Page 39 - OHS, May 2020

If tests show that the facility has com- bustible dust, it is required by NFPA 652 to complete a dust hazard analysis (DHA) of their dust collection systems. They also need to keep this report on file to show when requested by the local fire marshal or other authority having jurisdiction. In addition, explosion venting equipment must be inspected at least annually based on the documented operating experience.
How are vents and discharge ducts sized to make sure they are right for a dust collector?
Chapters seven through nine of NFPA 68 provide the calculations to use for properly sizing explosion vents, vent discharge ducts (also called vent ducts) and other com- ponents. A reputable dust collector sup- plier will follow the vent sizing equations in Chapter 8 (Venting of Deflagrations of Dusts and Hybrid Mixtures). They can also supply a calculations sheet that becomes part of the documentation you keep on file to demonstrate your plant’s compliance. A reputable dust collector supplier may also have performance-based solutions for this type equipment, which is also allowed by the NFPA standards.
Should all dust collectors
be installed outdoors?
Obviously, placing dust collectors outdoors is the safest option if they vent away from buildings and populated areas. However, it isn’t always feasible to place them outside. Dust collectors placed indoors must have the appropriate explosion protection system if they will handle any combustible dusts.
Is it safe to recirculate the air
from your dust collector back
into the work environment? Recirculating heated or cooled air back
into the workspace can provide significant energy savings and eliminate the cost to replace that conditioned air. Containing the air indoors also avoids the time-con- suming permitting involved when con- taminated air is exhausted outside. This can be safely done even if the facility han- dles explosive dust by outfitting the dust collector with a safety monitoring filter. This helps isolate the downstream equip- ment from the progression of a flame front during an explosion.
Brian Richardson, Technical Departments
Manager, has been with Camfil Air Pollution Control since 2008 and has worked in and around manufacturing facilities for almost 25 years. He started as a Research and De- velopment engineer and progressed through various management positions where he was tasked with trouble shooting and servicing dust collectors and training personnel on the maintenance and construction aspects of the equipment. In his current role, Brian liaison between the manufacturing areas, sales and engineering departments and helps manage the company’s maintenance and local com- munity training programs.
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WE’RE ALL IN THIS TOGETHER: ENSURING HEALTH & SAFETY IS OUR MISSION
“Certain critical infrastructure industries have a special responsibility in these times to continue operations.”
– Guidance on the Essential Critical Workforce, DHS/CISA, 3/28/20
AIR SAMPLING
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SOUND & VIBRATION
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FIXED GAS
TRANSMITTERS, SYSTEMS, and SENSORS
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Making the Best Sense since 1983. +1 727-530-3602 Sensidyne.com 800-451-9444
Circle 18 on card. 35