Confined space – is a space defined by the existence of ALL of the following conditions:
1. Large enough and so configured that an employee can physically enter and perform assigned work; and
2. Limited OR restricted means for entry or exit; and
3. Not designed for continuous employee occupancy.
Permit-Required Confined Space - A confined space that has, in addition to the three conditions above, 1 or MORE of the following characteristics:
1. Contains or has a known potential to contain a hazardous atmosphere;
2. Contains a material with the potential for engulfment of an entrant;
3. Has an internal configuration such that and entrant could be trapped or asphyxiated by inwardly converging walls or a floor which sloped downward and tapers to a small cross-section; OR
4. Contains recognized serious safety or health hazards.
Potential confined spaces need to be evaluated & labeled with a sign if reqd. Some confined spaces do not allow for a sign. For example, sewer & storm drains entered through manholes are to be considered permit required confined spaces, whether labeled or not. Employees must not rely solely on a warning sign. Employees must be trained by supervisors to recognize areas that may be confined spaces – and not enter these areas until a determination is made.