Chemical Hazards at Aquatic Facilities Expert Overview

Aquatic facilities utilize various hazardous chemicals to maintain water safety. When used properly, the public tends not to pay attention; however, missteps in facility operations can lead to toxic chemical inhalation, chemical burns, pathogen exposures, and other serious consequences.

In this article, aquatic safety expert, Maria Bella discusses chemical hazards at aquatic facilities and the standard of care for water treatment at pools, water parks, and other aquatic venues.

Pool Chemical Hazard Expert Witness

Chemical Hazards at Aquatic Facilities – Expert Overview

When the 1996 Summer Olympics were held in Atlanta, Georgia, the FBI prohibited swimming pool contractors from using common chemicals—chlorine and acid—to sanitize the pool water. The FBI didn’t want terrorists to have easy access to ingredients used to produce deadly chemical gas. Decades later, those same chemicals are being used at local pools; handled and dispensed by pool operators that can range from teenagers to adults that may or may not have any professional training.

Preventing chemical gassing incidents at aquatic facilities is achievable when owners focus on properly configuring chemical treatment systems and ensuring that staff are adequately trained in testing and maintenance procedures. Unfortunately, failure to follow proper protocol can cause serious injury or death.

2014: 26 people hospitalized after being exposed to chlorine gas at a waterpark in Michigan.
2015: 34 children exposed to a mixture of sodium hypochlorite (liquid chlorine) and muriatic acid.
2018: 19 people hospitalized after chemical exposure at a swim school.
2018: 22 people exposed to chlorine gas at Disneyland Paris hotel swimming pool.
2020: 23 people suffered chemical exposure at community pool in New Jersey.
2021: 20 people exposed to chlorine gas at Tennessee waterpark.
2021: 21 children transported to hospital after pool chemical exposure in Wisconsin.
2021: 60 people suffered toxic chemical exposure at a Texas waterpark.

Per the CDC:

Toxic chlorine gas releases at public aquatic venues can be prevented by regular testing of chemical control failsafe features, proper training of aquatic facility staff members, and by following standardized policies and procedures, including evacuating bathers from the pool before a recirculation pump is restarted.

Owners and operators of swimming pools have multiple avenues for education on this topic. They may rely on training from the companies who install chemical treatment systems, safety literature from manufacturers of chemical equipment, and Aquatic Facility Operator certification courses offered through the National Recreation and Park Association, as well as the Certified Pool Operator program offered through the Pool & Hot Tub Alliance.

But knowledge is just the first step in preventing chemical incidents at aquatic venues. Proper action, which includes regular monitoring and/or testing of the chemical feed system flow switch, along with ensuring that all mechanical interlocks are properly installed and properly working, should be part of regular operating practice at aquatic facilities.

Monitoring, Testing, and Maintenance of Pool Systems & Equipment

When water treatment is outsourced to a third party, such as a pool management company, it is important to ensure that the contractor installs all necessary fail-safe equipment for the chemical feed system. Their staff must be adequately trained to monitor and test safety interlocks, and to perform regular inspections of the other components of the circulation system that can interfere with proper dosing and distribution of hazardous chemicals.

Regular maintenance must be scheduled so that pumps that circulate water through aquatic attractions (e.g. swimming pool, hot tub, lazy river, etc.) are not manually shut down and restarted when patrons are present. When an unplanned shut down occurs, typically due to a power outage, patrons should be evacuated from the aquatic facility until all components of the circulation system can be safely brought back online and chemical tests have been performed to ensure the facility is safe to re-enter.

Like everything else, chemical equipment degrades over time and must be periodically repaired or replaced. Failing to have a reliable preventive maintenance program established, with calendared equipment rehab or replacement dates, violates the standard of care for the safe operation of a pool, and can result in serious injuries. Further, replacing circulation system components with off-the-shelf rather than OEM parts can lead to failure of the entire system and result in severe, life threatening events for patrons and staff.

Pool Chemical Safety Protocols

In addition to mechanical system failure, basic human error can also create the dangerous conditions the FBI intended to prevent at the 1996 Olympics held in Atlanta. For a distracted delivery driver or onsite employee trying to keep up with excess workload, refilling the wrong vat with a non-compatible chemical when chemical containers aren’t properly marked is easy to do and can quickly lead to disaster. Industry standards require that chemical containers are properly labeled and display readily visible warnings, and some codes even require that incompatible chemicals be stored in separate, locked rooms.

Failing to follow applicable codes and/or standards of care practically ensures a chemical incident will occur. For this reason, thorough training is required for anyone tasked with handling, storing, or transporting hazardous chemicals, and why some states require that training be repeated on a regular basis.

Discovery Considerations for Chemical Exposure/water Treatment Cases

  • Review training history and qualifications of facility operator(s).
  • Review policies and procedures for water treatment and chemical handling.
  • Review policies and procedures for restarting of circulation pumps and water testing.
  • Review policies and procedures and training programs for 3rd party providers.
  • Were incompatible chemicals stored in separate rooms?
  • Were chemicals clearly labelled?
  • Review Emergency Action Plan as it relates to chemical storage and exposures.
  • Review maintenance history of water & chemical systems.
  • Review pool/spa daily chemical test log.

Aquatics Operations Investigations

Maria Bella is an instructor for state-required chemical safety courses and an authorized Aquatic Facility Operator and Certified Pool Operator instructor who has taught thousands of pool owners and operators how to ensure their facilities comply with safety protocol. She worked as a pool operator for more than three decades, ensuring that patrons and staff would not be exposed to toxic chemicals or deadly gas due to mechanical malfunction or human error.

For more information, contact the author or submit an inquiry.

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