35 Swimmers In San Jose Treated For Chemical Exposure

35 swimmers were treated for chemical exposure last Thursday, June 14th, as a pool attendant working at Shadow Brook Swim Club in San Jose, California reportedly poured the wrong type of chemicals into the facility’s pool tanks.

With a yellow gas cloud seeping onto the pool deck, the affected swimmers were vomiting, having shortness of breath and experiencing dizziness when the San Jose Fire Department arrived on the scene.

The affected persons were transported to nine different hospitals after ‘getting stripped of their clothes and rinsed with water.’ San Jose authorities say that those affected could have ‘potentially drowned from fluid buildup in their lungs’ if they had been left untreated.

Per SF Gate, officials measured 15ppm of chlorine in the pool tank room later that Thursday and it remained unclear how It is unclear how long it would take for officials to get chlorine levels back to safe levels.

Below is a tweet from a local reporter from Thursday evening, detailing the situation at the time.

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2 years ago

Chlorine gas was one of the chemical weapons used during trench warfare in WW1.

Sum Ting Wong
Reply to  KeithM
2 years ago

A 2 edge sword . Chlorine can have some bad effects esp in trenches as it sinks . I expect it was used to flush out trench occupants . It is said to be dropped by something called barrel bombs but unless the barrel hits you on the head , it won’t kill you . It is easily escapable but you may have some sore nose throat & oesophagus linings & weeping eyes . The other side is that it has sanitised water . Also If the soldiers returned to their trenches ( & they did if not shot ) , they would find them in a much better state bacteria wise . So on the whole a very big… Read more »

Jay ryan
Reply to  Sum Ting Wong
2 years ago

Just to be clear Cl2 gas can DEFINITELY kill you, often with acute pulmonary edema and ARDS.


When I was a pool lifeguard in the 1970’s we were tasked with changing the Chlorine tanks in the pump room. Big tanks of chlorine gas moved by hand and bolted onto the regulators with wrenches. No special training, no lung or eye protection, no security or locks in the pump room. We are lucky we didn’t kill each other and everyone else in the area.

Thanks for the history lesson though, Sum Ting Wong, and say hi to the rest of your Asiana Flight crew.


2 years ago

For reference, competition pools are typically around 2 ppm of chlorine, and anything above 4 ppm is a hazard for skin and eye irritation.

2 years ago

Cyanogen Chloride is also classified as a chemical warfare agent that was also used in WWI. This occurs when swimmers pee in the pool, and the urine reacts with Chlorine. It was so bad at my daughter’s last state championship swim meet, that she skipped some finals, and other swimmers ended up in the ER. Our LSC is very aware of it, and seemly doing nothing about it.

About Retta Race

Retta Race

After 16 years at a Fortune 1000 financial company, long-time swimmer Retta Race decided to change lanes and pursue her sporting passion. She currently is Coach for the Northern KY Swordfish Masters, a team she started up in December 2013, while also offering private coaching. Retta is also an MBA …

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