The U.S. Centers for Disease Control and Prevention (CDC) has officially released the fifth edition of the Model Aquatic Health Code (MAHC), providing updated guidance for enhancing safety in aquatic facilities. This comprehensive resource is designed to promote safer and healthier experiences at aquatic venues across the country.
First established in the summer of 2014 by the U.S. Centers for Disease Control & Prevention (CDC), the Model Aquatic Health Code (MAHC) aims to help state and local governments develop and update their pool codes based on up-to-date science and best practices. While no agency is required to follow the code by law, it provides a model by which they can build their own, or agencies can simply adopt the standardized guidance of the MAHC.
The code is updated on a regular basis in order to ensure it is recommending the most current best practices, including the most recent science, and incorporating the most updated knowledge of aquatic operations. The Council for the Model Aquatic Health Code (CMAHC), created in 2013, acts as a clearinghouse for input and advice. CMAHC members take part in the process of updating the code and their input is considered as the CDC revises and releases the next edition.
Key Changes Found in the 2024 MAHC (this short list is a high-level summary only).
Chapters 1–3
Established definition for single pass splash pads, eliminated references to foreign standards, removed references to outdated CPSC standard.
Chapter 4
Portable slides are prohibited, as their location is not fixed and the water depth, landing area, and clear spaces are not ensured (MAHC Section, 4.12.2.9.1). A clock must now be visible to all spa bathers (4.12.1.12). Single pass splash pads included as an interactive water play aquatic venue and subject to applicable MAHC design standards and construction (4.12.8), and facility operation and maintenance requirements (5.12.8).
Chapter 5
CDC accepted a CMAHC rejected change request that specified the upper operating range for chlorine products is dictated by the manufacturer’s instructions for use, in compliance with the EPA’s Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (5.7.3.1.1.5). Cyanuric acid (CYA) at 300 ppm or higher now requires immediate remediation (5.7.3.1.3.3).
Chapter 6
The aquatic venue diarrheal-stool contamination response in the presence of CYA was modified to add dilution credits when draining and refilling to lower the CYA concentration (6.5.3.2.1). A table was also added to display log reductions based on the initial CYA concentration and the percentage of the aquatic venue drained and refilled. Three additional health hazards were added requiring immediate closure (6.6.3.1). Failure to provide interlock controls and flow meters/flow switches/pressure switches in accordance with section 4.7.3.2.1.3, or they are not operating properly, or have been disabled or bypassed. Failure to prevent unauthorized access to pool chemical storage spaces. Free chlorine greater than 10 ppm while bathers are present. Two qualified lifeguards are required to be present and available to respond to aquatic emergencies in aquatic facilities that have a single zone of patron surveillance (6.3.4.3.1).
Chapter 7
Artificial swimming lagoons (ASLs) design standards and construction, and operation and maintenance requirements now included as a special venue (7.3 & 7.4).
The MAHC continues to provide comprehensive guidance for facility operators, health officials, and stakeholders. The MAHC is available online and free to access. Aquatic facility operators are encouraged to review the new guidance and implement these measures to support public health.
View the 2024 MAHC Here: https://www.cdc.gov/model-aquatic-health-code/php/our-work/index.html