1. Photometers, nephelometers, turbidimeters, interferometers, retractometers, detectors

2. $ Daily inspections performed on the plant should include the following maintenance and inspection procedures: $ Inspect for any security breach - e.g. door unlocked or ajar, window broken $ Ensure heat is on in cold weather $ Check all fittings and piping for leaks $ $ Other maintenance should include: $ Exercise and lubricate valves monthly $ Calibrate flow meters annually $ Clean the turbidimeter and chlorine anlayzer chamber monthly $ Calibrate the turbidimeter quarterly or as recommended by manufacturer.