Regulations, Safety, and Administration
Regulations, Safety, and Administration ties technical work to legal duties and worker protection. Expect questions on the Safe Drinking Water Act, Clean Water Act, NHDES rules, operator certification, consumer confidence reports, records, and the hazards that injure operators: chlorine, hydrogen sulfide, methane, confined spaces, and excavations.
Regulatory frame
New Hampshire implements the SDWA through RSA 485 and Env-Ws rules, and the CWA through RSA 485-A and NPDES permits. Operators must hold the correct grade and complete continuing education. Community water systems must deliver a Consumer Confidence Report by July 1 each year. Monitoring, discharge monitoring reports, and notices of violation have deadlines; exceeding a limit usually requires NHDES notification, not just a note in the log.
Safety
Chlorine gas is heavier than air and attacks the lungs; use respiratory protection and a chlorine kit, and never enter a leak area without SCBA. Confined spaces require pre-entry testing for oxygen, flammables, and H2S, ventilation, an attendant, and a retrieval system. Trenches 5 ft or deeper need protective systems and a competent person. Lockout/tagout, HazCom labeling, and emergency action plans are inspection targets.
Worked example
A chlorine room is 20 ft × 15 ft × 10 ft = 3,000 ft³. For 12 air changes per hour, airflow = 3,000 × 12 = 36,000 ft³/hr ÷ 60 = 600 cfm. If the fan is rated 400 cfm, the room gets about 8 changes per hour, below the target, so ventilation or the setpoint must change.
Traps
Assuming odor detects chlorine at safe levels, using water on a chlorine container, entering a confined space to rescue without SCBA, and treating the CCR deadline as fiscal-year-end.