CHEMICAL STORAGE

General Considerations for Chemical Storage

All chemicals must be labeled with the full chemical name(s).

Carefully read the label before storing a hazardous chemical. The Material Safety Data Sheet (MSDS) will also provide any special storage information and incompatibilities.

Do not store unsegregated chemicals in alphabetical order or incompatible chemicals in close proximity to each other. Care must be exercised to ensure that the substance cannot accidentally come in contact with another with which it is incompatible. Such contact could result in a serious explosion or the formation of substances that are highly toxic or flammable or both. (This care must also be exercised when transporting, using and disposing of chemicals). Containment tubs may be used for segregation where space is limited.

Chemicals should be separately stored by chemical class as follows:

Solids

Liquids

Gases

Once separated into hazard classes, chemicals may be stored alphabetically. View additional examples of incompatible chemicals in the Appendix.

Use approved storage containers and safety cans for flammable liquids.

Use plastic spill trays under containers of strong corrosive reagents.

Do not store liquids above eye level.

Do not store chemicals on the floor.

Dispose of old chemicals promptly.

Ensure that all containers are properly labeled. For more information on chemical storage, contact your supervisor or the EHRS Department.  View additional information on labeling in the Hazard Communication Program.

Flammable and Combustible Liquid Storage

The storage of flammable and combustible liquids in a laboratory, shop, or building area must be kept to the minimum needed for research and operations. Flammable liquids have a flash point below 100 F. The storage of flammable liquids in the laboratory must not exceed a 2-day supply or 10 gallons, whichever is less. Excess amounts should be transferred to the Central Stockrooms. Whenever possible, flammable liquids should be stored in a flammable liquid storage cabinet. Flammable liquid storage cabinets are not intended for the storage of highly toxic materials, acids, bases, compressed gases, or pyrolitic chemicals.

1.
Store only compatible materials inside a cabinet.
2.
Flammables should not be stored in areas exposed to direct sunlight.
3.
Refrigerators, freezers and other cooling equipment used to store or cool flammable liquids must be "laboratory safe" or "explosion proof" and should be labeled as such. (i.e., This refrigerator has been designed to permit safe storage of materials producing flammable vapors)
4.
The quantities of flammable chemicals stored in the laboratory, shop, or building area should be kept to a minimum.

View Safe Handling of Flammables in Section VII for more information.

Chemical Stability

Stability refers to the susceptibility of the chemical to dangerous decomposition. Ethers, olefins, etc. form peroxides on exposure to air and light. Since these chemicals are packaged in an air atmosphere, peroxides can form even though the containers have not been opened. Write the date received and date opened on all containers of peroxide formers.

Unless an inhibitor was added by the manufacturer, closed containers of peroxide formers should be discarded after 1 year.

Open containers should be discarded within 6 months of opening.

In the Department of Chemistry, refilled cans of ether or peroxide formers should be so labeled and re-dated.

The label and Material Safety Data Sheet will indicate if a chemical is unstable.

Below are examples of materials that may form explosive peroxides. View additional compounds that form peroxides during storage.

acetal diethylene glycol isopropyl ether
cyclohexene dimethyl ether methyl acetylene
decahydronaphthalene dioxane tetrahydrofuran
diacetylene divinyl acetylene terahydronaphthalene
dicyclopentadiene ethyl ether vinyl ether
diethyl ether ethylene glycol-dimethyl ether (glyme) vinylidene chloride
2-propanol 2-butanol  

View additional information on the safe handling of reactive and peroxide forming chemicals in Section VII.  In addition, you can contact your laboratory supervisor or the EHRS Department.

Shock Sensitive Chemicals

Shock sensitive refers to the susceptibility of the chemical to rapidly decompose or explode when struck, vibrated or otherwise agitated.

Some chemicals become increasingly shock sensitive with age. Write the date received and date opened on all containers of shock sensitive chemicals. Unless an inhibitor was added by the manufacturer, closed containers of shock sensitive materials should be discarded after 1 year. Open containers of shock sensitive materials should be discarded within 6 months of opening.

The label and Material Safety Data Sheet will indicate if a chemical is shock sensitive. Wear appropriate personal protective equipment when handling shock sensitive chemicals.

The following are examples of materials that can be shock sensitive:

acetylides of heavy metals aluminum ophorite amatol
ammonium perchlorate explosive ammonium salt lattice
copper acetylide ammonium picrate cyclotrimethylenetrinitramine
dinitroglycerine cyanuric triazide dinitrophenolates
dipicryl sulfone dinitrophenol erythritol tetranitrates
fulminate of silver dipicylamine fulminating mercury
germane fulminating gold guanyl nitrosamino guanylidene
hexite guanyl nitrosamino hydrazine
hyrazoic acid guanyltetrazene hexanitrostilbene
lead salts hexanitrodiphenyl-amine lead mannite
mercury tartrate lead azide magnesium ophorite
nitrated polyhydric alcohol lead styphnate nitroaminotetrozole
nitroglycol mononitrotoluene nitrogen tri-iodide
organic amine nitrates nitrogen trichloride nitroparaffins
picratol nitroguanidine organic peroxides
potassium nitroaminotetrazole organic nitramines picryl chloride
sodatol picric acid silver azide
syphnic acid silver acetylide sodium dinitro-ortho-cresolate
trinitroanisole sodium amatol tetranitrocarbazole
trinitronaphthalene tetrazene trinitrobenzoic acid
tritonal trintrobenzene trinitrophloro-glucinol
trinitrophenetol urea nitrate  
ammonal ammonium nitrate butyl tetryl
calcium nitrate cyclotetramethylenetranitramine dinitroethyleneurea
dinitrophenyl hydrazine dinitrotoluene explosive mixtures
fulminate of mercury compounds fulminating platinum quanylidene
gelatinized nitrocellulose hexogen heavy metal azides
lead mononitro-resorcinate hydrazinium nitrate mannitol hexanitrate
lead picrate mannitol hexanitrate mercury oxalate
nitrated carbohydrate nitrated glucoside nitroglycerin
nitroglycide nitronium perchlorate nitrourea
picramic acid picramide picryl fluoride
polynitro aliphatic compounds silver styphnate silver tetrazene
sodium nitrate-potassium explosive mixtures sodium picramate tetrytol
trimonite trinitrocresol trimethylolethane
trinitrotoluene trinitroresorcinol  

This list is not all inclusive. Review the material safety data sheet for reactivity information concerning the chemicals you use.

View safe handling of reactive and peroxide forming chemicals in Section VII for more information.

COMPOUNDS THAT FORM PEROXIDES DURING STORAGE

Three Months Peroxide Hazard Generated During Storage:

Compound

Divinyl acetylene Sodium amide
Isporopyl ether vinylidene chloride
Potassium metal  

Twelve Months Peroxide Hazard:

Acetal Methylcyclopentane
Cumene Methyl acetylene (Propyne)
Cyclohexene Methyl isobutyl ketone
Diacetylene Tetrahydrofuran
Dicyclopentadiene Tetrahydornapthalene (Tetralin)
Dioxane Vinyl ethers
Ethyl ether  
Ethylene glycol dimethyl ether (glyme)        

Twelve Months Hazard Due to Peroxide Formation or Initiation of Spontaneous Polymerization *:

Acrylic acid Tetrafluoroethylene
Acrylonitrile Vinyl acetate
Butadiene Vinyl acetylene
Chloroprene Vinyl chloride
Chlorotrifluoroethylene Vinyl pyridine
Styrene  

Other Time-Sensitive Chemicals:

Chloroform (on contact with air) Sodium azide (on contact with metals)
Picric acid Picrylsulfonic acid (when dry)
Picryl Chloride (when dry)  
   
* When stored as a liquid, the peroxide forming potential of the Group 3 chemicals increases and certain of these monomers should then be considered as Group 1 compounds. (especially butadiene, chloroprene, and tetrafluoroethylene)

Compressed Gas Storage

Gases used in laboratories and other work areas are often conveniently supplied in cylinders at high pressure. Their use compounds potential chemical hazards. The rules for the proper use of compressed gases include:

Observe the following special rules when working with acetylene cylinders:

    1. Always store acetylene cylinders upright. They are partially filled with liquid acetone, which can be discharged instead of or along with acetylene.
    2. Do not use an acetylene cylinder that has been stored or handled in a non-upright position until it has remained in an upright position for at least 30 minutes.
    3. Ensure that the outlet line of an acetylene cylinder is protected with a flash arrester.
    4. Never exceed the pressure limit indicated by the warning red band of an acetylene pressure gauge.
    5. Use the correct kind of tubing to transport the gaseous acetylene. Some tubing materials such as copper form explosive acetylides.

 

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