Friday, 10 July 2015

Chemical Storage Guidelines

Chemical Storage Guidelines from The CDC

If you need a set of chemical storage guidelines meet OSHA and safety needs in your lab, school, manufacturing or storage facility, this page should provide the template you need.

Guidelines for Safe Chemical Storage

Safe chemical handling requires routine inspections of chemical storage areas and maintenance of stringent inventory control. The inherent hazards of chemicals can be reduced by minimizing the quantity of chemicals on hand. However, when chemicals must be used, proper storage and handling can reduce or eliminate associated risks. All chemical storage areas and cabinets should be inspected at least annually and any unwanted or expired chemicals should be removed.
Typical storage considerations may include temperature, ignition control, ventilation, segregation and identification. Proper segregation is necessary to prevent incompatible materials from inadvertently coming into contact. A physical barrier and/or distance is effective for proper segregation.
Proper storage information can usually be obtained from the Material Safety Data Sheet (MSDS), label, or other chemical reference material. As required by 29 CFR 1910.1200, an MSDS must be on hand for every hazardous chemical in your workplace. MSDSs must be provided by the manufacturer or distributor of chemicals purchased. MSDSs are also available through the LINDEN system, CDC's Chemical Tracking System. This system tracks CDC's chemical inventory and includes MSDSs for most chemicals in the inventory. The Internet can also be used to find MSDSs. For a fast search for an MSDS on the Internet, go to the CDC Intranet, select "Databases", then select "Scientific Information", and then "Material Safety Datasheets". This site provides specific manufacturer information as well as generic information.

Keys for safe chemical storage:
 

  • Ensure all containers of hazardous chemicals are properly labeled with the identity of the hazardous chemical(s) and appropriate hazard warnings.
  • Segregate all incompatible chemicals for proper storage of chemicals by hazard class. In other words, store like chemicals together and away from other groups of chemicals that might cause reactions if mixed.  
  • Do not store chemicals alphabetically except within a grouping of compatible chemicals.  
  • Flammable materials should be stored in an approved, dedicated flammable materials storage cabinet or storage room if the volume exceeds ten gallons. Keep cabinet doors closed.  
  • Chemicals should be stored no higher than eye level and never on the top shelf of a storage unit. Do not overcrowd shelves. Each shelf should have an anti-roll lip.  
  • Avoid storing chemicals on the floor (even temporarily) or extending into traffic aisles.  
  • Liquids should be stored in unbreakable or double-contained packaging, or the storage cabinet should have the capacity to hold the contents if the container breaks.  
  • Store acids in a dedicated acid cabinet. Nitric acid may be stored there also but only if it is kept isolated from all other acids.  
  • Store highly toxic or controlled materials in a locked, dedicated poison cabinet.  
  • Volatile or highly odorous chemical shall be stored in a ventilated cabinet. Chemical fume hoods shall not be used for storage as containers block proper air flow in the hood and reduce available work space.  
  • All chemicals should be labeled and dated upon receipt in the lab and on opening. This is especially important for peroxide-forming chemicals such as ethers, dioxane, isopropanol, and tetrahydrofuran. Solutions should be labeled and dated when prepared.  
  • Look for unusual conditions in chemical storage areas, such as:
      • Improper storage of chemicals
      • Leaking or deteriorating containers
      • Spilled chemicals
      • Temperature extremes (too hot or cold in storage area)
      • Lack of or low lighting levels
      • Blocked exits or aisles
      • Doors blocked open, lack of security
      • Trash accumulation
      • Open lights or matches
      • Fire equipment blocked, broken or missing
      • Lack of information or warning signs ("Flammable liquids", "Acids", "Corrosives", "Poisons", etc.)
         
  • First aid supplies, emergency phone numbers, eyewash and emergency shower equipment, fire extinguishers, spill cleanup supplies and personal protective equipment should be readily available and personnel trained in their use.  
  • Chemicals stored in explosion-proof refrigerators or cold rooms shall be sealed and labeled with the name of the person who stored the material in addition to all other required hazard warnings.  
  • Only compressed gas cylinders that are in use and secured in place shall be kept in the laboratory. All others, including empties, shall be sent to the compressed gas cylinder storage area for the particular facility.  
  • Keep all stored chemicals, especially flammable liquids, away from heat and direct sunlight.

Table 1. Examples of Incompatible Chemicals

The following list is not a complete listing of incompatible materials. It contains some of the more common incompatible materials. Always research materials you work with in order to work safely in the lab.

Chemicals listed in Column A should not be stored with or used near items in Column B.

Column A Column B
Acetic acid Chromic acid, nitric acid, hydroxyl compounds, ethylene glycol, perchloric acid, peroxides, permanganates
Acetic anhydride Hydroxyl-containing compounds such as ethylene glycol, perchloric acid
Acetone Concentrated nitric and sulfuric acid mixtures, hydrogen peroxide
Acetylene Chlorine, bromine, copper, fluorine, silver, mercury
Alkali and alkaline earth metals such as powdered magnesium, sodium, potassium Water, carbon tetrachloride or other chlorinated hydrocarbons, carbon dioxide, halogens
Ammonia (anhydrous) Mercury, halogens, calcium hypochlorite, hydrofluoric acid
Ammonium nitrate Acids, metal powders, flammable liquids, chlorates, nitrites, sulfur, finely divided organic or combustible materials
Aniline Nitric acid, hydrogen peroxide
Arsenical materials Any reducing agent
Azides Acids, heavy metals and their salts, oxidizing agents
Calcium oxide Water
Carbon, activated All oxidizing agents, calcium hypochlorite
Carbon tetrachloride Sodium
Chlorates Ammonium salts, acids, metal powders, sulfur, finely divided organic or combustible material
Chlorine dioxide Ammonia, methane, phosphine, hydrogen sulfide
Chromic acid and chromium trioxide Acetic acid, alcohol, camphor, glycerol, naphthalene, flammable liquids in general
Copper Acetylene, hydrogen peroxide
Cumene hydroperoxide Acids (organic or inorganic)
Cyanides Acids
Flammable liquids Ammonium nitrate, chromic acid, hydrogen peroxide, nitric acid, sodium peroxide, halogens, other oxidizing agents
Fluorine All other chemicals
Hydrides Water
Hydrocarbons (e.g., butane, propane, benzene) Fluorine, chlorine, bromine, chromic acid, peroxides
Hydrocyanic acid Nitric acid, alkalis
Hydrofluoric acid (anhydrous) Ammonia (aqueous or anhydrous)
Hydrogen peroxide Copper, chromium, iron, most metals or their salts, any flammable liquid (i.e., alcohols, acetone), combustible materials, aniline, nitromethane
Hydrogen sulfide Fuming nitric acid, oxidizing gases
Hypochlorites Acids, activated carbon
Iodine Acetylene, ammonia (aqueous or anhydrous), hydrogen
Mercury Acetylene, fulminic acid, ammonia
Metal hydrides Acids, water
Nitrates Acids
Nitric acid (concentrated) Acetic acid, acetone, alcohol, aniline, chromic acid, hydrocyanic acid, hydrogen sulfide, flammable liquids, flammable gases, copper, brass, any heavy metals
Nitrites Acids
Nitroparaffins Inorganic bases, amines
Oxalic acid Mercury and silver and their salts
Oxygen Oils, grease, hydrogen; flammable liquids, solids, or gases
Perchloric acid Acetic anhydride, alcohol, bismuth, paper, wood, grease, oils
Permanganates Concentrated sulfuric acid, glycerol, ethylene glycol, benzaldehyde
Peroxides, organic Acids (organic or mineral), avoid friction, store cold
Phosphorus, white Air, oxygen, alkalis, reducing agents
Potassium Carbon tetrachloride, carbon dioxide, water
Potassium chlorate Sulfuric and other acids, ammonium salts, metal powders, sulfur, finely divided organics, combustibles
Potassium perchlorate (see also chlorates) Sulfuric and other acids
Potassium permanganate Glycerol, ethylene glycol, benzaldehyde, sulfuric acid
Silver and silver salts Acetylene, oxalic acid, tartaric acid, ammonium compounds, fulminic acid
Sodium Carbon tetrachloride, carbon dioxide, other chlorinated hydrocarbons, water
Sodium nitrate Ammonium nitrate and other ammonium salts
Sodium peroxide Ethyl or methyl alcohol, glacial acetic acid, acetic anhydride, benzaldehyde, carbon disulfide glycerin, ethylene glycol, ethyl acetate, methyl acetate, furfural
Sulfides Acids
Sulfuric acid Chlorates, perchlorates, permanganates
Adapted from Prudent Practices in the Laboratory: Handling and Disposal of Chemicals, National Research Council, 1995, with additions from OHS.


Table 2. Basic Chemical Segregation

 
Hazard Class of Chemical Recommended Storage Method Examples Incompatibilities
Compressed gases - Flammable Store in a cool, dry area, away from oxidizing gases. Securely strap or chain cylinders to a wall or bench. Methane Hydrogen Acetylene Propane Oxidizing and toxic compressed gases, oxidizing solids.
Compressed gases - Oxidizing Store in a cool, dry area, away from flammable gases and liquids. Securely strap or chain cylinders to a wall or bench. Oxygen Chlorine
Bromine
Flammable gases
Compressed gases - Poisonous Store in a cool, dry area, away from flammable gases and liquids. Securely strap or chain cylinders to a wall or bench. Carbon monoxide
Hydrogen sulfide
Nitrogen dioxide
Flammable and/or oxidizing gases.
Corrosives - Acids Store separately in acid storage cabinet. Segregate oxidizing acids (i.e., Chromic, nitric, sulfuric, and perchloric acids) from organic acids Acetic acid Phenol
Sulfuric acid Chromerge
Nitric acid
Perchloric acid
Chromic acid
Hydrochloric acid
Flammable liquids, flammable solids, bases, oxidizers
Corrosives - Bases Store in separate corrosive storage cabinet. Store solutions of inorganic hydroxides in labeled polyethylene containers. Ammonium hydroxide
Sodium hydroxide
Calcium hydroxide
Flammable liquids, oxidizers, poisons, and acids
Flammable Liquids Store in flammable storage cabinet and away from sources of ignition. Store highly volatile flammable liquids in an explosion-proof refrigerator. Acetone Benzene
Diethyl ether Methanol
Ethanol Toluene
Glacial acetic acid
Acids, bases, oxidizers, and poisons
Flammable Solids Store in a separate dry, cool area away from oxidizers, corrosives, flammable liquids Phosphorus, yellow Calcium carbide
Picric acid
Benzoyl peroxide
Acids, bases, oxidizers, and poisons
General Chemicals - Non-reactive Store on general laboratory benches or shelving preferably behind glass doors and below eye level. Agar
Sodium chloride
Sodium bicarbonate
Most non-reactive salts
See specific MSDS.
Oxidizers Store in a spill tray inside a chemical storage cabinet. Separate from flammable and combustible materials. Ammonium persulfate
Ferric chloride
Iodine
Sodium hypochlorite
Benzoyl peroxide
Potassium permanganate
Potassium dichromate
The following are generally considered oxidizing substances: Peroxides, perchlorates, chlorates, nitrates, bromates, superoxides.
Separate from reducing agents, flammables, and combustibles.
Poisons/Toxic Compounds Store separately in vented, cool, dry area, in unbreakable chemically-resistant secondary containers and in accordance with the hazardous nature of the chemical. Aniline
Carbon tetrachloride
Chloroform
Cyanides
Heavy metals compounds, i.e., cadmium, mercury, osmium
Oxalic acid
Phenol
Formic acid
Flammable liquids, acids, bases, and oxidizers.


 See specific MSDS.
Water-Reactive Chemicals Store in dry, cool location, protect from water fire sprinkler. Sodium metal
Potassium metal
Lithium metal
Lithium aluminum hydride
Separate from all aqueous solutions and oxidizers.
Carcinogens Label all containers as "Cancer Suspect Agents". Store according to the hazardous nature of the chemical, using appropriate security when necessary. Benzidine
Beta-naphthylamine
Benzene
Methylene chloride
Beta-propiolactone
See specific MSDS.
Teratogens Label all containers as "Suspect Reproductive Hazard". Store according to the hazardous nature of the chemical, using appropriate security when necessary. Lead and mercury compounds
Benzene
Aniline
See specific MSDS.
Peroxide-Forming Chemicals Store in air-tight containers in a dark, cool, dry area. See Table 3 for recommended storage time limits. Diethyl ether
Acetaldehyde
Acrylonitrile
See specific MSDS.
Strong Reducing Agents Store in cool, dry, well-ventilated location. Water reactive. Segregate from all other chemicals. Acetyl chloride Thionyl chloride
Maleic anhydride
Ferrous sulfide
See specific MSDS.


Table 3. Suggested Storage Time Limits for Common Peroxidizable Compounds
 

Under proper conditions, these chemicals will form explosive peroxides which can be detonated by shock or heat.

MOST DANGEROUS: Discard after 3 months. Peroxide formation hazard during storage.
Diisopropyl ether
Divinyl acetylene
Isopropyl ether
Potassium metal
Sodium amide
Vinylidene chloride
DANGEROUS: Discard after one year. Peroxide formation hazard during storage and on concentration (i.e., distillation) of compound.
Acetal
Acetaldehyde
Cumene
Cyclohexene
Diacetylene
Dicyclopentadiene
Diethyl ether
1,4-Dioxane
Ethylene glycol dimethyl ether
Methyl acetylene
Methyl cyclopentane
Methyl isobutyl ketone
Tetrahydrofuran
Tetrahydronaphthalene
Vinyl ethers
DANGEROUS: Discard after one year. Peroxide formation causes initiation of hazardous polymerization.
Acrylic acid
Acrylonitrile
1,3-Butadiene
2-Butanol
Chloroprene Chlorotrifluoroethylene
Methyl methacrylate
2-Propanol
Styrene
Tetrafluoroethylene
Vinyl acetate
Vinyl acetylene
Vinyl chloride
Vinyl pyridine
 

Other Safety Tips:
 

  • Do not purchase these compounds in quantities greater than can be used in the specified storage time period.
  • Label containers with receiving, opening and disposal dates.
  • Ethers should be stored in the dark and under nitrogen if possible.
  • Always check for the presence of peroxides before distilling any peroxide-former.
  • Consult safety references (i.e., MSDSs) before working with peroxidizable compounds.
  • If old containers of peroxide-forming chemicals are found, do not move them. Contact the Office of Health and Safety for assistance in disposing of the container.

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