What specific fluid checks must be performed on a potable water truck before servicing an aircraft, to prevent contamination?

Before servicing an aircraft with potable water, specific fluid checks must be performed on the potable water truck to prevent contamination. The most crucial check is to verify the chlorine level in the water. Chlorine is a disinfectant that kills bacteria and other harmful microorganisms. The chlorine level should be within the range specified by health regulations, typically between 0.2 and 2.0 parts per million (ppm). A chlorine test kit should be used to measure the chlorine level. A visual inspection of the water tank is also essential. Check for any signs of sediment, discoloration, or other foreign matter. If the water appears to be contaminated, it should not be used. Inspect the water hoses and nozzles for cleanliness and integrity. Ensure that they are free of cracks, leaks, and other damage. Disinfect the hoses and nozzles before each use. Check the truck's water filter to ensure that it is clean and properly functioning. A clogged or damaged filter can compromise the quality of the water. Verify that the truck's water tank is properly sealed to prevent contamination. The tank should be equipped with a secure lid and vent. Check the truck's backflow preventer to ensure that it is functioning properly. A backflow preventer prevents water from flowing back into the truck's water tank from the aircraft's water system. Review the truck's maintenance records to ensure that all required maintenance and inspections have been performed. The records should document the date of the last tank cleaning, filter replacement, and backflow preventer testing. Only potable water that meets or exceeds regulatory standards should be used to service aircraft. Non-potable water poses a serious health risk to passengers and crew. All checks should be documented on a checklist to ensure that no steps are missed.