Basic Hazards





Compressed Gas

Reactive Chemicals

Highly reactive chemicals include those which are inherently unstable and susceptible to rapid decomposition as well as chemicals which, under specific conditions, can react alone, or with other substances in a violent uncontrolled manner, liberating heat, toxic gases, or leading to an explosion. Reaction rates almost always increase dramatically as the temperature increases. Therefore, if heat evolved from a reaction is not dissipated, the reaction can accelerate out of control and possibly result in injuries or costly accidents.

Air, light, heat, mechanical shock (when struck, vibrated or otherwise agitated), water, and certain catalysts can cause decomposition of some highly reactive chemicals, and initiate an explosive reaction. One must use specialized procedures and control equipment whenever working with reactive materials. These are described in the risk assessment section of this program.

Water reactives react violently with water. Many produce flammable hydrogen gas that can then ignite when mixed with air (alkali metals, organomethallic compounds and some hydrides). Others give off large amounts of heat when mixed with water resulting in a violent reaction if the heat produced is not sufficiency dissipated.

Pyrophoric materials ignite spontaneously when exposed to the oxygen and or moisture in air at or below 130oF. These must be stored under water, mineral oil or an inert dry atmosphere depending on the substance. Examples: phosphorus, titanium dichloride, tributylaluminum, sodium, and lithium hydride

Accidental contact of incompatible chemicals can result in:

Generation of heat (acids & bases)
Violent reaction (acrolein & acids or other catalyst)
Formation of toxic vapors or gases (cyanide salt & acid)
Formation of a flammable gas (alkali metal & water)
Fire or Explosion (perchloric acid & acetic anhydride)

Incompatible materials must be sufficiently segregated in storage to prevent mixing during fires, explosions, and natural disasters like earth quakes. Accidents with incompatible materials often occur during the commingling of wastes in laboratories.

The following compatibility database can be used to identify chemicals that should not be mixed (unless under control conditions) or stored together.

Note: attach to the compatibility database

An explosive is substance or mixture of substances that when initiated by heat, light, friction, impact, or detonation undergoes a rapid chemical reaction giving off large volumes of hot gases. The reaction usually involves a decomposition of the substance(s) but may be caused by a rapid polymerization. Fires typically accompany an explosion.

Explosives may detonate (create a high-pressure wave traveling between 1000-9000 meters/second) or deflagrate (rapid decomposition of explosive but little to no high-pressure wave).

Provide list of unstable shock sensitive materials

Oxidizing agents in addition to their corrosive properties, are powerful oxidizing agents and present fire and explosion hazards on contact with organic compounds and other oxidizable substances. Picture of several bottles of strong oxidizer adjacent to flammable solvent.

Organic peroxides are among the most hazardous substances used in the laboratory - both fuels and oxidizers in one. They are typically low power explosives and very easy to initiate through sparks or shocks. Picture of organic peroxide bottle

Provide list of high energy oxydizers

Some materials, such as ethers, form peroxides when exposed to air or light. Date these containers when new and dispose as hazardous waste within six months.

Provide list of peroxide formers