Clearly, the above level of material segregation is complex and time consuming for chemical storage in most research laboratories. What should be required as a minimum, however, is to establish and separate chemicals according to similar hazards, such as flammability, corrosivity, sensitivity to water or air, and toxicity. The following major categories of chemicals, each of which will be discussed in greater detail, are strongly recommended:
- Flammables
- Oxidizers
- Highly Reactives
- acids
- bases
- Corrosives
- Extreme Toxics/Regulated Materials
- Low Hazard
One problem with the implementation of this type of system of assigning chemicals to a specific storage area based on chemical hazards, is the actual identification of the hazards themselves. Recent legislation has made this task somewhat easier since all chemical manufacturers are now required to list all hazards on outgoing chemical containers and each chemical must be accompanied by a Material Safety Data Sheet (MSDS). The chemical label thus furnishes a quick method of determining whether the material is a fire hazard, health hazard or reactivity hazard. The MSDS furnishes more detailed information regarding toxicity exposure levels, flashpoints, required safety equipment and recommended procedures for spill containment.
Another problem with the implementation of this system is that most chemicals have multiple hazards and a decision must be made as to which storage area would be most appropriate for each specific chemical. First you have to determine your priorities! When establishing a storage scheme, the number one consideration should be the flammability characteristics of the material. If the material is flammable, it should be stored in a flammable cabinet. If the material will contribute significantly to a fire (i.e., oxidizers), it should be isolated from the flammables. If there were a fire in the lab and response to the fire with water would exaggerate the situation, isolate the water reactive material away from contact with water. Next look at the corrosivity of the material, and store accordingly. Finally, consider the toxicity of the material, with particular attention paid to regulated materials. In some cases, this may mean that certain chemicals will be isolated within a storage area, for instance, a material that is an extreme poison but is also flammable, should be locked away in the flammable storage area to protect it against accidental release. There will always be some chemicals that will not fit neatly in one category or another, but with careful consideration of the hazards involved, most of these cases can be handled in a reasonable fashion.
The earlier example of a detailed storage organization based on incompatibility, is perhaps too complex for most research labs, but all labs are capable of establishing a minimum storage scheme based on hazard classes. For the safety of all personnel and to protect the integrity of the facilities, hazardous materials must be segregated.