Guidance Document
Reactive Chemicals

[This is a brief and general summary. Read the full MSDS for more details before handling.]

Introduction: The class of reactive chemicals includes polymerizable compounds, shock sensitive
materials, organic peroxides, peroxidable chemicals, air-reactive and water-reactive chemicals.

Polymerization Reactions: Polymerization is a chemical reaction in which two or more molecules of a
substance combine to form repeating structural units. Some polymerization reactions may liberate
uncontrolled or extreme heat. Examples include the polymerization of styrene or methacrylates.

Shock-sensitive Materials: Shock-sensitive materials are explosive and are sensitive to heat or
shock. Examples include dry picric acid, fulminates, dry benzoyl peroxide, ammonium perchlorate, and
compounds with functional groups of acetylide, azide, diazo, nitroso, ozonide.

Organic Peroxides: Organic peroxides are often used as reaction catalysts. Peroxides tend to be
unstable. Hazards are increased in contact with organic combustible material. Organic peroxides must
be protected against heat, shock, friction, contamination, sources of ignition. Many organic peroxides
are unstable at room temperature and should be stored under refrigeration. Follow specific
manufacturer's instructions for each substance.

Peroxide-Forming Compounds: Peroxide-forming compounds are unusually susceptible to
oxidation. Special storage and handling is used to minimize the formation and concentration of unstable
peroxides, which could present an explosion hazard. Peroxides may be formed by reaction with oxygen
in the air. This can be avoided by maintaining an inert gas atmosphere in the container's vapor
space. Store these materials at low temperature and in opaque containers. Avoid concentration during

distillation or evaporation. Types of chemicals which may form peroxides include aldehydes, ethers (esp.
cyclic and those derived from primary and secondary alcohol groups), compounds with benzyllic H
atoms, vinyl and vinylidine compounds. Click here for more detail. Minimize inventory and retention
time of peroxide-forming compounds.

Air-Reactive Chemicals: Air-reactive chemicals (pyrophoric compounds) can ignite spontaneously in the
presence of air. Examples are diethylzinc, triethylaluminum, many organometallic compounds. Store
pyrophoric materials away from other chemicals. Frequently check the integrity of containers of
pyrophorics. Minimize inventory. Contact EHS if the container is corroded or damaged.

Water-Reactive Chemicals: Water-reactive materials react violently with water to create one or more of
the following hazards: liberation of heat which may cause ignition of the chemical or nearby
flammables; release of a flammable, toxic or oxidizing gas; release of metal oxide fumes; formation of
corrosive acids. Examples of water-reactive materials include alkali metals (Li, Na, K), silanes, anhydrous
aluminum chloride, anhydrides. Store water-reactive chemicals in a cabinet away from water sources,
such as sinks, emergency showers and chillers.

Health Hazards: The reactive chemicals are grouped primarily because of the physical hazards
associated with use and storage. The chemicals may have additional acute or chronic health effects. Be
sure to read the MSDS. Contact EHS with any questions .