SILICA IN THE WORKPLACE
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365-AXJ-01-iGDO © 2020, Workplace Safety & Prevention Services (WSPS)
1 877 494 WSPS (9777) | 905 614 1400 | wsps.ca
WSPS.CA
Local exhaust ventilation is usually required when existing equipment is enclosed. Air containing
silica dust should be passed through a dust collector prior to being drawn through the fan.
Waste air should be exhausted through a stack to the outdoors. Exhausted air must comply with
environmental emission standards.
In all cases in which mechanical exhaust ventilation is installed, make-up air must be provided.
Make-up air is required to maintain the air balance within the building. Suction fans will be
"starved" if not provided with sufficient make-up air.
B. WORK PRACTICES AND PROCEDURES
The practices and procedures employed in the workplace are critical to the control of contaminants
such as crystalline free silica. Installed engineering controls are only as effective as the practices and
procedures built around them.
1. Work Procedures
Procedures must ensure the safe handling, use and disposal of materials containing crystalline
free silica. In order to ensure consistency when training new employees, all procedures should be
documented in writing.
When preparing written procedures, the task should be examined to ensure that the methods to be
included will minimize exposure when properly carried out.
Workplace procedures should address normal operating conditions as well as situations arising from
accidental release of material into the workplace air.
2. Housekeeping
All areas of the plant should be kept clean and free from settled dust. This is a difficult task in
situations in which dusty materials are being handled continually. Settled dust contains material,
which given appropriate conditions such as vibration or other mechanical disturbance, can become
airborne.
Procedures for removing settled dust must be reviewed carefully to ensure that they do not
contribute to the dust problem. In general, the following practices are recommended:
– vacuum cleaning
– wet sweeping (if compatible with other constituents in the dust)
– no dry sweeping
– no air blowing
