SECTION 15.50 CONFINED SPACES

Last Update: 11/03

This guideline summarizes the requirements of the permit-required confined spaces regulation 29 CFR, 1910.146, which requires employers to protect employees from the hazards of entering confined spaces. Confined spaces are areas that employees can bodily enter to perform work, but has limited means of entry or exit, and are not designed for continuous occupancy. Tanks, sewer pits, boilers, and storage bins are typical examples. Hazards can include explosive, flammable or toxic atmospheres; engulfment; entrapment; electrical, mechanical, or chemical energy; oxygen deficiency; or any combination of hazards. Some confined spaces may become hazardous from natural causes, such as hydrogen sulfide buildup in sewers, or they may become hazardous because of the activity taking place within, such as welding.

All areas of the facility or grounds must be evaluated for the presence of confined spaces, the intended use of the space, and what activities would be expected to take place in the space. In addition, all sources of potentially hazardous conditions in and around the space should be identified. Finally, based on the assessment, a strategy must be developed to determine if it is necessary to enter the space, and if so, under what specific conditions entry should be made. A decision flow chart is provided in Appendix A of 29 CFR 1910.146.

Numerous tunnel systems exist at many state facilities. Some are designed for foot traffic between buildings, while others are primarily for utility access. A general hazard evaluation and ventilation assessment should be conducted and documented. Methods of hazard control will be developed from the evaluation and may include: restricted access, permit-required entry, or mechanical ventilation.