High and low vapor pressure protection for tankships-T/ALL.

§ 39.2013 High and low vapor pressure protection for tankships—T/ALL. Each tankship with a vapor collection system must be fitted with a pressure-sensing device, located as close as practicable to the vessel vapor connection, that measures the pressure in the main vapor collection line, which— (a) Has a pressure indicator located on the tankship where the cargo transfer is controlled; and (b) Has a high-pressure and a low-pressure alarm that— (1) Gives an audible and a visible warning on the vessel where the cargo transfer is controlled; (2) Activates an alarm when the pressure-sensing device measures a high pressure of not more than 90 percent of the lowest pressure relief valve setting in the cargo tank venting system; and (3) Activates an alarm when the pressure-sensing device measures a low pressure of not less than 0.144 pounds per square inch gauge (psig) for an inerted tankship, or the lowest vacuum relief valve setting in the cargo tank venting system for a non-inerted tankship.