Health & Safety Terms and Abbreviations

Health, Safety and Environment has its own terms, acronyms and abbreviations.
In some cases the terms occur in everyday speech but, in Health and Safety, some have different shades of meaning to their common usage.
We have attempted to express our definitions in laymen's terms and therefore should not be assumed to have any legal standing.

Health and Safety Terms

Accident	An undesired event resulting in death, injury, damage to health, damage to property or other form of loss
Abnormal Event	An unplanned, unusual, occurrence or emergency
Absorption	Taking a substance into the body by penetration through intact skin - one of the Routes of Entry
Adaptation	The limited ability for people to tolerate small departures from optimal conditions (equipment design, environment, etc) without significantly affecting performance, for example _ use of a chair that is a little too high or a little too low
Aerosols	Substance dispersed into the air such that the droplets or particles remain in suspension for a significant period of time
Air Exchange Rate	The rate at which inside air is replaced by outside air. The rate may be expressed as the number of changes of air per unit of time (e.g. Air Changes per Hour - ACH) or the volume of air exchanged per unit of time (e.g. Cubic Feet per minute (CFM)
Allergen	Substance causing an allergic reaction in a person who is sensitive to that substance
Ambient	Surrounding, e.g. Ambient temperature usually means the outside temperature
Anthropometric Dimensions	The dimensions of the human body. These may be static measurements (i.e. when the subject standing or seated) or functional (i.e. when the person assumes an unnatural posture)
Apparent Loudness	Measurement in decibels of sound pressure measured against the threshold of hearing, being 0 decibels. The pain threshold is 120 decibels and an increase of 3 decibels is perceived as doubling in loudness
Appointed Person	A person who has been nominated to take charge in the event of an accident or illness (and support designated first aiders if present) and has been trained in basic lifesaving first aid techniques (See Designated Person)
Approved Code of Practice	A code of practice, associated with specific regulations, that has been approved by the Health & Safety Commission. A Code of Practice is seen as the accepted standard and can be used as evidence in a court of law. It is not mandatory to follow a Code of Practice but, to be acceptable, any alternative must be demonstrated to be of equal measure or better.
Asbestos	Hydrated magnesium silicate in fibrous form
Audible Range	Normal hearing frequency, approximately 20 Hz to 20,000 Hz

Background Level	The normal or typical level of a chemical in the environment, often referring to the naturally occurring level
Best Practice	A standard of risk control that is above the legal minimum (See Good Practice)
Biological Agent	A living organism or something made from a living organism that can be used beneficially (e.g. to prevent or treat disease) or maliciously (e.g. germ warfare)
Boiling Point	Temperature at which a liquid changes to a gas at normal atmospheric pressure

Carcinogen	Substance that is known or suspected of causing cancer
Carpal Tunnel Syndrome	A chronic disorder of the hand and wrist possibly resulting from repetitive work involving repeated wrist flexion or extension
Catalyst	A substance that initiates or accelerates a chemical reaction without itself being affected by the reaction
Central Nervous System	The part of the nervous system that includes the brain and spinal cord
Cervical Spine	The uppermost 7 vertebrae of the spine which, being very delicate, is prone to degenerative processes
Chronic	Occurring over an extended 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
Combustible Liquid	Liquid with a flash point above 37.8 C (100° F)
Common Law	Source of law that is not written in statute but which has been developed through judicial precedent. A breach of common law could result in a criminal offence or a civil action for damages.
Competent Person	A person who is appropriately trained, qualified, experienced and skilled to undertake specific health and safety duties without risk to their own safety or that of others
Compliance	The act or process of fulfilling requirements
Compressed Gas	Substance that is a gas at normal pressure and room temperature but is held in a pressurised container resulting in it becoming a liquid
Concentration	The quantity of one substance contained in another substance e.g. the amount of salt dissolve in sea water
Contaminant	Substance - usually undesirable - in another substance, product or space where it is not normally found, e.g. environmental pollutants
Contrast	The difference in brightness between the subject (e.g. text) and the background against which it is viewed
Control of Substances Hazardous to Health	Regulations promoting safe working with potentially hazardous chemicals
Corrosive	Substance that causes destruction of another substance, including human tissue
Cryogenics	Materials that exist at extremely low temperatures, e.g. liquid nitrogen
Cutaneous	Pertaining to or affecting the skin

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)
Display Screen Equipment	Any alphanumeric or graphic display screen regardless of the process employed to display the information. Typical examples include computer monitors and microfilm viewers
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

Employment Medical Advisory Service	Part of the Health and Safety Executive, offering advice on work related health issues and on people with health problems returning to work.
Ergonomics	The application of information about human characteristics to design applications, e.g. equipment, tools, work tasks, with the aim of improving safety and efficiency

Fatigue	Transient reduced ability to work as a result of previous activity, resulting in reduced efficiency
Fires	Class A - Fires in ordinary combustible materials such as wood, cloth, paper, etc. Class B - Fires in flammable liquids and liquefiable solids or electrical fires Class C - Fires involving gases. Class D - Fires involving combustible metals such as potassium or sodium Class F - Fires involving cooking oils or fats
Fire Prevention	Precautions designed to avoid an outbreak of fire, reduce the potential for fire to spread and safeguard persons and property in the event of fire
Flammable Gas	Gas that when mixed with air forms a flammable mixture at ambient temperature and pressure
Flammable Liquid	Liquid with a flashpoint below 100°F (37.8°C)
Flammable Solid	Solid that is liable to cause fires through friction, absorption of moisture, etc. or which can be readily ignited
Flash Point	The lowest temperature at which a flame will propagate through the vapour of a combustible material
Freezing Point	Temperature at which a liquid becomes a solid, at normal atmospheric pressure

Glare	When a portion of the visual field has a significantly higher luminance than its surroundings, resulting in reduced contrast
Good Practice	HSE Definition: Those standards for controlling risk which have been judged and recognised by the HSE as satisfying the law when applied to a particular relevant case in an appropriate manner. (See Best Practice)

Hazard	Potential for harmful effects
Health And Safety Executive	Organisation responsible for proposing safety regulations throughout the UK. It is responsible for enforcing, statute, regulations, approved codes of practice and guidance.

Illuminance	A measure of the amount of light falling on a particular point, measured in Lux
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 that an offence has been committed, what action needs to be taken, the reason for the action and the time deadline by which it must be taken.
Incident (or Near Miss)	A generic term for those events that do not cause harm but which might have done so under different circumstances
Ingestion	Taking a substance into the body through the mouth, for example in the form of food or drink - one of the Routes of Entry
Inhalation	Taking a substance, typically in the form of gases, fumes, vapours, mists, aerosols or dusts, into the body by breathing it in - one of the Routes of Entry
Inhibitor	A substance which, when added to another substance, prevents or slows down an unwanted change or reaction
Injection	Taking a substance directly into the body by puncturing the skin, for example with a needle - one of the Routes of Entry
Irritant	A substance that produces inflammation when it makes contacts with the skin, eyes, nose, or respiratory system

Liquid Petroleum Gas	LPG consists of commercial Butane, Propane or a mixture of the two. Major hazards are fire and explosion, though asphyxiation is also a danger in low lying areas due to LPG being heavier than air
Lock-Off	Mechanisms that, as part of engineering controls, are designed to prevent potentially dangerous equipment from being energised during routine maintenance and/or repair work
Lumbar Spine	The lower 5 vertebrae of the spine, situated below the thoracic vertebrae and above the sacral vertebrae
Luminance	A measure of the amount of light emitted or reflected by a surface in a given direction
Lux	Unit of measurement of illumination, equivalent to lumen per square

Manual Handling Operations	Tasks that require a person to exert force in order to lift, lower, push, pull, move, carry, hold or restrain an object
Material Data Safety Sheet	Contain information on the hazards associated with a chemical, along with guidance on its safe use
Mutagen	Something that is able to cause a mutation (or genetic change) in a living cell

Narcotic	A substance that has the potential to affect the nervous system by, for example, inducing drowsiness, stupor or insensibility
Near Miss	See "Incident"
Negligence	Can be either the omission to do something that a reasonable person would do when guided by those considerations that ordinarily regulate the conduct of human affairs, or the 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. DDT) that do not easily break down into less hazardous substances
Parts per Billion	Specifies the concentration by volume of a substance dispersed in another substance
Parts Per Million	Specifies the concentration by volume of a substance dispersed in another substance
Permit to Work	Formally delivered criteria for control/risk reduction when undertaking pre-planned work that is hazardous, either because of its location or the nature of the activity.
Planning Supervisor	Responsible under Construction (Design and Management) Regulations for coordinating the health and safety aspects of the design, preparation of a health and safety plan at the pre-tender stage and preparation of the health and safety file.
Policy	A statement of an organisation _ s strategy for achieving a safe and healthy working environment and the responsibility, organisation and arrangements for pursuing and implementing the strategy
Preventive Maintenance	Maintenance (including inspection, cleaning, and repair) of equipment on a regular basis that is sufficient to prevent unplanned failure
Prohibition 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 that presents a risk of serious personal accident. The effect of the Prohibition Notice is to stop the activity from starting or to cause it to cease if it has already started.

Regulation	A statutory device made under a general provision that is contained in an act of parliament. Regulations themselves are approved by parliament and are generally absolute legal standards.
Residual Current Device	An electrical safety device that constantly monitors the electric current flowing through a circuit. If it senses a loss of current where electricity is being diverted to earth (as might happen if a person touches a live conductor), it rapidly shuts down the power.
Relative Humidity	The percentage ratio of vapour pressure in the atmosphere compared to the saturated vapour pressure at that temperature
Risk	A quantifiable expression of the likelihood of injury or harm resulting from a hazard
Risk Assessment	A formal estimation 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
Routes of Entry	The various ways in which toxic substances may enter the body, including; Absorption, Ingestion, Inhalation, Injection and Eye-splashes

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
Safety Culture	A general term for the degree to which the culture of an organisation promotes and cooperates with safe and healthy work practices
Self-Assessment	Assessments performed by individuals (or organizations) to determine how safely they are working and meeting their health & safety responsibilities toward themselves and others
Sensitization	Development, over time, of an allergic reaction to a substance
Sensitizer	Substance that may cause a person to develop an allergic reaction after repeated exposure
Solubility	Ability of a substance to dissolve in a liquid
Solvent	Substance that is capable of dissolving another substance
Stress	That which might result when an event or situation places increased demand on a person's mental or emotional resources. Sources of stress may arise from domestic or social situations as well as occupational circumstances. The individual's response to such situations can lead to health and safety related problems such as depression, cardiovascular disease, musculo-skeletal disorders and an increased tendency to be accident-prone.
Synovial Fluid	A viscous fluid that lubricates joints and tendon sheaths

Tenosynovitis	Inflammation and swelling of the tendon sheaths, usually of the wrist or hand, potentially caused by repetitive movements such as very high-speed typing rates
Thoracic Spine	The mid and upper regions of the back, comprising 12 vertebrae that occupy the same level as the rib cage
Toxic	Substances that cause irritation of are otherwise harmful to health, such as carcinogens and poisons
Toxicity	The potential for a substance to be harmful to health

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

Vapour	The gaseous form of a substance that is normally liquid or solid at room temperature
Ventilation	Movement of air, usually associated with the introduction of fresh air
Volatility	Ability of a substance to evaporate

Workplace Exposure Limit	Established concentration of a substance that, if not exceeded, will not normally result in adverse effects to persons who are exposed
Workstation	The combination of equipment items that a user requires to fulfil their allotted tasks. In Display Screen Equipment terms, the components might include: desk, chair, computer monitor, keyboard, processing unit and such ancillary equipment as required by the work, such as document holder or telephone.
Wrist Extension & Flexion	Bending movement of hand and wrist from the horizontal (up or down respectively). Causes tendons to curve around structures in the wrist, possibly causing friction, which can in turn result in fatigue or injury