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Model Aquatic Health Code (MAHC) Drafts

NOTICE: This web page was archived for historical purposes once the MAHC was completed. The content is no longer maintained and might be out of date. For current information about the Model Aquatic Health Code, visit the Model Aquatic Health Code homepage.

This page includes first and second drafts of each MAHC module, the MAHC "Knitted" version, changes made to it that resulted in the 2014 MAHC (1st Edition), all public comments and responses from the public comment periods, and all module abstracts.

MAHC "Knitted" Version, Public Comments, and Responses

Public Comments and Responses From the 2nd 60-Day Public Comment Period

Posted 08/29/2014.

The attached document lists all public comments and responses received during the second 60-day public comment period ordered by MAHC section number. During the second 60-day public comment period for the MAHC "Knitted" version, CDC received 1,428 comments. The MAHC agreed with or made changes based on 839 (59%) comments and disagreed with 482 (34%); 107 (7%) comments were without suggestion or partially accepted with no changes made. Of comments that the MAHC could accept or reject (1,321), the MAHC agreed with and incorporated 64% of the suggestions.

MAHC "Knitted" Version

Posted 09/12/2014 after addressing the second round of public comments. These documents tracks all changes made in the MAHC "Knitted" version Code and Annex in response to the second round of public comments. Acceptance of these changes resulted in the MAHC 1st Edition.

Posted for second and final 60-day public comment period on 03/28/2014. Closed for public comment 05/27/2014.

Note: This MAHC "Knitted" version is historical in nature and does not reflect current MAHC wording.

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Module Drafts, Public Comments, and Responses

Public Comments and Responses From the First 60-Day Public Comment Period

Posted 04/03/2014.

The attached documents list all public comments and responses received during the first 60-day public comment period in MAHC section order either by the section number used in the module as originally posted or by the section number found in the complete MAHC "Knitted" version after the modules were merged into a single document and section numbers were adjusted as needed. During the first 60-day public comment periods for all modules, CDC received 2979 comments. The MAHC agreed with or made changes based upon 1904 (64%) of comments and disagreed with 600 (20%); 475 (16%) comments were neutral or required clarification. Of comments that the MAHC could accept or reject, the MAHC agreed with and incorporated 76% of the suggestions.

Recirculation Systems and Filtration

Lifeguarding and Bather Supervision

Ventilation and Air Quality

Disinfection and Water Quality

Regulatory (Formerly known as the Regulatory Program Administration)

Facility Design and Construction

Risk Management/Safety

Facility Maintenance and Operation

Monitoring and Testing

Contamination Burden

Posted 06/05/2013 after addressing public comments.

Posted for 1st 60-day public comment period on 07/20/2012. Closed for public comment 10/14/2012.

Hygiene Facilities

Fecal/Vomit/Blood Contamination Response

Operator Training

Preface, User Guide, Definitions


Recirculation Systems and Filtration Abstract

Health issues related to waterborne diseases as well as exposure to chemicals associated with pool water are increasingly being documented. The Recirculation Systems and Filtration Module is a first step towards improving water quality at aquatic facilities and reducing associated health effects. The Recirculation Systems and Filtration Module contains design and construction requirements that are, unless otherwise specified, applicable only for new or substantially altered construction. New and improved elements include:

  • More aggressive turnover times and more uniform standards for recirculation system design and operation.
  • Filter design and operation standards that will promote more effective and efficient filtration.
  • Requiring water replenishment to dilute out the dissolved contaminants that cannot be removed by pool filters.
  • Development of a long-term plan to use pool filters for pathogen removal in addition to water clarity in a multiple barrier system that would complement all disinfection processes.
  • Use of improved flow meters

Contamination Burden Abstract

Understanding the types of contaminants and the magnitude of disinfectant demand by various environmental factors (e.g., particulate) is an essential component to design and operate a recirculation and filtration system. Limited data currently exists, but a substantial research agenda has been created.

The following is a summary of the existing data and areas where data are lacking. Since the Contamination Burden Module is informational, this module is ANNEX-based only – NO CODE section accompanies it. After being posted for public comment, the information contained in this module will be merged into the appropriate MAHC modules upon final completion. The section numbering system will be different in this draft as there are no specific code sections yet assigned to any of this information.

Disinfection and Water Quality Abstract

Disinfection and water quality are critical components in maintaining bather health and comfort. Health issues related to inadequate disinfection and poor water quality are increasingly being documented. Outbreak investigations have often determined that disinfectant levels and other water quality parameters were not maintained appropriately thereby allowing disinfectant-sensitive pathogens to be associated with pool use. The emergence of chlorine-tolerant microbes also necessitates changing accepted standards for pool treatment to protect the health of bathers in the future. The Disinfection and Water Quality Module takes the first steps in addressing these recurring and emerging aquatic health issues. The Disinfection and Water Quality Module contains requirements for new or substantially altered construction that include:

  • Primary disinfectant levels set.
  • Secondary disinfection required for "increased risk" aquatic venues such as Interactive features, spray pads, wading pools, and other venues designed primarily for diaper-aged children as well as therapy pools
  • Combined chlorine maximum levels set
  • Prohibition of cyanuric acid in some "increased risk" aquatic venues

Facility Design and Construction Abstract

The sound design and construction of swimming pools, spas, and aquatic venues are paramount to ensuring the health and safety of patrons who use these facilities. The Facility Design and Construction Module contains requirements for new or substantially altered pool construction that includes:

  • Design/construction aspects of the pool shell that include general shape, design, and slope requirements to prevent injury;
  • Design/construction aspects of the aquatic venue that include decks, lighting, electrical, wastewater, and fencing;
  • Design/construction aspects of specialty bodies of water and features that include spas, wave pools, slide pools, wading pools, and infinity edges; and
  • Design/construction parameters for pool equipment and under what conditions its use is acceptable including starting blocks, moveable floors, bulkheads, and diving boards.

Facility Maintenance and Operation Abstract

Aquatic facility operation and maintenance is a critical component of maintaining health and safety. Past outbreaks have commonly found operation and maintenance lapses to be critical contributors to disease outbreaks and injuries. The Facility Maintenance and Operation Module lays the foundation for operational improvement by containing requirements for:

  • Closure and reopening guidance for long and short term closures
  • Comprehensive plans for preventive maintenance, equipment inventorying, and development of an operations manual to be maintained at the facility
  • Reducing and mitigating excessive glare and reflection on the pool surface through design and adjustments to windows and lighting equipment
  • Comprehensive daily records of pool operation and maintenance and of operational items inspected daily

Hygiene Facilities Abstract

Swimmer hygiene is a critical component that plays a role in documented waterborne disease outbreaks and poor water quality. The Hygiene Facilities Module is a first step towards improving swimmer hygiene and facility water quality to reduce the associated health effects. The Hygiene Facilities Module contains requirements for new or substantially altered construction that include:

  • Minimum distances for hygiene facilities from aquatic venues
  • Newly defined diaper changing stations
  • Implementation of rinse vs. cleansing showers

Lifeguarding and Bather Supervision Abstract

Health and safety issues related to bather supervision and lifeguarding for both the patron and the potential rescuer at an aquatic facility are increasingly being documented. The Lifeguarding and Bather Supervision Module is a first step towards improving the consistency in training, lifeguard management and supervision, lifeguard competency for guarded facilities and effective bather supervision at unguarded facilities.  The Lifeguarding and Bather Supervision Module contains requirements for unguarded and guarded aquatics along with the training necessary to be a qualified lifeguard. The module includes:

  • Standards determining which aquatic facilities need to be guarded and which may not need qualified lifeguards including supervision requirements for those aquatic facilities not required to have lifeguards.
  • A Safety Plan guide including pre-service, in-service, staffing, single lifeguard, lifeguard management and Emergency Action Plan requirements.
  • Requirements for aquatic facilities to define, diagram, and document required zones of patron surveillance.
  • Determination of what constitutes effective staffing by the ability of the lifeguard to reach all areas of their zone of patron surveillance within a certain time frame.
  • Required lifesaving equipment, communications standards, and general requirements for lifeguards and lifeguard supervision/management training.

Monitoring and Testing Abstract

Ensuring water and air quality is important for maintaining a safe and healthy environment for pool and spa users and operators. The Monitoring and Testing Module identifies activities and procedures that pool and spa operators should follow to proactively evaluate the water and air quality in their facilities. The Monitoring and Testing Module contains requirements for new and existing aquatics facilities that include:

  • Ensuring that water quality testing devices comply with existing standards.
  • Requiring automatic controllers
  • Monitoring automated controllers and treatment systems to ensure proper functioning.
  • Use of dye testing to evaluate pool circulation.
  • Procedures for collecting water samples from in-line sample ports and from bulk pool water, including frequency and timing of sample collection.
  • Frequency of testing for specific water quality chemical parameters.

Operator Training Abstract

Increased pool code violations have been linked to the lack pool operator training. These violations may also be linked to an increased potential for health effects if a facility is not operated and maintained appropriately. The Operator Training Module is a first step towards assuring adequate training for all personnel who operate aquatic facilities. The Operator Training Module contains requirements for:

  • Training course elements to be included in curricula
  • Instructor qualifications
  • Certificate validity to be for 5 years maximum

To make the module more complete and interpretable, proposed language from the Regulatory Program Administration Module is also included (, This language outlines the requirement for operator training and the aquatic facilities requiring on-site qualified operators.

Regulatory Abstract

Regulatory guidance forms the framework around which an effective model aquatic health code is built. The Regulatory Module follows a best practice and research-based protocol to ensure the AQUATIC FACILITY is operating safely. The guidance reflected in this module promotes all parties working together from the initial building permits to the code enforcement process. The Regulatory Module contains requirements for but not limited to:

  • Plans and permits guidelines
  • Delineation of imminent aquatic health hazards and corresponding remediation and enforcement procedures.
  • Establishment of facility staffing requirements based on facility size and type.
  • Recordkeeping requirements

Risk Management/Safety Abstract

Increased vigilance is needed at aquatic venues to reduce injuries in the water, chemical storage room, and around the pool and facility. The Risk Management/Safety Module outlines steps to be taken to manage and reduce these risks and associated health problems. The Risk Management/Safety Module contains new guidelines covering:

  • Controlled access aquatic venues (e.g., lazy rivers) not requiring depth markers throughout
  • Expanded employee training to cover fecal- and vomit-related pathogen response and clean-up
  • Potential sources of glare and ways to prevent glare in aquatic venue design
  • Consideration of water temperature and patron use
  • Expanded chemical storage and handling
  • Use of remote monitoring systems
  • Employee illness policies
  • Inspection items for daily opening and closing of aquatic features or venues

Ventilation and Air Quality Abstract

Health issues related to indoor pool use and associated poor water and air quality are increasingly being documented. The Ventilation and Air Quality Module is a first step towards improving air quality at indoor aquatic facilities and reducing associated health effects. The Ventilation and Air Quality Module contains requirements for new or substantially altered construction that include:

  • Reliance on ASHRAE 62.1 for determining the amount of outdoor air required.
  • Discussion in the Appendix of an alternative way to determine the extra make-up air needed based on the indoor venue water use type (e.g., flat water, agitated water, or hot water) and venue or deck patron density (square feet/person).
  • Outlining of air handling system performance criteria.
  • Outlining of operator maintenance, recordkeeping, and operational requirements.
  • Development and implementation of plans to reduce combined chlorine compounds in indoor aquatic facilities and inform facility patrons of their impact on building air quality.

Fecal/Blood/Vomit Contamination Response Abstract

Health issues related to fecal contamination of aquatic facilities are well documented. The Fecal/Vomit./Blood Contamination Module contains requirements for planning, training, and response to contamination of aquatic facility water and surfaces by these biological fluids that include:

  • Response plans for vomit and formed or diarrheal stool contamination events.
  • Response plans for contamination of surfaces with blood.
  • Requirements for training in the fecal/vomit/blood contamination response plans.

Preface/User Guide/Glossary Abstract

The Preface/ User Guide / Glossary Module outlines the rationale, history, and impetus for creation of the MAHC and its sponsorship by CDC. Infectious disease outbreak and injury data, and the lack of a national model support creation of the MAHC. The module explains the operating premises that served as the foundation for creation of the MAHC and outlines long term plans for updating it to ensure it remains current. This is followed by a User Guide that explains how the MAHC should be read, interpreted, and implemented. A partial Glossary is included that defines specific terms. When all MAHC modules are combined into a single MAHC document, the MAHC will include a complete Glossary that includes all terms defined across all modules within the MAHC. The MAHC will:

  • Ensure the best available standards and practices for protecting public health are available.
  • Incorporate data and best-practices based practices.
  • Updated on a regular basis with wide input.
  • Serve as a model that can then be used by state and local public health agencies to adopt in part or in full as regulations for their jurisdiction.