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August 2016 Edition
Focus Vendor: ChlorKing

Captain Aquatic Opinion of the MAHC Monitoring & Testing Module

As Bobby Darin crooned, “Look out – old MAHCy is back!”

Long time readers will recall that MAHC is the CDC’s ModelAquatic Health Code. Not intended to be law, but likely to be a blueprint for swimming pool regulations throughout the country, the MAHC is constructed of 14 modules currently undergoing review by industry professionals. Since November is compliance month here at Michigan Pool News, we thought we would have Michigan’s moistest superhero and MAHC guru, Captain Aquatic, take a look at the Monitoring and Testing Module.

One glance at this module tells you that the CDC recognizes the global reach of the Ann Arbor-based National Sanitation Foundation (NSF International). The phrase, “Conformity with NSF/ANSI Standard 50 shall be evidenced,” appears throughout the module. So, if anything, it appears the MAHC will only enhance the power of NSF 50.

NSF 50, first published in 1977, is enforced in over half of the states in the country, including Michigan. It sets minimum requirements for materials, design, construction and performance of equipment commonly included in the water circulation systems of swimming pools, spas, and hot tubs. A joint committee consisting of regulatory officials from various U.S. states, industry representatives and product users, reviews and revises the standard every year.

The NSF 50 covers pretty much all pool equipment:

  • Pipe and fittings
  • Materials
  • Suction fittings
  • Filters
  • Pumps
  • Multiport valves
  • Surface skimmers
  • Mechanical chemical feeders
  • Flow-Through chemical feeders
  • Process equipment, which includes ozonators, UV treatment systems, electrolytic chlorinators and brominators (inline and brine tank), and copper/silver ion generators

The takeaway from this portion of the MAHC is to simply make sure your equipment is NSF-certified. NSF has made it easy to check. Just click on over to

This module of the MAHC also focuses on proper inspection of equipment. For example, automated controllers “shall be monitored at the start of an operating day to ensure proper functioning.” This inspection must be done in person using visual observation.

Water testing also gets special attention in this module. Specifically, “Free available chlorine (FAC), combined available chlorine (CAC), or total bromine (TB), and pH shall be tested at all aquatic venues prior to opening each day.” In addition, FAC or TB and pH shall be tested every two hours at all pools using a manual disinfectant feed system and every four hours if using an automatic feed system. How might these regulations be enforced? Most likely, operators would be required to keep a log book of daily tests that a state or municipal official could inspect.

Ozone and UV systems also get a section in this module. Monitoring of these systems is spelled out with specific tests and the frequency of these tests. For example, the power draw of these systems should be recorded every four hours, and the number of cycles per week of the UV lamp must be recorded weekly.

Compliance is clearly an area where the MAHC could show its teeth. (Snap your fingers and sing it like Bobby Darin… “Oh, the shark, babe, has such teeth, dear…”) Be prepared for the daily routine of facility operators to get more complicated in the future.

One Response to “Captain Aquatic Opinion of the MAHC Monitoring & Testing Module”

  1. Gil Daws says:

    In my view,more frequent swimming pool/spa water testing is a necessity and must be promoted.

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