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Only licensed plumbers should install and maintain plumbing systems. The greatest challenge to water safety comes from cross-connections. These are physical links through which contaminants from drains and sewers can flow into the potable water supply. Vacuum breakers and air gaps can be used to prevent this backflow problem.


  1. Only use liscensed plumbers
  2. Cross-connections cause many problems
  3. Use air gaps to prevent backflow