Loading Docks
Most retail and commercial locations have at least one dedicated area where products and materials are loaded or unloaded onto vehicles. These areas are typically serviced by diesel vehicles, gasoline powered vehicles, and/or propane powered forklifts. All of these vehicles are powered by combustion engines which release exhaust gases into the air. Exhaust emissions tend to be highest around the loading dock area, since more lift trucks run under full load in the dock than in other sections of the warehouse or facility.
The main hazardous components of these exhaust gases is are carbon monoxide (CO) and nitrogen dioxide (NO2). These areas should be monitored by appropriate CO and NO2 sensors that will activate exhaust ventilation, alert employees when hazards cannot be cleared by ventilation, and ensure that employee exposure is always below the relevant permissible exposure limits.
Relevant Code Citations:
WAC 51-11C-403254
Section C403.2.6.4—Loading dock and parking garage ventilation system
controls.
C403.2.6.4 Enclosed loading dock and parking garage exhaust ventilation system control. Mechanical ventilation systems for enclosed loading docks and parking garages shall be designed to exhaust the airflow rates (maximum and minimum) determined in accordance with the International Mechanical Code.
Ventilation systems shall be equipped with a control device that operates the system automatically by means of carbon monoxide detectors applied in conjunction with nitrogen dioxide detectors. Controllers shall be configured to shut off fans or modulate fan speed to 50 percent or less of design capacity, or intermittently operate fans less than 20 percent of the occupied time or as required to maintain acceptable contaminant levels in accordance with the International Mechanical Code provisions.