Engineering Controls: Methods of controlling employee exposure to safety and health hazards
by modifying the source of exposure or reducing the quantity of contaminants released into the
work area. Examples include piping, containment, ventilation, filtration and shielding.
Engulfment: The surrounding and effective capture of a person by a liquid or finely divided
(flowable) solid substance that can be aspirated to cause death by filling or plugging the
respiratory system, or that can exert enough force on the body to cause death by strangulation,
constriction, or crushing.
Entry Permit (Permit): The written document that allows and controls entry into a confined
space. It is a systematic evaluation of the confined space; it describes purpose of entry,
authorized personnel, hazards, work controls and equipment.
Entry Supervisor: The person (such as the employer, foreman, or crew chief) who determines if
acceptable entry conditions are present at a confined space, authorizes entry, oversees entry
operations, and terminates entries as required.
Exclusion Zone: A controlled area, located on the site, where contamination is either known or
expected to occur and where the greatest potential for exposure exists. Also known as the "Hot
Facility: Any DOE installation or portion of an installation operated, funded, or otherwise
controlled by EM-40.
Hazard: An act, condition, or phenomenon posing a source of actual or potential physical,
Hazard Evaluation: A process to assess the severity, and likelihood of exposure to known,
and/or potential occupational safety and health hazards, at or in the work environment.
Hazardous Atmosphere: An atmosphere that may expose employees to the risk of death,
incapacitation, impairment of ability to self-rescue (that is, escape unaided from a confined space),
injury, or acute illness from one or more of the following causes:
Flammable gas, vapor, or mist in excess of 10 percent of its lower flammable limit (LFL);
Airborne combustible dust at a concentration that meets or exceeds its LFL; NOTE: This
concentration may be approximated as a condition in which the dust obscures vision at a
distance of 5 feet (1.52 m) or less;
Atmospheric oxygen concentration below 19.5 percent or above 23.5 percent;