Example 15: Ensuring Adequate Task Hazard Analysis and Pre-Job Briefings to Fully Identify Hazards

DOE-STD-1120-2005/Vol. 2

Example 15:

Ensuring Adequate Task Hazard Analysis and Pre-Job Briefings to Fully Identify

Hazards

A work task involved the installation of a temporary enclosure for asbestos abatement consisting of

double plastic attached to wooden 2 inch x 4 inch framing. The enclosure consisted of panels that were

glued together to form a seamless barrier. This glue produced a volatile off-gas during drying. This

volatile off-gas was to be controlled by the operation of the temporary exhaust system, which was

attached to the enclosure.

During the installation, the workers inside the enclosure noted that the temporary exhaust separated the

plastic panel seams before the glue dried. To prevent this, the temporary exhaust was shut off. During a

routine inspection, a safety technician noted that the exhaust was not operating, but worker activities were

continuing, including the use of unshielded electric drills to attach wooden framing. A portable explosive

gas monitor was used by the technician to determine the presence of volatile gases. The measurement

was off-scale. The technician ordered an immediate cessation of activities and evacuation of the area.

The temporary exhaust was restarted and the plastic seams began to separate again. A review of this

event revealed the following:

(1) The task hazard analysis had addressed the volatile off-gas condition and the temporary exhaust

was provided to mitigate this condition. However, the use of unshielded electric motors in this

environment had not been identified.

(2) The workers had not been briefed adequately on the hazards presented by the volatile off-gas nor

on the importance of maintaining adequate ventilation during the drying of the glue, resulting in a

potentially explosive atmosphere.

FEEDBACK AND IMPROVEMENT

Example 16:

Self-Assessments Lead to Discovery of Deficiency

A quarterly self-assessment indicated that workers were being exposed to higher than expected levels of

airborne contamination when performing apparently routine decontamination of an area within a surplus

plutonium facility. As part of the self-assessment, the readings from building constant air monitors

(CAMs) were reviewed and the information was analyzed for trends. Although no worker had been

exposed to levels above DOE limits contained within 10 CFR 835, it became apparent that the levels from

this area were consistently higher than any other area within the building. Accordingly, an investigation

team, comprised of the cognizant engineer, a health physicist, and a worker, assembled to determine the

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