Table

Controls present in addition to

Carbon monoxide

Operation

natural ventilation

concentration

in PPM*

Three materials handling vehicles were operated in a 100,000 cubic-foot

Intermittent exposure ...................

200

warehouse room. The three drivers and two other workers were exposed

approximately 3 hours daily.

Gasoline-powered motor-generator units were operated indoors .............

a. Mechanical-exhaust tailpipe

100-150

extensions (15-20 cubic feet per

minute of air removed through

each extension).

Mechanical

general

ventilation by means of two large

wall exhaust fans.

Machine gun firing of 20-and 30-mm ammunition was performed by 40

a. Local-exhaust ventilation at

500

persons indoors. The total time of exposure for each person averaged 1

some firing positions.

hour per day. Occasionally special tests increased the exposure time to 5 to

b. Intermittent exposure.

6 hours per day.

a. Gravity-exhaust hood over

200

Hand-forging metal parts was performed by one man approximately 8 hours

the forge.

per week.

b. Mechanical general ventilation

by means of a wall-exhaust fan.

c. Intermittent exposure.

*Parts per million parts of air.