A new rule addresses manholes and lift stations, as well as road excavations, drilled shafts in bridges, and water tunnels in dams.
A rule that could be finalized as soon as the next president enters the White House attempts to keep construction workers—as opposed to workers in general industry, for which the Occupational Safety and Health Administration (OSHA) has a standard—safe.
The proposal sets out four types of “confined spaces,” based on potential dangers, and then prescribes safety steps for each. The most regulated (i.e., potentially dangerous) worksite is a Continuous System-Permit-Required Confined Space (CS-PRCS), a designation OSHA developed especially for sewer systems.
“Many contractors who perform construction work in sewer systems are unfamiliar with the hazards associated with these worksites,” the proposed rule states. “Therefore, OSHA placed more emphasis on assessing hazards at sewer worksites than it did in the general industry confined-spaces standard.”
Attendants would have to be posted outside sewer worksites, which would also require monitoring for atmospheric hazards underground and the setting up of an early-warning system to alert attendants that an engulfment hazard may be developing. Early-warning systems include, but are not limited to, alarms activated by remote sensors; and lookouts equipped to immediately communicate with the authorized entrants and attendants.
The next most-dangerous worksite is the Permit-Required Confined Space (PRCS). Attendants would be required, but early-warning systems or atmospheric monitoring would not.
Public agencies must show contractors where confined spaces are, but are not liable for contractor violations.
Also read author Steve Barlas' article on nationwide standardization of traffic control devices and signs, Signs of the Times.