There is a lot of confusion on reclassifying Permit-Required Confined Spaces to Non-Permit Spaces, which is allowed on spaces with NO KNOWN or POTENTIAL hazardous atmospheres. 1910.146(c)(7) covers this practice. The key DIFFERENCE between “reclassifying” a space using section (c)(7) and using “alternative entry methods,” which is covered under section (c)(5) is ELIMINATION vs. CONTROL.
(c)(7) REQUIRES ELIMINATION of ALL PRCS hazards, and (c)(5) states you can CONTROL the hazardous atmosphere with FORCED AIR VENTILATION as long as you can show the forced-air blower can maintain a safe atmosphere.
So, how does OSHA consider when a PRCS hazard has been ELIMINATED?
