Glossary of Terms
EVM Series User Manual
137
Term
Definition
Hazardous Atmosphere
Means an atmosphere presenting a potential for death, disablement, injury, or acute
illness from one or more of the following causes:
a.
A flammable gas, vapor or mist in excess of 10% of its' lower explosive limit (LEL).
b.
An oxygen deficient atmosphere containing less than 19.5% oxygen by volume or an
oxygen enriched atmosphere containing more than 23.5% oxygen by volume.
c.
Airborne combustible dust at a concentration that meets or exceeds its LEL (airborne
combustible dust which obscures vision at five feet or less).
d.
An atmospheric concentration of any substance for which a dose or a permissible
exposure limit is published in Subpart G,
Occupational Health and Environmental
Control
, or in subpart Z,
Toxic and Hazardous Substances,
which could result in an
employee exposure in excess of its dose or permissible exposure limit, and that
could cause death, incapacitation, impairment of ability to self-rescue, injury or acute
illness.
e.
Any other atmospheric condition that is immediately dangerous to life or health
(IDLH).
IDLH (Immediately
Dangerous to Life and
Health )
Any condition that poses an immediate or delayed threat to life, or that would cause
irreversible adverse health effects or that would interfere with an individual's ability to
escape unaided from a confined space.
Lockout-Tagout
Placing locks or tags on the energy-isolating device (e.g. breaker boxes, control
switches, valves, etc.) to prevent the unauthorized re-energization of the device or
circuit while work is being performed by personnel. Tags shall indicate that the
energy-isolated device must not be operated until the tag is removed by the
individual(s) that installed the tag.
Material Safety Data
Sheet
Published for every chemical or substance that may be hazardous; if an exposure
limit has been published for a substance being discussed in an MSDS, that limit,
such as TWA or PEL, is required to be included in the MSDS publication. Ref: 29
CFR 1910.1200 (g)(2)(i)(C)(2) and (g)(2)(vi). TWA's and PEL's are not available for
most chemicals. There are simply too many chemicals, many of which have not gone
through the rigorous scientific study and peer review required. The absence of an
exposure limit for a substance should not be used to assume that a substance is not
hazardous.
