Important Methyl Ethyl Ketone Peroxide (MEKP) Safety Information
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Important Methyl Ethyl Ketone Peroxide (MEKP)
Safety Information
MEKP is among the more hazardous materials found in
commercial channels. Proper handling of the “unstable
(reactive)” chemicals presents a definite challenge to
the plastics industry. The highly reactive property which
makes MEKP valuable to the plastics industry in produc-
ing the curing reaction of polyester resins and gel-coats
also produces the hazards which require great care and
caution in its storage, transportation, handling, process-
ing and disposal.
Workers must be thoroughly informed of the hazards
that may result from improper handling of MEKP, espe-
cially in regards to contamination and heat. They must
be thoroughly instructed regarding the proper action to
be taken in the storage, use and disposal of MEKP and
other hazardous materials used in the laminating opera-
tion.
MEKP is flammable and potentially explosive, as
well as potentially damaging to the eyes and skin.
Read material manufacturer’s warnings and
material MSDS to know specific hazards and pre-
cautions related to MEKP.
Contaminated MEKP can become explosive. Pre-
vent contamination of MEKP with other materials,
which includes, but is not limited to polyester over-
spray, polymerization accelerators and promoters,
and non-stainless metals. Even small amounts of
contaminates can make MEKP explosive. This reac-
tion may start slowly, and gradually build-up heat,
which can accelerate until fire or an explosion result.
This process can take from seconds to days.
Heat applied to MEKP, or heat build-up from con-
tamination reactions can cause it to reach what is
called its Self-Accelerating Decomposition Tempera-
ture (SADT), which can cause fire or explosion. Spills
should be promptly removed, so no residues remain.
Spillage can heat up to the point of self-ignition. Dis-
pose in accordance with manufacture’s recommenda-
tion.
Store MEKP in a cool, dry and well-ventilated area
in the original containers away from direct sunlight
and away from other chemicals. It is strongly recom-
mended that the storage temperature remain below
86° F (30° C). Heat will increase the potential for
explosive decomposition. Refer to NFPA 432. Keep
MEKP away from heat, sparks and open flames.
Current catalysts are premixed and do not require
any diluents. Graco strongly recommends that dilu-
ents not be used. Diluents add to the possibility of
contaminates entering the catalyst system. Never
dilute MEKP with acetone or any solvent since this
can produce an extremely shock-sensitive compound
which can explode.
Use only original equipment or equivalent parts
from Graco in the catalyst system (i.e.: hoses, fittings,
etc.) because a hazardous chemical reaction may
result between substituted parts and MEKP.
To prevent contact with MEKP, appropriate per-
sonal protective equipment, including chemically
impermeable gloves, boots, aprons and goggles are
required for everyone in the work area.
