Separation from Source Systems

Separation from source systems are systems used for the purpose of keeping the dust "in" and the workers "out" (or visa versa). Depending on the scope and circumstance of the work activity, the use of a separation from source system may be the only engineering control practical to help reduce worker exposure.

Types of Separation from Source Systems

Operator Cab

An operator cab encloses the operator, keeping the operator separated from the dusty atmosphere.

Some types of equipment and machines use operator cabs to protect workers from dust. Most offer protection from weather and noise, some also protect from falling objects or rollover injury. Be sure to specify a cab equipped with a HEPA filtered air supply or air conditioning/heating system when these are offered.

Your Closed Pressurized Cab must meet the following criteria:

• Ventilation system that pressurizes the cab with a filter of MERV-16 or equivalent efficiency (95% efficient in the 0.3-10.0 µm range).
• Positive pressure maintained through continuous delivery of fresh air (minimum 0.05 - 0.25 inches of water).
• Heating and cooling capabilities.
• Door and window seals and closing mechanisms that are in good condition and work properly.
  • Good integrity of the gasket and seals within the filtration and pressurization system.

The following proper practices have been determined by BCCSA health and safety experts:

• Interior kept clean and free of dust.
• Cab maintained to manufacturer's recommendations including replacement of any damaged doors and window seals.
• Keep doors and windows closed at all times.
  • Opening the cab door to guide work substantially increases respirable dust concentrations even when no drilling is occurring and there are no visible dust clouds.

Operating Tips:

• Place intake air inlets away from dust sources to reduce overloading the filter with dust. Heaters or fans should be located higher in an enclosed cab where they are less prone to pick up dust from the floor of a cab/booth.
• Secondary and tertiary filters (MERV-16 or equivalent) inside the cab/booth increases worker protection by providing a secondary method of cleaning both the outside and inside recirculating air.