(1) When internal combustion engines, furnished by you are used in a fixed position below decks, for such purposes as driving pumps, generators, and blowers, the exhaust must be led to the open air, clear of any ventilation intakes and openings through which it might enter the vessel

(2) All exhaust line joints and connections must be checked for tightness immediately upon starting the engine, and any leaks must be corrected at once.

(3) When internal combustion engines on vehicles, such as forklifts and mobile cranes, or on portable equipment such as fans, generators, and pumps exhaust into the atmosphere below decks, the competent person must make tests of the carbon monoxide content of the atmosphere as frequently as conditions require to ensure that dangerous concentrations do not develop. Employees must be removed from the compartment involved when the carbon monoxide concentration exceeds 50 parts per million (0.005%). You must use blowers sufficient in size and number and so arranged as to maintain the concentration below this allowable limit before work is resumed.