Swimming Pool Chemicals: Guidelines For Adjusting Chemical Levels

In 2008, a homeowner in Suffolk County dumped five one-pound bags of pool shock into his pool chlorinator. His actions produced chlorine gas and an explosion. The police, fire department and emergency medical services responded. The resident was decontaminated at the scene and then transported to the hospital. He was admitted to the hospital with severe burns to his face, respiratory irritation, central nervous system and heart problems.


Know your pool chemical levels before making an adjustment.
Test your water with strips or chemical kits that are not expired.
Adjust pool chemistry with products that are not expired.
Read and follow label instructions.
Keep pool chemicals out of reach of children.
Use a clean scoop or dipper.
Add acid to water, not the reverse.
Dissolve powders/crystals in water before adding to pool water.
Follow protective measures, such as wearing appropriate personal protective equipment.


Use same scoop for different pool chemicals.
Mix chemicals.
Pour chemicals into the swimming pool while people are in the water.

For Additional Information

Send your questions and comments to ntsip@health.state.ny.us, or contact staff at National Toxic Substance Incidents Program:

Center for Environmental Health
Bureau of Toxic Substance Assessment
Empire State Plaza-Corning Tower, Room 1743
Albany, New York 12237
Phone: (518) 402-7810
Fax: (518) 402-7819

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