50 UNLOADING
The tank may be under pressure. Do not open the dome. Do not open any valves. Do not remove couplers or hoses until pressure has been relieved. (see TTMA TB No. 80) Do not load or unload trailer without proper support. The trailer may become unstable and damage may result.
Make sure that the parking brake is set before unloading the equipment.
Make sure that all unloading gear (hoses, couplings, valves, etc.) are compatible with the product that you are unloading.
When discharging, opening manholes or vents of adequate capacity are required before opening the products discharge valve. This will avoid damage due to a vacuum collapse of the tank if pumping off or gravity discharging. This will also prevent the retention of product in the hose resulting in spillage. Drain the hose before disconnecting to avoid spilling product.
Properly connect vapor hoses and open vapor vent before unloading. Failure to properly vent can cause tank collapse during product discharge.
Provide vacuum relief to the tank in the form of vapor recovery, vent valves, or opening a manhole. Failure to relieve the vacuum can cause tank collapse and/or structural damage. Make sure both ends of the discharge line are secure before opening the discharge valve. When opening the discharge valve, crack it slightly to begin with to check for leaks.
Provide proper grounding when unloading using either a pump hose, gravity discharge hose, or vapor recovery hose.
Made with FlippingBook Annual report maker