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).
b.
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.
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.
4
