Labeling and Storage of Chemicals
Each container must be labeled with the identity of all hazardous chemicals and the appropriate hazard warnings. Whenever a chemical is transferred to an unlabelled container, a new label must be created and securely attached to the container.
The label on all stock chemicals must remain legible and securely fastened at all times. Never remove the original manufacturer’s label until the container is completely emptied of its contents and is ready to be either discarded or reused for another purpose. If the original manufacturer’s label becomes defaced in any way, immediately replace it with a new label containing all appropriate information. Place the date upon which the chemical was received on the original manufacturer’s label immediately upon receipt.
Chemicals Taken from Stock
A chemical removed from an original container and transferred to a smaller container for use must be properly labeled. The label must be legibly written in proper English. It must be attached to the new container in a permanent fashion which will reasonably protect it from damage during typical use. The label must contain the following information:
- Name of Chemical
- CAS Number
- Storage Requirement (if applicable)
- Warning of physical or health hazards
- Include the expiration date and receipt/opened date (if applicable)
Sample labels may be downloaded from the links below:
Definition of Hazards
Health Hazard: A chemical for which acute or chronic health effects may occur in exposed employees. The typical types of health hazards are:
- Reproductive Toxins
- Agents that may damage the lungs, skin, eyes or mucous membrane
Physical Hazard: A chemical for which there is scientifically valid evidence that it is a:
- Combustible liquid
- Compressed gas
- Organic peroxide
- Pyrophoric or unstable
These compounds may absorb oxygen from the air and react to form unstable peroxides. The following procedures must be followed for all peroxide forming chemicals:
- Date all peroxide-forming compounds when received and when opened.
- Inspect all containers of undetermined age prior to opening. If the container appears old, in bad condition or dried chemical residue is visible, do not attempt to open the container. If crystals are present or if liquid has been allowed to evaporate, do not touch or move the container.
- Order less than six months supply of these chemicals.
- Store these materials separately from oxidizers and mineral acids.
- When shelf life is exceeded, manage as hazardous chemical waste. Contact the environmental health and safety manager to request pickup of these chemicals.
Class B chemicals may be tested for peroxides using kits available from chemical suppliers using the procedure provided below. If tested and no peroxides are present, the chemical label may be redated and initialed, and the chemical kept for an additional 6 months.
There are four classes of peroxide forming chemicals that must be properly handled and labeled, they are:
Class A – Severe Peroxide Hazard
These must be disposed of within 3 months after opening. Manage as hazardous chemical waste. Contact the environmental health and safety manager at 718-488-1608 to request pickup of these chemicals.
Note: If crystals are present or if liquid has been allowed to evaporate, do not touch or move the container. Spontaneously decompose and may become explosive with exposure to air.
|Butadiene (liquid monomer)
Sodium amide (sodamide)
Chloroprene (liquid monomer)
Tetrafluoroethylene (liquid monomer)
|Potassium metal |
Class B – Concentration Hazard
Require external energy for spontaneous decomposition. Form explosive peroxides when distilled, evaporated or otherwise concentrated. These must be tested every six months after opening. A record of the test results, including the date and the actual test strip used, must be affixed to the container. If a Class B Peroxide Forming Hazard fail testing, manage as hazardous chemical waste. Contact the environmental health and safety manager to request pickup of these chemicals.
Click here for test procedure.
Diethylene glycol dimethyl ether (diglyme)
Ethylene glycol dimethyl ether (glyme)
Other secondary alcohols
Methyl isobutyl ketone
Class C – Shock and Heat Sensitive
Highly reactive and can auto-polymerize as a result of internal peroxide accumulation. The peroxides formed in these reactions are extremely shock and heat sensitive. Dispose of within 6 months of opening. Manage as hazardous chemical waste. Contact the environmental health and safety manager at 718-488-1608 to request pickup of these chemicals.
Vinyl chloride (gas)
Class D – Potential Peroxide Forming Chemicals
May form peroxides but cannot be clearly categorized in Class A, B, or C. If you suspect that peroxide crystals have formed on a container of any chemical, manage as hazardous chemical waste. Contact the environmental health and safety manager at 718-488-1608 to request pickup of these chemicals.