount or concentration of a chemical to which workers may be exposed.

odour threshold

the lowest airborne concentration, usually in part per million, of a vapour in air which can be detected by smell.

OES

Occupational Exposure Standard

oxidizing material

gives up oxygen easily or can readily oxidize other materials.

partition coefficient

PEL (Permissible Exposure Limit)

a time-weighted average (TWA) or absolute value (usually prescribed by regulation) setting out the maximum permitted exposure to a hazardous chemical.

peroxidizable materials

can form peroxides in storage, generally when in contact with the air. These peroxides present their most serious risk when the peroxide-contaminated material is heated or distilled, but they may also be sensitive to mechanical shock. The quantity of peroxides in a sample may be determined using a simple peroxide test strip.

pH

a measure of the acidity or basicity (alkalinity) of a material when dissolved in water.

Photoallergic Contact Dermatitis a skin condition brought on by exposure to light following skin contact with certain types of chemicals, such as sulphonamides.

Pictographs

widely-used pictorial representations of the hazards presented by chemicals.

Poison Class A or B

classified by the DOT into two classes. Those in Class A are highly toxic materials which, even in very small quantities, present a hazard to life. Examples of such gases are cyanogen, phosgene and hydrocyanic acid. Class B poisons, though less toxic, are presumed to present a serious threat to health during transportation.

polymer

a natural or man-made material formed by combining units, called monomers, into long chains.

polymerization

a process of forming a polymer by combining large numbers of chemical units or monomers into long chains.

PPB (Parts Per Billion)

used to specify the concentration (by volume) of a gas or vapour at very low concentration, or a dissolved material at high dilution.

PPM (Parts Per Million)

used to specify the concentration (by volume) of a gas or vapour at low concentration, or a dissolved material at high dilution.

pyrophoric materials

ignite spontaneously in air. Since a wide variety of chemicals will burn if heated sufficiently, it is usual to define a pyrophoric material as one which will ignite spontaneously at temperatures below about 45 C.

reactive materials

materials that may undergo vigorous condensation, decomposition or polymerization. They may react violently under conditions of shock or increase in pressure or temperature. They may also react vigorously with water or water vapour to release a toxic gas.

reproductive toxin

(such as vinyl chloride or PCBs) - a chemical which may cause birth defects or sterility.

risk phrases

coded in the form R34, R61 etc are now included in MSDS sheets for chemicals purchased in the UK. A list of the meaning of these codes is available at

sensitization

the development, over time, of an allergic reaction to a chemical.

sensitizer

a chemical which may lead to the development of allergic reactions after repeated exposure.

solubility

the ability of a material to dissolve in water or another liquid.

solvent

a material which is capable of dissolving another chemical.

specific gravity

the density of a liquid compared to the density of an equal amount of water.

stability

the ability of a material to remain unchanged in the presence of heat, moisture or air.

STEL (Short Term Exposure Limit)

the maximum permissible concentration of a material, generally expressed in ppm in air, for a defined short period of time (typically 5 minutes). These values, which may differ from country to country, are often backed up by regulation and therefore may be legally enforceable.

systemic poisons

have an effect which is remote from the site of entry into the body.

TD50

TD50 may be defined as follows: for a given target site(s), if there are no tumors in control animals, then TD50 is that chronic dose-rate in mg/kg body wt/day which would induce tumors in half the test animals at the end of a standard lifespan for the species. Since the tumor(s) of interest often does occur in control animals, TD50 is more precisely defined as: that dose-rate in mg/kg body wt/day which, if administered chronically for the standard lifespan of the species, will halve the probability of remaining tumorless throughout that period. A TD50 can be computed for any particular type of neoplasm, for any particular tissue, or for any combination of these. The range of statistically significant TD50 values for chemicals in the CPDB that are carcinogenic in rodents is more than 10 million-fold.

teratogen

chemical which may cause genetic mutations or malformations in the developing fetus. Agents or compounds that a pregnant woman takes into her body that generate defects in the fetus.

TLV (Threshold Limit Value)

the maximum permissible concentration of a material, generally expressed in parts per million in air for some defined period of time (often 8 hours). These values, which may differ from country to country, are often backed up by regulation and therefore may be legally enforceable. See "Exposure Limits".

TLV-C (ceiling exposure limit)

an exposure limit which should not be exceeded under any circumstances.

toxicity

ability of a substance to cause harmful effects.

trade name

the name under which a product is commercially known.

TSCA (Toxic Substances Control Act)

regulates the manufacture, transport and use of toxic substances in the USA.

TWA (Time Weighted Average)

term used in the specification of Occupational Exposure Limits (OELs) to define the average concentration of a chemical to which it is permissible to expose a worker over a period of time, typically 8 hours. See "Exposure Limits"

UEL (Upper Explosive Limits)

See "Explosive Limits".

UN Hazard codes

Class 1	Explosive
Class 2	Gases
Class 3.1	Flammable liquids, flash point below -18C
Class 3.2	Flammable liquids, flash point between -18C and 23C
Class 3.3	Flammable liquids, flash point between 23C and 61C
Class 4.1	Flammable solids
Class 5.1	Oxidizing agents
Class 5.2	Organic peroxides
Class 6.1	Poisonous substances
Class 7	Radioactive substances
Class 8	Corrosive substances
Class 9	Miscellaneous dangerous substances
NR	Non-regulated

UN Number

a four digit number assigned to a potentially hazardous material or class of materials. UN (United Nations) numbers are internationally recognized and are used by fire fighter and other emergency response personnel for identification of materials during transportation emergencies. NA (North American) numbers are assigned by Transport Canada and the US Department of Transport to materials they consider hazardous and to which a UN number has not been assigned.

vapor

a gaseous form of a material which is normally solid or liquid at room temperature and pressure.

vapour density

the density of a vapour compared to the density of an equal amount of air.

vapour pressure

the pressure of a vapour in equilibrium with its liquid or solid form.

ventilation

the movement of air.

vesicant

a chemical which, if it can escape from the vein, causes extensive tissue damage, with vesicle formation or blistering.

VOCs

Volatile Organic Compounds.

volatility

the ability of a material to evaporate.

Backing fire: Fire that is moving into the wind (See heading and flanking fire).

Backfiring:  Intentionally setting fire to fuels inside a control line to contain a fire.  

Blackline:  Refers to fuels that have burned, either intentionally or not.  Many prescribed fire and wildfire suppression techniques are based on the concept of blackline as a barrier to fire spread.

Catface: General term used to describe the triangular wound found at the base of a tree and often caused by fire. From one to many fire scar lesions caused by individual fire events can be found within the catface.

Chain: A traditional forestry term equal to 66' or approximately 20 m.

Conduction: The movement of heat from one molecule to another.

Convection: The movement heat by currents in liquids or gases.

Creeping fire:  A low intensity fire with a negligible rate of spread.

Crown Fire: Fire that has ascended from the ground into the forest canopy.

Drip Torch:  An ignition tool which drips a mixture flaming diesel and gasoline onto the ground.

ire Behavior:The manner in which a fire reacts to fuel, weather, and topography. Common terms used to describe behavior include: smoldering, creeping, running, spotting, torching, and crowning.

Fire Cycle:

1) A fire-return interval calculated using a negative exponential (or Weibull) distribution, applied using current age-class structure on the landcape.
2) Length of time required to burn an area equal in size to a specified area.

Fire Event: A single fire or series of fires within an area at a particular time.

Fire-Free Interval: Time between two successive fire events at a given site or an area of a specified size.

Fire Frequency: The return interval or recurrence interval of fire in a given area over a specific time.

Fire Intensity Energy release per unit length of flame front.

Fire Predictability: A measure of variation in fire frequency expressed as a range, standard deviation, or standard error.

Fire Regime: The combination of fire frequency, predictability, intensity, seasonality, and size characteristics of fire in a particular ecosystem.

Fire-Return Interval: The number of years between two successive fire events at a specific site or an area of a specified size.

Fire Rotation: The length of time necessary to burn an area the size of a specific area (for example a watershed).

Fire Severity: The effect of fire on plants. It is dependant on intensity and residence dependant of the burn. An intense fire may not necessarily be severe. For trees, severity is often measured as percentage of basal area removed.

Fireline Intensity: The rate of heat release along a unit length of fireline, measured in kW m-1.

lame Length: The average length of the flame front from the ground to the flame tips.

Flanking Fire: Fire that is moving perpendicular to the wind (See heading and backing fire).

Foehn Wind: A dry wind associated with windflow down the lee side of a plateau or mountain range and with adiabatic warming (also called Santa Ana [southern California], Mono or North Wind [N. and central California], East Wind [western Washington and Oregon] or Chinooks [east side of Rockies] in other regions).

Fuel:

Description	Material	Diameter
Fine	Needles, leaves, etc...
1 Hour	Woody material, generally drying out within 1 hour.	<1/4"
10 Hour	Woody material, generally drying out within 10 hours.	1/4"-1"
100 Hour	Woody material, generally drying out within  4 days.	1-3"
1000 Hour	Woody material, generally drying out within 40 days.	3"+
Downed	Fuel on the ground
Heavy	Large logs and snags

Fuel Load: The amount of available and potentially combustible material, usually expressed as tons/acre.

Fuel Model:  A standardized description of fuels available to a fire based on the amount, distribution and continuity of vegetation and wood.

Fuel Moisture: The amount of water in a fuel sample.  The proportion of water to dry material. Percent fuel moisture = (Wet weight - Dry weight)/Dry weight * 100.  Fire behavior is dependent, to a large extent, on how much water is in the fuel.

Ground Fire (or surface fire):-- Fire burning on the ground or through the understory and not reaching into the canopy.

Heading Fire: Fire that is moving with the wind (See backing and flanking fire).

Ladder Fuels:  Fuels, such as branches, shrubs or an understory layer of trees, which allow a fire to spread from the ground to the canopy. 

Mass Transfer: The movement of heat by burning firebrands, as used in the fire literature.

Master Fire Chronology: A chronology of all documented fire dates in designated area determined by crossdating.

Mean Fire-Return Interval (or mean fire-free interval, or mean fire interval: Arithmetic average of all fire-return intervals for a specific site for a specific interval of time.

Prescribed Fire: (also called prescribed or controlled burn) A fire ignited under known conditions of fuel, weather, and topography to achieve specific objectives.

Prescription A statement or plan specifying management objectives to be obtained, and air temperature, humidity, season, wind direction and speed, fuel and soil moisture conditions under which a fire will be started or allowed to burn.

Relative Humidity:  The ratio of water vapor in the air to the maximum amount of vapor the air can hold at a given temperature and pressure.  Fire behavior is dependent on, and can be predicted from, relative humidity. 

Rate of Spread:  The speed a fire travels, generally expressed as chains/hour.

Spot Fire:  A smaller fire that has started from sparks and brands thrown in the air by the main fire.

Spotting: Mass transfer of firebrands ahead of a fire front.

Surface Fire: A fire burning along the surface without significant movement into the understory or overstory, with flame length usually below 1 m.

Timelag Class: A method of categorizing fuels by the rate at which they are capable of moisture gain or loss, indexed by size class (see fuel definition).

Torching Fire: Fire burning principally as a surface fire that intermittently ignites the crowns of trees or shrubs as it advances.

Understory Fire: A fire burning in the understory, more intense than a surface fire with flame lengths of 1-3 m.

dardized description of the vegetation in which a fire is burning.  The type is based on the dominant plant species and the age of the forest and indicates how moist a site may be and how much fuel is likely to be present.

Water Repellency: The resistance to soil wettability, which can be increased by intense fires.

WFRB:  Wild Fire for Resource Benefit.

Wildfire: A fire, naturally caused or caused by humans, that is not meeting land management objectives.

Wildland-Urban Interface: Zone where structures and other human developments meet, or intermingle with, undeveloped wildlands.

Absorption:
1) A mechanical phenomenon wherein one substance penetrates into the inner structure of another, as in absorbent cotton or a sponge.
2) An optical phenomenon wherein atoms or molecules block or attenuate the transmission of a beam of electromagnetic radiation. Accelerant: Any material used to initiate or promote the spread of a fire. The most common accelerants are flammable or combustible liquids. Whether a substance is an accelerant depends not on its chemical structure, but on its use. Acetone: The simplest ketone. A highly flammable, water soluble solvent. Flash point of 0°F. Explosive limits of 2.6% to 12.8%. Adsorption: The adherence of atoms, ions or molecules of a gas or liquid to the surface of another substance. Finely divided or microporous materials having a large active surface area are strong adsorbents. Examples include activated carbon, activated alumina and silica gel. Alcohol: An organic compound having a hydroxyl (-OH) group attached. The lower molecular weight alcohols, methanol (CH3OH), ethanol (C2H5OH), and propanol (C3H7OH) are water soluble. Aliphatic: One of the main groups of hydrocarbons characterised by the straight or branched chain arrangement of constituent atoms. Aliphatic hydrocarbons belong to three subgroups:

1. alkanes or paraffins, all of which are saturated and comparatively unreactive,
2. the alkenes or alkadienes which are unsaturated (containing double [C=C] bonds) and more reactive, and
3. alkynes, such as acetylene (which contain a triple [C=C] bond).

Alkane: An aliphatic hydrocarbon having the chemical formula CnH2n+2 A normal alkane, or n-alkane is one which does not have a branched carbon backbone. An iso-alkane has a branched, rather than a straight chain, carbon backbone. Alkanes are also known as paraffins. The simplest alkanes are named as follows:

• CH4 methane
• C6H14 hexane
• C2H6 ethane
• C7H16 heptane
• C3H8 propane
• C8H18 octane
• C4H10 butane
• C9H20 nonane
• C5H12 pentane
• C10H22 decane

Alkene: A straight chain, unsaturated compound of the olefin series which has the generic formula ..., having at least one double [C=C] bond. Alkyl Group: A functional group having the formula ... which may be attached to certain elements such as lead, silicon, or to other organic chemicals. Alkyne: An unsaturated aliphatic hydrocarbon characterised by the presence of a triple [C=C] bond. The generic formula for an alkyne is .... The most important member of this group is acetylene, HCCH, the first member of the series Alloy: A solid or liquid mixture of two or more metals, or of one or more metals with certain nonmetallic elements, as in brass, bronze or carbon steel. Ambient: Pre-existing or normal environment. Aromatic: An organic compound having as part of its structure a benzene ring. The term 'aromatic' as used in the fragrance industry is used to describe essential oils, which are not necessarily aromatic in the chemical sense. Arson: The crime of intentionally setting fire to a building or other property. This is a legal definition which may vary depending on the laws of a specific state. Atom: The smallest unit of en element which still retains the chemical characteristics of that element. An atom is made up of protons and neutrons in a nucleud surrounded by electrons. A molecule of water (H20) consists of two atoms of hydrogen and one atom of oxygen. Atomic Absorption: An analytical technique, used to determine the elemental composition and concentration of many metals and other inorganic elements. The material being analysed, generally in solution, is atomised, or broken up into individual atoms, usually by the action of extreme heat in a flame or small furnace. The ability of the atomised material to absorb characteristic wavelengths of visible or ultraviolet light is then measured using a spectrophotometer. Atomise:
1) To break down into discrete atoms, usually by the application of extreme heat, as in atomic absorption,
2) To break a liquid into tiny droplets, as occurs in fuel injected engines or in the production of aerosol sprays. Attenuation: An adjustment of the signal amplifier response which results in the reduction of the electronic signal. Azeotrope: A mixture of two or more compounds which has a constant boiling point. The composition of the vapour above the azeotropic mixture has the same relative concentrations of compounds as does the boiling liquid. Azeotropic mixtures cannot be separated by fractional distillation. Benzene: A hexagonal organic molecule having a carbon atom at each point of the hexagon and a hydrogen atom attached to each carbon atom. Molecules which contain a benzene ring are known as aromatic. Benzene boils at 80°C and has a flash point of 12°F (-11°C). The explosive limits are 1.5% to 8% by volume in air. BTU: British Thermal Unit. The amount of heat energy required to raise the temperature of one pound of water one degree Fahrenheit. This is the accepted standard for the comparison of heating values of different fuels. One BTU equals 252 calories. Burning: Normal combustion in which the oxident is molecular oxygen. Burning Rate: The rate at which combustion proceeds across a fuel. A specialised use of this term, describes the rate at which the surface of a pool or burning liquid recedes. For gasoline, this rate is reported to be approximately ¼ inch per minute. Butane: A fuel gas having the formula C4H10. A constituent of LP gas. One pound of liquid butane produces 6.4 cubic feet of gas. One gallon of liquid butane weighs 4.87 pounds and produces 31 cubic feet of gas. One cubic foot of butane gas produces 3266 BTUs. Calorie: The amount of energy required to raise the temperature of one gram of water one degree Centigrade. One calorie equals 0.004 BTUs. One BTU equals 252 calories. Capillary: A narrow bore glass tube. Capillary column gas chromatography employs glass tubes having an inside diameter of approximately .2 to .5 millimetres and a length of 3 to 300 metres. The walls of a capillary column are coated with an adsorbent medium (a liquid phase in which the sample dissolves). Carbon: The element upon which all organic molecules are based. Carbon has an atomic weight of 12.00, and occurs elementally in these forms: diamond, graphite and amorphous carbon such as coal or carbon black. Carbon Dioxide: A molecule consisting of one atom of carbon and two atoms of oxygen which is a major combustion product of the burning of organic materials. Carbon Dioxide (CO2) is the result of complete combustion of carbon. In the gaseous form, CO2 is used as a fire extinguisher. In the solid form, CO2 is known as dry ice. CO2 is heavier than air, with a vapour density if 1.53 (air = 1.00). Carbon Disulfide: A highly flammable nonpetroleum solvent used for gas chromatography because of its relatively low signal generated in a flame ionisation detector. Carbon disulfide has the formula CS2. Reagent grade CS2 has an odour similar to rotten broccoli and can be ignited by contact with boiling water. It burns with a blue flame, providing CO2 and SO2 (sulfur dioxide). The explosive limits of CS2 are 1 to 50%. CS2 has a flash point of -22°F. Carbon Monoxide: A gaseous molecule having the formula CO, which is the product of incomplete combustion of organic materials. Carbon monoxide has an affinity for haemoglobin approximately 200 times stronger than oxygens and is highly poisonous. CO is a flammable gas which burns with a blue flame and has explosive limits of 12% to 75%. Carbon monoxide has approximately the same vapour density as air, 0.97 air (air = 100). Carbon Tetrachloride: A nonflammable liquid having the formula CC14, formerly used as a fire extinguisher, and still used as a solvent and cleaning agent. Carbon tetrachloride boils at 77°C. Chain Reaction: A self-propagating chemical reaction in which activation of one molecule leads successfully to activation of many others. Most, perhaps all, combustion reactions are of this kind. Chemical Change: Rearrangement of the atoms, ions or radicals or one or more substances, resulting in the formation of new substances, often having entirely different properties. Also known as a chemical reaction. Chemistry: A basic science concerned with

1. the structure and behaviour of atoms (elements);
2. the composition and properties of compounds;
3. the reactions that occur between substances and the resultant energy exchange and
4. the laws that unite these phenomena into a comprehensive system.

Chromatogram: A series of peaks and valleys printed or written on a paper chart where each peak represents a component or mixture of two or more unresolved components in a mixture separated by gas or liquid chromatography. Chromatography: A chemical separation procedure which separates compounds according to their affinity for an adsorbent or absorbent material. Chromatography includes Thin Layer Chromatography (TLC), Liquid Chromatography (LC), Gas Chromatography (GC), (sometimes called Gas Liquid Chromatography or GLC) and High Performance Liquid Chromatography (HPLC). Comparison Sample:
1) A sample of material collected from a fire scene which is, to the best of the investigators knowledge, identical in every respect to a sample suspected of containing accelerant, but which does not contain accelerant.
2) A sample of suspected accelerant submitted for the purpose of comparing with any accelerant separated from a debris sample. Combustible Liquid: A liquid which is capable of forming a flammable vapour/air mixture. All flammable liquids are combustible. Whether a liquid is flammable or combustible depends on its flash point and on the agency definition relied upon. The Coast Guard classifies all liquid having a flash point over 80°F as combustible and liquids with a flash point below 80°F as flammable. The NFPA uses 100°F. Combustion: An exothermic chain reaction between oxidising and reducing agents, or between oxygen and fuel. combustion may occur with any organic compound, or with certain combustible elements such as hydrogen, sulfur and finely divided metals. Component: 1) One of the elements or compounds present in a system such as a phase, a mixture, a solution or a suspension in which it may or may not be uniformly dispersed.
2) A compound or a group of unresolved compounds represented by a peak on a chromatogram. Compound: A chemical combination of two or more elements, or two or more different atoms arranged in the same proportions and in the same structure throughout the substance. A compound is different from a mixture in that the components of a mixture are not chemically bonded together. For example, a flask may contain two volumes of hydrogen (H2) gas and one volume of oxygen gas (O2). A different glass might contain only water vapour (H20). In the first case, two gases are mixed. In the second case, only one gas is present. Concentration: the amount of a substance in a stated unit of a mixture or solution. Common methods of stating concentration are per cent by weight, per cent by volume, or weight per unit volume (eg: parts per million, billion, etc.). Conduction: Passage of heat from one material to another by direct contact. Conductivity: The ability of a material to transfer energy from one place to another. Thermal conductivity describes a substances ability to transmit heat. Electrical conductivity describes a substances ability to transmit electrical current. Conductivity is to the opposite if resistivity. Control Sample: A sample of material which is known to be identical to a sample suspected of containing accelerant in every regard, except that the control sample does not contain accelerant. A known blank sample. In practical terms, control samples do not exist in the setting of a fire scene because
(1) exact conditions during the fire cannot be duplicated from location to location, and
(2) exact conditions of the substrate, ie: carpet, etc., are not known. Carpet in Room A may have had various items spilled on it during use. Carpet B (ten feet away) may be brand new. Convection: Transfer of heat by the movement of molecules in a gas or liquid with the less dense fluid rising. The majority of heat transfer in a fire is by convection. Corrosion: The degradation of metals or alloys due to reaction with their environment. It is accelerated by acids, bases or heats. Cracking: A refining process involving decomposition and molecular recombination of organic compounds, especially hydrocarbons obtained by distillation of petroleum, by means of heat, to form molecules suitable for various uses such as motor fuels, solvent or plastics. Cracking takes place in the absence of oxygen. Deflagration: Vigorous burning with subsonic flame propagation.. Desorption: the process of removing an adsorbed material from the solid on which it is adsorbed. Detonation: An exothermic chemical reaction which propagates through reactive material at supersonic speed. Diesel Fuel: Diesel Fuel consists mostly of hydrocarbons ranging from C10 to C24. The composition of diesel fuel may vary with changes in latitude or changes in season. this variability is provided by the refinery to control the volatility of the product. In order to be identified as diesel fuel, a sample extract must exhibit a homologous series of five or more consecutive normal alkanes ranging from C12 through C22. Diesel fuel has a flash point of 120 to 160°F and explosive limits of 0.7% to 5%. Many states specify a minimum flash point for diesel fuel. Distillation: A separation process in which a liquid is concerted to a vapour and the vapour is then condensed back to a liquid. The usual purpose of distillation is separation of the compounds of a mixture. Steam distillation separates all water insoluble liquids from solids and water soluble compounds in a mixture. Drying Oil: An organic liquid which, when applied as a thin film, readily absorbs oxygen from the air and polymerises to form a tough elastic film. Linseed, tung, soybean and castor oils are drying oils. Under certain conditions, usually involving large surface areas and insulation, such as a pile of rags soaked with drying oils, spontaneous heating may occur. Electron: A negatively charged subatomic particle which circles the nucleus of the atom in a cloud. Most chemical reactions involve the making and breaking of bonds held together by the sharing of electrons. Electron Capture Detector (ECD): A type of gas chromatographic detector which is sensitive to halogenated hydrocarbons and other molecules capable of easily gaining an electron. Electron capture is not generally used for hydrocarbon detection. Element: One of 106 presently known kinds of substances that comprise all matter at and above the atomic level. Elution: the process of removing absorbed materials from the surface of an adsorbent such as activated charcoal. the solvent in this process is called the eluant. Emission Spectroscopy: The study of the composition of substances and identification of elements by observation of the wavelengths of radiation emitted by the substance as it returns to a normal state after excitation by an external source. Generally used for elemental analysis. Emulsion: A stable mixture of two or more immiscible liquids in suspension. Endothermic Reaction: A chemical reaction which absorbs heat. Ethane: A simple alkane having the formula C2H6. A minor component of natural gas. Its explosive range is 3% to 12.5%. Ethane has approximately the same vapour density as air. Ethanol: Ethyl alcohol. Grain alcohol. Flammable, water soluble alcohol. Flash point of 55°F. Explosive limits of 3.3% to 19%. Ether: Diethyl ether, ethyl ether. A highly flammable solvent which can form explosive peroxides when exposed to air. Flash point of -49°F. Explosive range of 1.85% to 48%. Ethylbenzene: A component of gasoline, but also a major breakdown product or pyrolsis product given off when certain polymers are heated. Eutetic: the lowest melting point of an alloy or solution of two or more substances (usually metals) that is obtainable by varying the percentage of the components. Eutetic melting sometimes occurs when molten aluminium or molten zinc comes in contact with solid steel or copper. Evaporation: Conversion of a liquid to the vapour state. See also vaporisation. Evaporation Rate: A measure of the quantity of a liquid converted to vapour in a unit of time. Among single component liquids, the rate varies directly with the surface area, the temperature and the vapour pressure, and inversely with the latent heat of vaporisation of the liquid. Exothermic Reaction: A chemical reaction which evolves heat. Combustion reactions are exothermic. Explosion: The sudden conversion of chemical energy into kinetic energy with the release of heat, light and mechanical shock. Explosive Limit: Flammability limit. The highest or lowest concentration of a flammable gas or vapour in air that will explode or burn readily when ignited. The limit is usually expressed as a volume percent of gas or vapour in air. Explosive Range: Flammability range. The set of all concentrations between the upper and lower explosive limits of a particular gas or vapour. Extraction: A chemical procedure for removing one type of material from another. Extraction is generally carried out by immersing a solid in a liquid, or by shaking two immiscible liquids together, resulting in the transfer of a dissolved substance from one liquid to another. Solvent extraction is one of the primary methods of sample preparation in arson debris analysis. Fire: The light and heat manifested by the rapid oxidation of combustible materials. A flame may be manifested but is not required. Fire Point: The temperature, generally a few degrees above the flash point, at which burning is self-sustaining after removal of an ignition source. Fire Tetrahedron: Fuel, heat, oxygen and a chemical chain reaction. Fire Triangle: Fuel, heat and oxygen. Flame: A rapid gas phase combustion process characterised by self-propagation. Flame Ionisation Detector (FID): A nearly universal gas chromatographic detector. It responds to almost all organic compounds. An FID does not respond to nitrogen, hydrogen, helium, oxygen, carbon monoxide or water. This detector ionises compounds as they reach the end of the chromatographic column by burning them in an air/hydrogen flame. As the compounds pass through the flame, the conductivity of the flame changes, generating a signal. The is the most commonly used detector in arson debris analysis. Flame Propagation: Travel of a flame through a combustible gas/air or vapour/air mixture. Flammability Limit:  Flammability Range:  Flammable Liquid: A combustible liquid that has a flash point below 80°F according to the Coast Guard, 100°F according to the NFPA. Liquids having a vapour pressure over 40 pounds per square inch at 100°F are classified as flammable gases. Flammable liquids are a special group of combustible liquids. Flammable Vapour: A vapour/air mixture of any concentration within the flammability range of that vapour. Flash Fire: A fire that spreads with unusual speed, as one that races over flammable liquid of through combustible gases. Flash Point: The temperature at which a pool of liquid will generate sufficient vapours to form an ignitable vapour/air mixture. The temperature at which a liquid will produce its lower explosive limit in air. Flash point describes one of several specific laboratory tests. Frequently materials can be made to burn below their flash point if increased surface area or mechanical activity raise the concentration of vapour in air above the lower explosive limit. Fractionation: The separation of one group of compounds in a mixture from another, generally by distillation. Fuel Oil: A heavy petroleum distillate ranging from #1 (kerosene or range oil), #2 (diesel fuel), up through #6 (heavy bunker fuels). To be identified as fuel oil, a sample must exhibit a homologous series of normal alkanes ranging from C9 upward. Gas Chromatography (also known as Gas Liquid Chromatography): The separation of organic liquids or gases into discrete components or compounds seen as peaks on a chromatogram. Separation us done in a column which is enclosed in an oven held at a specific temperature, or programmed to change temperature at a reproducible rate. The column separates the compounds according to their affinity for the material inside the column (stationary phase). Columns can be either packed or capillary. Packed columns employ a powdery substance which may be coated with a nonvolatile liquid phase. A capillary column is a glass or quartz tube coated with a nonvolatile liquid. Gas Chromatography (GC) is the accepted method for identification of hydrocarbon mixtures normally used as accelerants, and must be performed in order to have a valid identification of petroleum distillates. Gasoline: A mixture more than 200 volatile hydrocarbons in the range of C4 to C12 , suitable for use in spark ignited internal combustion engine. Regular automotive gasoline has a flash point of -40°F. Headspace Concentration: A technique for concentrating all or most of the flammable or combustible liquid vapours in a sample onto a tube of charcoal, a wire coated with charcoal, a charcoal coated polymer, or some other adsorbing material which will later be desorbed in order to analyse the concentrated vapours. This is a primary form of sample preparation in arson debris analysis. This is also known as adsorption/elution, vapour concentration, or total headspace. Heat: A mode of energy associated with and proportional to molecular motion that may be transferred from one body to another by conduction, convection or radiation. Heptane: An alkane having the formula C7H16, flash point of 25°F and explosive limits of 1.2% to 6.7%. Hexane: An alkane having the formula C6H14. Flash point -9°F. Explosive limits of 1.2% to 7.5%. Homologous Series: A series of similar organic compounds, differing only in that the next higher member of the series has an additional CH2 group (one carbon atom and two hydrogen atoms) in its molecular structure. Fuel oils are characterised by the presence of an identifiable homologous series of normal alkanes. Hydrocarbon: A organic compound containing only carbon and hydrogen. Hydrogen: The simplest element. Atomic Number 1. Hydrogen gas has a specific gravity of 0.0694 (air = 1), so it is much lighter than air. Hydrogen is highly flammable, forming water upon combustion. Explosive limits are 4% to 75%. Ignition: The means by which burning is started. Ignition Temperature: The minimum temperature to which a fuel must be heated in order to initiate of cause self sustained combustion independent of another heat source. Immiscible: Describes substances of the same phase or state of matter (usually liquids) that cannot be uniformly mixed or blended. Incendiaries: Substances or mixtures of substances consisting of a fuel and an oxidiser used to initiate a fire. Incendiary Fires: Fire set by human hands. Incidental Accelerants: Flammable or combustible liquids which are usual and incidental to an area where they are detected. Gasoline is incidental to an area where gasoline powered appliances are kept. Kerosene is incidental to an area where a kerosene heater is kept. Flammable liquids may also comprise a part of a product such as insecticide, furniture polish, or paint. Additionally certain ------ containing building materials may yield ------ of fuel oil components. Infrared Spectrophotometry (IR): An analytical technique which utilises an instrument which passes infrared radiation through a sample or which bounces infrared radiation off the surface of a sample. A very sensitive heat detecting device measures the amount of infrared radiation absorbed as the wavelength of the radiation reaching the detector is changed. IR can give useful information about the type of compounds present in a sample, but it is not capable of precisely identifying a complex mixture. Infrared is very useful in identifying single solvent accelerants. Intumescent Char: In plastics, the swelling and charring which results in a higher ignition point. Used in the preparation of flame retardant materials. Ion: An atom, molecule or radical that has lost or gained one or more electrons, thus acquiring an electric charge. Positively charged ions are cations; negatively charged ions are anions. Isomer: One of two or more forms a chemical compound which have the same number and type of each atom but a different arrangement of atoms. Isoparaffins: A mixture of branched alkanes usually available as a narrow 'cut' of a distillation. Exxon manufactures a group of products known as 'Isopars' ranging from Isopar A through Isopar J. These solvent mixtures have a variety of uses. Gulf Oil manufactures a similar series of solvents, the most commonly available of which is Gulf Life Charcoal Starter Fluid which is roughly equivalent to Exxon's Isopar G. Isothermal: A type of gas chromatographic analysis wherein the column is maintained at a uniform temperature throughout the analysis... Kerosene (#1 Fuel Oil): Flash point generally between 100 and 150 degrees F. Explosive limits of 0.7% to 5.0%. Kerosene consists mostly of C9 through C17 hydrocarbons. In order to be identified as kerosene, a sample extract must exhibit a homologous series five consecutive normal alkanes between C9 and C17. Kerosene is the most common 'incidental' accelerant, as it is used in numerous household products ranging from charcoal lighter fluid to lamp oil to paint thinner to insecticide carriers. It is also used as jet fuel. K-1 kerosene has a low sulfur content required for use in portable space heaters. Ketone: A type of organic compound having a carbonyl functional group (C=O) attached to two alkyl groups. Acetone is the simplest example of a ketone. Magnesium: A silvery metal used in some metal incendiaries. The dust is highly explosive. Ignition point of 650°F. Mass Spectrometry: A method of chemical analysis which vaporises, then ionises the substance to be analysed and then accelerates the ions through a magnetic field to separate the ions by molecular weight. Mass spectrometry can result in the exact identification of an unknown compound, and is a very powerful analytical technique, especially when combined with chromatography. Meta-ethylitoluene (m-ethyltoluene): A component of gasoline. Matrix: Substrate. the material from which a substance of interest is removed for analysis. Methane: The simplest hydrocarbon and the first member of the paraffin (alkane) series, having a formula CH4. Methane is the major constituent of natural gas. Methane has a heating value of 1009 BTU/cubic foot. Its explosive limits are 5% to 15%. Methanol: Methyl alcohol. Wood alcohol. The simplest alcohol. Methanol is water soluble and has a flash point of 54°F and explosive limits of 6% to 36.5%. Methyl Silicone: A nonvolatile oily liquid used in gas chromatography to separate nonpolar compounds. Methyl silicone columns typically separate compounds according to their boiling point. Methylstyrene: A common polymer pyrolysis product. Mineral Spirits: A medium petroleum distillate ranging from C8 to C12. The flash point of mineral spirits is generally around 100°F. Mineral spirits, sometimes known as mineral turps, is commonly known as a solvent in insecticides and certain other household products. Many charcoal lighter fluids are composed almost entirely of mineral spirits. Molecular Weight: The sum of the atomic weight of all of the atoms within a molecule. Generally, molecules of the same type have higher boiling points if the molecular weight is higher. Molecule: The smallest particle into which a substance can be divided without changing its chemical properties. A molecule of an element consists of one atom, or two or more atoms that are alike. A molecule of a compound consists of two of more different atoms. Monomer: The simplest unit of a polymer. Ethylene is the smallest unit of polyethylene. Styrene is the smallest unit of polystyrene. Naphtha: Am ambiguous term which may mean high flash naphtha (mineral spirits), or low flash naphtha (petroleum, ether, low boiling ligroin) or something altogether different. Flash point and explosive limits vary. The term naphtha is so ambiguous that it should not be used. Natural Gas: A mixture of low-molecular weight hydrocarbons obtained in petroleum bearing regions throughout the world. Natural gas consists of approximately 85% methane, 10% ethane and the balance propanes, butanes and nitrogen. since it is nearly odourless, an odorising agent is added to most natural gas prior to final sale. Nebulize: To form a mist of fine droplets from a liquid. To atomise. Nitrogen: A gaseous element which makes up approximately 80% of the earths atmosphere. Nitrogen is relatively inert and does not support either combustion or life. Nitrogen is usually found in the molecular N2 form. Octane:
(1) An alkane having the formula C8H18. Flash point 56°F. Explosive limits of 1% to 3.2%.
(2) A measure of the resistance of a sample of gasoline to premature ignition (knocking). 100 octane fuel has the knocking resistance of 100% iso-octane (2, 2, 4-trimethyl pentane). Zero octane fuel has the knocking resistance of a mixture of 89% iso-octane and 11% n-heptane. Olefin: An alkene. An organic compound similar to an alkane, but containing at least one double bond. Olefins have the formula CnH2n. The simplest olefin is ethylene, C2H4. Organic Chemistry: the study of the carbon atom and the compounds it forms, mainly with the 20 lightest elements, especially hydrogen, oxygen and nitrogen. Some 3 million organic compounds have been identified and named. Oxidation: Originally, oxidation meant a chemical reaction in which oxygen combines with another substance. The usage of the word has been broadened to include any reaction in which electrons are transferred. The substance which gains electrons is the oxidising agent. Oxygen: A gaseous element which makes up approximately 20% of the earths atmosphere. It is usually found in the molecular ... form. Oxygen is the most abundant element on earth. Pentane: An alkane having the formula C5H12, flash point of -40°F, and explosive limits of 1.4% to 8%. Pentane is frequently used to extract flammable or combustible liquid residues from debris samples. Petroleum Distillates: By-products of the refining of crude oil. Low boiling or light petroleum distillates (LPD) are highly volatile mixtures of hydrocarbons. These mixtures are sometimes called ligroin, petroleum ether, or naphtha. LPDs are used as cigarette lighter fluid, as copier fluid, and as solvents. Medium boiling petroleum distillates (MPD) are sometimes known as mineral spirits, and are used as charcoal starters, as paint thinners, as solvents for insecticides and other products, and as lamp oils. High Boiling or Heavy petroleum distillates (HPD) are combustible liquids such as kerosene and diesel fuel. pH: A number used to represent the acidity or alkalinity of an aqueous solution. pH 7 is neutral. Acids have a pH below 7, the lower the pH, the more acidic the solution. Bases have a pH above 7. The higher the pH, the more basic of alkaline the solution. Photoionisation Detector (PID): A type of detector used in chromatography which employs ultraviolet radiation rather than a flame to ionise compounds as they pass through a detector. Photoionisation detectors are particularly sensitive to aromatic compounds. Polarity: The measure of an electrical charge on a molecule. Most flammable or combustible liquids are nonpolar. Many water soluble compounds, including alcohols and acetone, are polar. Polymer: A large molecule consisting of repeating units of a monomer. Polymers may be natural, such as cellulose or synthetic such as most plastics. Programming: A method of gas chromatographic analysis which reproducibly raises the temperature of the column so as to allow better resolution of the components over a wide range of boiling points. Propane: An alkane having the formula C3H8. Propane is the major constituent of LP gas. Explosive limits of 2.4% to 9%. One cubic foot of propane has a heating value of 2500 BTUs. Pseudocumene: (1, 2, 4 - trimethyl benzene) A component of gasoline. Pyrolysis: The transformation of a substance into one or more other substances by heat alone without oxidation. Pyrophoric Distillation: The slow drying and passive pyrolysis of wood materials. Radiation: (1) Transfer of heat through electromagnetic waves from hot to cold.
(2) Electromagnetic waves of energy having frequency and wavelength. The shorter wavelengths (higher frequencies) are more energetic. The electromagnetic spectrum is comprised of
a) cosmic rays, b) gamma rays, c) x-rays, d) ultraviolet rays, e) visible light rays, f) infrared, g) microwaves and h) radio waves. Resolution: 1) In chromatography, a measure of the separation of components,
2) in spectroscopy, a measure of the ability of the instrument to detect individual absorbance peaks. Retention Time: The length of time required for a compound of component of a mixture to pass through a chromatographic column. Saturation: The state in which all available bonds of an atom are attached to other atoms. Alkanes are saturated. Olefins are unsaturated. Spalling: Destruction of a surface by frost, heat, corrosion, or mechanical causes. Concrete exposed to intense heat may spall explosively. Expansion and contraction of the concrete as well as vaporising moisture contained in the concrete contribute to this effect. It does not necessarily mean an accelerant was used. Spectrophotometer: A light measuring device which incorporates a monchrometer to isolate and project particular wavelengths of electromagnetic radiation through a sample, and a detector to measure the amount of radiation which has passed through the sample. Spectroscopy: An analytical technique devoted to the identification of the elements and the elucidation of atomic and molecular structure by measurement of the radiant energy absorbed or emitted by a substance in any of the wavelengths of the electromagnetic spectrum in response to excitation by an external energy source. Spontaneous Heating: Also known as Spontaneous combustion. Initially, a slow, exothermic reaction at ambient temperatures. Liberated heat, if undissipated (insulated), accumulates at an increasing rate and may lead to spontaneous ignition of any combustibles present. Spontaneous ignition occurs sometimes in haystacks, coal piles, warm moist cotton waste, and in stacks of rags coated with drying oils such as cottonseed or linseed oil. Styrene: Vinylbenzene. An aromatic compound having the formula C6H5C2H3. The monomer of polystyrene plastic. A common product of polymer pyrolysis. Substrate: Matrix. The material from which a substance to be analysed is removed. Sulfur: A nonmetallic yellow element. A constituent of black powder, sulfur burns readily when in powdered form. Terpenes: Volatile hydrocarbons which are normal constituents of wood. Thermal Conductivity Detector: A type of gas chromatographic detector which is sensitive to the change in the ability of the gases emerging from the column to conduct heat. A thermal conductivity (TC) detector is not as sensitive as a flame ionisation detector, but it is capable of detecting some molecules, such as water, which give no signal in FID. Thin Layer Chromatography (TLC): A procedure for separating compounds by spotting them on a glass plate coated with a thin (about 0.01 inch) layer of silica or alumina, and 'developing' the plate by allowing a solvent to move upward by capillary action. TLC is especially used for identifying and comparing materials which are highly coloured or which fluoresce under ultraviolet light. TLC is used extensively in explosive analysis and in the comparison of gasoline dyes. Toluene: Methylbenzene. An aromatic compound having the formula C6H5CH3. A major component of gasoline. Toluene has a flash point of 40°F and explosive limits of 1.2% to 7%. Turpentine:
1) Gum. The pitch obtained from living pine trees. A sticky viscous liquid.
2) Oil. A volatile liquid obtained by steam distillation of gum turpentine, consisting mainly of pinene and diterpene. Turpentine is frequently identified in debris samples containing burned wood. Vaporisation: The physical change of going from a solid or a liquid into a gaseous state. Volatile: Prone to rapid evaporation. Both combustible and noncombustible materials may be volatile. X-ray Diffraction: An analytical technique used to identify crystalline solids by measuring the characteristic spaces between layers of atoms or molecules in a crystal. X-ray diffraction can be very useful in the identification of explosive residues. X-ray Fluorescence: A spectromphotometric analytical technique used to identify crystalline solids by measuring the characteristic spaces between layers of atoms or molecules in a crystal. X-ray diffraction can be very useful in the identification of explosive residues. Xylene: Dimethylbenzene. An aromatic compound having the formula C6H4(CH3)2. Xylene is a major component of gasoline. A mixture of toluene and xylene is frequently used as an automotive paint thinner. Xylene is actually a mixture of three isomers, ortho, meta and para xylene, which have the methyl groups in different positions relative to each other on the benzene ring. The flash points of these isomers range from 81° to 115°F, is used to calibrate flash point testers. The explosive limits of xylene are 1.0% to 7.0%.

Employee Training and Documentation

The following section outlines the recommended training programs and documentation requirements for all fertilizer operations.

Employee Training: Employee training is one of the most important elements for ensuring a safe and profitable fertilizer operation.

Recommendations

Transportation of Dangerous Goods –Anhydrous ammonia and ammonium itrate are the only commonly used fertilizer products classified under the Transportation of Dangerous Goods regulations. Any facility that handles or transports these classified products must train staff in the requirements as defined by the Transportation of Dangerous Goods Act and Regulations.

Workplace Hazardous Materials

Information System (W.H.M.I.S.) – all staff must be trained in accordance with W.H.M.I.S. regulations. Specific attention should be paid to understanding a Material Safety Data Sheet (MSDS)

 Standard Operating Procedures – all staff must be trained to conduct all major tasks and functions in accordance with developed standard operating procedures.

Emergency Response Training – all staff involved in executing the emergency response plan must be trained to ensure an understanding of their duties.

First Aid/C.P.R. – an appropriate number of staff at the facility should be trained and certified in emergency first aid and cardiopulmonary resuscitation (CPR).

Safety Equipment Usage and Maintenance – all staff must be trained in the proper usage and maintenance of safety equipment.

Confined Workspace/Hot Work Training - any facility that requires employees to enter confined workspaces or undertake hot work must ensure those employees are properly trained before conducting those activities.

Occupational Health and Safety Rules – all staff must be made aware of the health and safety rules at a facility.

Documentation Requirements

There are a number of differrent types of documentation required for all fertilizer operations. Most provide information to ensure compliance to regulatory requirements while others serve to provide information to monitor operational effectiveness. Both are necessary to maintain a profitable and safe fertilizer operation.

Recommendations

1. Regulatory Information – regulatory information should include the Transportation of Dangerous Goods Act & Regulations, the Workplace Hazardous Materials Information System Act & Regulations, the Occupational Health and Safety Regulations and any other regulations applicable to the operation.

2. Standard Operating Procedures – a set of up-to-date standard operating procedures should be available at the facility that defines in a step-by-step manner how each major task or function is to be safely and effectively conducted.

3. Emergency Response Plans – a document detailing the plan for responding to emergencies such as a fire or major spill must be developed and updated regularly.

4. Material Safety Data Sheets (MSDS) –Material Safety Data Sheets must be available for each type of fertilizer stored and handled at the facility.

5. Licenses & Permits – all licenses and permits required to legally operate a fertilizer operation must be obtained and maintained.

6. Inspections – a copy of all inspections should be kept including any copies of follow-up on identified action items.

7. Training Records – copies of employee training records should be kept to adequately monitor and maintain training requirements.