Engineering Controls - est55030138

DOE-EM-STD-5503-94

13.5.1. Engineering Controls

Engineering controls are those controls which eliminate or reduce the hazard through

implementation of sound engineering practices.

Ventilation is one of the most common engineering controls used in confined spaces. When

ventilation is used to remove atmospheric contaminants from the confined space, the space

should be ventilated until the atmosphere is within the acceptable ranges. Ventilation should be

maintained during the occupancy if there is a potential for the atmospheric conditions to move

out of the acceptable range. When ventilation is not possible or feasible, alternate protective

measures or methods to remove air contaminants and protect occupants should be determined by

the qualified person prior to authorizing entry. Conditions regarding continuous forced air

ventilation should be used as follows:

Employees should not enter the space until the forced air ventilation has eliminated any

hazardous atmosphere,

Forced air ventilation should be so directed as to ventilate the immediate areas where an

employee is or will be present within the space,

Continuous ventilation is maintained until all employees have left the space, and

Air supply for forced air ventilation should be from a clean source.

13.5.2. Work Practice (Administrative) Controls

Work practice (administrative) controls are those controls which eliminate or reduce the hazard

through changes in the work practice (e.g., rotating workers, reducing the amount of worker

exposure, housekeeping). Confined spaces should be cleaned/decontaminated of hazardous

materials to the extent feasible before entry. Cleaning/decontamination should be the preferred

method of reducing exposure to hazardous materials. Where this is not practicable, PPE should

be worn by the entry personnel to provide appropriate protection against the hazards which may

be present.

13.5.3. Personal Protective Equipment (PPE)

If the hazard cannot be eliminated or reduced to a safe level through engineering and/or work

practice controls, PPE should be used. A qualified person should determine PPE needed by all

personnel entering the confined space, including rescue teams. PPE which meet the

specifications of applicable standards should be selected in accordance with the requirements of

the job to be performed.

13.6. ENTRY PERMITS

The Confined Space Entry Permit is the major tool in assuring safety during entry in confined

spaces with known hazards or with unknown or potentially hazardous atmospheres. The entry

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