False assumptions about hazardous locations can turn them into lethal locations. Let’s review these four dangerous assumptions.
- “If the equipment is on the bill of materials, I can install it here. No problem.” The bill of materials might be wrong. Closely examine every fitting, enclosure, fixture, and other equipment to ensure it meets the listing and marking requirements of the Chapter 5 Article for that particular hazardous location. If it isn’t, don’t install it.
- “Everything’s grounded, so there’s no danger of flashover.” A ground rod does not prevent differences of potential. Only bonding does this. Incorrect measurement techniques can also cause flash (e.g., always connect your meter one lead at a time).
- “That brass hammer is necessary only if you’re doing a lot of tapping. I just need to tap that cover off.” Can you say “Kaboom?” It takes only one spark.
- “If I keep this lighter in my pocket, there won’t be any danger of ignition from it.” The lighter is an ignition source. Don’t bring it into the hazardous location.