If there is any possibility that the trench or excavation could contain a hazardous atmosphere, atmospheric testing must be conducted prior to entry. Testing should be conducted before employees enter the trench and should be done regularly to ensure that the trench remains safe. The frequency of testing should be increased if equipment is operating in the trench. Testing frequency should also be increased if welding, cutting, or burning is done in the trench. Employees required to wear respiratory protection must be trained, fit-tested, and enrolled in a respiratory protection program.
Some trenches qualify as confined spaces.
When this occurs, compliance with OSU's Confined Space Program is also required. Water removal equipment, such as pumps, used and monitored by a competent person. Employees removed from the trench during rainstorms Trenches carefully inspected by a competent person after each rain and before employees are permitted to re-enter the trench. Excavations or trenches 20 feet deep or greater must have a protective system designed by a registered professional engineer. Excavations under the base of footing of a foundation or wall requires a support system designed by a registered professional engineer.