Pool Chemical Safety

Pool chemicals, such as chlorine and bromine, are added to treated venues (for example, pools, hot tubs/spas, and water playgrounds) to protect swimmers from the spread of germs and prevent outbreaks. Other pool chemicals help with the disinfection process (for example, pH control), improve water quality, stop corrosion and scaling of equipment, and protect against algal growth. However, pool chemicals can injure people when mixed together or when appropriate personal protective equipment is not used when handling them.

Follow these recommendations to prevent pool chemical injuries:

Design of Pool Chemical Storage Area and Pump Room

  • Construction
    • Include spill containment features, also known as secondary containment, in chemical storage areas to prevent pool chemical leaks or spills from mixing with any other substances.
    • Provide aquatics staff and patrons with easily accessible safety showers, eye wash stations, and other appropriate chemical safety equipment.
    • Install appropriate fire suppression equipment.
      • Consult with your local fire department or code enforcement agency for guidance.
    • Provide adequate lighting for reading labels on containers throughout the chemical storage area and pump room.
  • Air handling (for indoor venues)
    • Follow local building codes or American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard External.
      • Separate the air handling systems for the chemical storage area, pump room, and venue area from the rest of the building.
      • If an older building does not have separate air handling systems, consider installing emergency heating, ventilating, and air conditioning (HVAC) cutoffs in these areas.
    • Ensure that the chemical storage area, pump room, and venue area are well-ventilated.
  • Engineering
    • Install an alarm to alert the aquatics staff if the recirculation pump shuts down.
    • Install a device that automatically deactivates the chlorine/pH feed pumps when there is no or low flow in the recirculation system.
  • Security
    • Secure the chemical storage area and pump room to limit access, especially to children and animals.
    • Provide locking mechanisms for the chemical controller to prevent unauthorized tampering.
  • Personal protective equipment (PPE) and safety data sheets (SDSs)
    • Ensure availability of and easy access to PPE and up-to-date SDSs near (for example, in the hallway just outside of) the chemical storage area, pump room, venue area, and any other location pool chemicals are stored or used.
      • Ensure availability of and easy access to PPE and up-to-date SDSs at a location other than those listed above in case of chemical spill or incident that would prevent access.

Chemical Storage

  • Store pool chemicals in compliance with local or state building and fire codes.
  • Store pool chemicals below 95°F/35°C and in conditions recommended by the manufacturer (for example, low humidity and out of direct sunlight).
  • Protect stored pool chemicals from getting wet.
  • Protect individual stored chemicals from mixing together or with other substances by storing each pool chemical separately in a dedicated location and storing incompatible chemicals away from each other.
  • Store chemicals in original, manufacturer’s-labeled containers.
    • Consult with the chemical manufacturer if the container is damaged.
    • Dispose of deteriorating, unwanted, or unlabeled pool chemicals safely.
      • Contact the product’s manufacturer or the local or state hazardous materials group for proper disposal procedures.
  • Protect pool chemicals from heat sources and flames.
    • Do not store possible ignition sources, particularly gasoline-, diesel-, or gas-powered equipment  in the chemical storage area or pump room.
    • Do not smoke in the chemical storage area or pump room.
  • Prioritize good housekeeping in the chemical storage area and pump room. Do not allow rags, trash, debris, etc. to collect in the area.
  • Store and consume food and drinks away from pool chemicals.

Chemical Handling

  • Only allow those who have been trained in pool chemical safety practices to handle pool chemicals.
  • Maintain good communication among pool chemical handlers, including establishing a chain of command and documenting chemical use.
  • Post instructions on pool chemical safety practices in the chemical storage area and pump room. Order laminated posters for FREE.
  • Respond to pool chemical spills immediately by following the emergency response plan and using separate dedicated materials to clean up spills.

Maintenance and Repair

  • Close the venue to swimmers if the recirculation system is not running or before servicing chlorine/pH control feed or recirculation system. Do not allow swimmers back into the venue until after the chlorine/pH control feed and recirculation systems are restarted and run for a minimum of 5 minutes (if water quality meets required standards).
  • Turn off both the chlorine/pH control feed and recirculation systems before servicing either system.
  • Ensure adequate ventilation in and around the pump room and venue area during maintenance and repair and use appropriate PPE.
  • Ensure that only properly trained people service chlorine/pH control feed and recirculation systems.
    • Develop and follow protocols for the maintenance of the chlorine/pH control feed system that will prevent mixing of different pool chemicals, for example flushing water through the chlorine feed tubing before cleaning it with acid.
  • Communicate clearly to other staff about and document maintenance and repairs.
  • Set up a preventive maintenance program and regularly replace equipment or parts before they fail (for example, check for leaks in feed pump tubing, replace tubing regularly, check clamps, and check valves).

Pool Chemical Training for Staff

  • Train all staff in pool chemical safety basics and provide additional training for those working directly with chemicals.
  • Include at least the following topics in operator training/certification to decrease the likelihood of pool chemical injuries:
    • Impact of each pool chemical on the water’s chemistry and the monitoring systems
      • If the test kit’s limit is exceeded, how to measure higher chlorine levels (for example, using dilution or higher range test strips)
    • Layout of a safe chemical storage area and pump room
    • Calculation of venue volume and the appropriate amount of chemicals needed for the volume
    • Safe chemical storage and handling practices (for example, prevent chemicals from mixing together)
    • Basics of preventive and safe maintenance of equipment (for example, close venue to swimmers if recirculation system not running)
    • First aid for pool chemical exposures and other emergency response basics

Emergency Response Plan

Before an incident

  • Develop an emergency response plan which includes:
    • Spill-cleanup procedure
    • Chemical incident and exposure response
    • Clear chain of command and alternates with contact information
    • Evacuation plan
    • Communication plan for alerting patrons, staff, and emergency responders
  • Train the aquatics staff on the procedures in the emergency response plan.
    • Keep a copy of the emergency response plan near (for example, in the hallway just outside of) the chemical storage area, pump room, and venue area and ensure that another copy is also available at a remote location in case of an evacuation.
    • Ensure up-to-date SDSs are easily accessible to first responders in case of evacuation.
  • Have a phone with updated emergency numbers near (for example, in the hallway just outside of) the chemical storage area, pump room, and venue area and ensure that a phone is also available at a remote location in case of an evacuation.
  • Practice emergency response with first responders.

During an incident

  • Activate emergency response plan.
    • For indoor venues, if chemical fumes are released in the chemical storage area, pump room, or venue area and the corresponding air handling system is
      • Separate from other areas of the building, leave HVAC system on to ventilate.
      • Shared with other areas of the building, turn off the HVAC system immediately.

After an incident

  • Document the incident and response and report them to local or state permitting officials. [Local or state permitting officials should consider revising public health regulations in response to reports of pool chemical injuries to reduce the future likelihood of such events.]
  • Conduct a post-incident critique with all parties involved in the response.
    • Revise the emergency response plan as needed.

Chemical Packaging and Labeling (for Manufacturers)

  • Package and label each pool chemical (for example, chlorine and acid) so that they can be easily identified and distinguished from each other.
    • This should be done consistently, as changing the shape, size, or color of the container or labeling can lead to chemical-mixing errors.
  • Notify customers of any changes in the packaging or labeling of pool chemicals.
  • Consider identifying pool chemicals on the container lids.
  • Use labels resistant to both corrosion and deterioration.