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Post: Blog2_Post

I smell a pool, we don't have a pool...

Updated: Jul 4

It’s 1700 on a Saturday evening, and you’re alerted to a garden-style apartment complex for a “terrible odor” coming from apartment 3C.”

It’s a cool spring afternoon with a light breeze, and as many people are doing, it’s “spring cleaning time.” While enroute to the call, you get an update via 911 that the caller thinks the apartment occupant may have been mixing some household chemicals to make a “stronger” cleaner after watching some TikTok videos. What are some of your thoughts?

When you arrive at the apartment, you are met with the caller who says, “It smells kind of like a pool in here, and we don’t even have a pool in this complex!” While approaching apartment 3C, you notice the faint wisps of a yellowish-greenish vapor coming from under the apartment door. You can hear someone inside coughing loudly.

What do you do next?

  • What are we possibly dealing with, and how did we get here?

  • What are some potential hazards?

  • What can you do to mitigate these hazards?

  • What are the risks to you and your crew?

  • What are the risks to other occupants?

  • What’s next?

What are we dealing with:

So, we’re dealing with an accidental chlorine gas formation by the mixture of household bleach and vinegar. Seems harmless enough, right? But people often think mixing both chemicals, commonly used for cleaning and disinfecting, might be “better” to “get some tough stains out.” I’ve personally seen some “Facebook Reels” and “TikTok” videos of users mixing random chemicals to clean toilets and bathtubs…. I do not recommend mixing chemicals unless they are specifically designed and recommended to be mixed.

Potential Hazards and Medical Implications:

According to the Centers for Disease Control (CDC), Exposure to Chlorine Gas may show the following Signs and symptoms (Centers for Disease Control, 2023)

Hazard Mitigation:

Consider starting a truck or rescue squad company for positive pressure ventilation fans (PPV) for forced air decontamination as soon as possible. Also, start a hazmat company and engine company as quickly as possible.

The primary means of mitigation is removing the victim from the hazardous area. If liquid chlorine is present on the victim, remove the clothing and wash the skin off with mild soap and water.

Medical Treatment:

  • Remove the victim from the environment.

  • Utilize PPV Fans to “blow off” any residual gas on their clothing. Remove any clothing contaminated with liquid chlorine residue. Always protect the patient’s privacy as appropriate.

  • If they are not already there, get ALS-level care to the patient as soon as possible.

Physical exam findings for acute exposures to chlorine (generally > 5 ppm): (Guldner GT, 2023)

  • Tachypnea

  • Cyanosis

  • Wheezes

  • Intercostal retractions

  • Decreased lung sounds

  • Rales, nasal flaring, stridor

  • Hemorrhage in the respiratory tract and rhinorrhea.

  • Clinicians may also find tachycardia, lacrimation, and salivation.


If they have not begun vomiting, Do NOT induce vomiting.

Administer oxygen as needed and monitor breathing with ETCO2 and SpO2.

Be prepared to take an advanced airway early. Monitor the patient for signs of worsening respiratory distress.

Bronchodilators are appropriate for wheezing within your protocols or with OLMC.

There is no known antidote for chlorine poisoning; it is just management for respiratory failure with oxygenation and any chemical burns from liquid spilled on the skin, though chlorine burns are typically only superficial in nature. Further management for long-term effects must be conducted at the hospital.

According to the CDC (Centers for Disease Control, 2023) some respiratory exposures can result in the long-term development of “reactive airway dysfunction syndrome (RADS)” This is a type of chemical induced asthma and is a life-long condition. I personally know of 2 ALS providers who were exposed to chlorine gas in a pool incident on the job and both ended up retiring from their service and still have lifelong breathing problems as a result.

While overall, the recovery from chlorine exposure is good, the greatest risk is pulmonary edema. (Guldner GT, 2023) writes that “Pulmonary edema appears to be the most common cause of morbidity for moderate-to-severe exposures.” This is because chlorine (CL2) reacts with water in the body at the cellular level.

As mentioned previously, CL2 reacts with Water (H2O) to form hypochlorous (HOCL) acid and hydrochloric (HCL) acid along with free oxygen radicals (those pesky oxygen radicals!)

                CL2 + H20 < -- > HCL + HOCL < -- > 2HCL + O-

These two acidic compounds in the lungs are believed to cause the most damage to the body in chlorine exposure. It’s suspected that one form of damage is the release of oxygen, and HCL produces significant tissue damage. The other belief is that the HOCL penetrates cells, reacts with cytoplasmic proteins, and destroys cell structures. These symptoms can be delayed or immediate.  The unfortunate result is with acute exposure to chlorine that develops into pulmonary edema, there is an increased mortality for the patient, and there isn’t anything we can do about it. Once we've gotten to the stage where the patient has developed significant pulmonary edema and has suffered tissue damage from the conversion of CL2 to HCL and HOCL, the definitive treatment is pulmonary lavage in hospital and long-term management.... there's nothing we can do for them, and that's what makes chlorine so nasty. This is the mechanism that will eventually kill the patient as well with the high concentration (430 ppm+ exposure)

Vajner JE 3rd (2013) references several studies on chlorine inhalation. They found that 90% of exposures to chlorine gas were absorbed in the hypopharynx at low concentrations. It is presumed that, in many cases, the inadvertent mixing of household chemicals does not generate very concentrated amounts of chlorine gas.

Higher concentrations of chlorine gases are expected to penetrate the airways deeper, which is possible by mixing chemicals in confined spaces like smaller bathrooms.


Risks to Crew:

Exposure to chlorine gas and/or exposure to liquid chlorine.

Crews must not expose themselves to gas without proper equipment. If crews do not have access to SCBA, they must not enter an immediate danger to life and health (IDLH) environment. Chlorine gas is extremely hazardous to your respiratory tract (see the above information). Conduct a risk-benefit analysis for an emergency grab if appropriate. Still, the best advice is to wait for appropriate providers with SCBA to make entry to grab the victims if they cannot remove themselves from the environment.

Consider starting a truck or rescue squad company for a positive pressure ventilation fan (PPV) for forced air decontamination as soon as possible. Also, start a hazmat company as soon as possible.

Risks to Others:

As always, refer to local protocols and SOPS

Refer to ERG; but for an uncontrolled unmitigated hazmat release of suspected chlorine (mixing of bleach and vinegar (acetic acid) or ammonia makes chlorine gas), our initial standoff under the (U.S. Dept of Transportation, 2024) is 100M (330ft). We should consider evacuating the surrounding apartments as well to a safe area and initiate a hazmat response to ventilate and meter the subject apartment and adjacent units to clear the area for the safety of residents. It is also a consideration for shelter in place with more modern construction being more "air-tight" than older construction, as always refer to local authorities and experts whenever possible.

Chart for Effects taken from (Yetman, 2020)

What’s next?

Communication with the receiving facility is paramount. If possible, it is highly recommended to conduct a dual consult with online medical consultation (OLMC) and poison control (US 1-800-222-1222) or Poison X (CA 1-1-844-POISON-X) with any questions for treatment not covered already by protocols. Refer to the hazmat team and local SOPs for hazard mitigation of the scene. A patient’s belongings should be removed and bagged and left on scene with the hazmat team; and the patient covered appropriately for their decency as well as to ensure they are covered for environmental concerns (heat/cold etc).

Always inform the hospital that the patient was coming from a contaminated environment and to what extent they have been decontaminated.

Increased outreach to the community in education for not mixing household chemicals and general safety in cleaning supplies.


Current and historical uses of Chlorine:

Chlorine is used as a disinfectant agent for swimming pools. It’s also used in many industries to produce bulk products, paper products, PVC and other solvents. It can be used to make dyes, textiles, paint, and other medications. Historically it was used during WWI as a chemical weapon, it was also used as a weapon in 2007 in Iraq. The CDC (Guldner GT, 2023)reports over 6300 exposures to chlorine in the US in 2016, making it a common emergency, however these were not limited to just household chemical mixtures. According to the CDC, approximately 35% (2205) of those were related to accidental household chemical mixtures.

-The Hazmat Medic



Borron, S. W., Bronstein, A. C., Fernandez, M. C., Hall, A. H., Hays, D. P., Hurley, W., . . . Wood, A. (2014). Advanced Hazmat Life Support Provider Manual (4th ed.). (F. G. Walter, J. L. Schauben, R. Klein, & R. G. Thomas, Eds.) Tuscon, AZ: University of Arizona - Arizona Board of Regents.

Centers for Disease Control. (2023, 02 07). Chlorine. Retrieved from CDC.Gov:

Guldner GT, M. A. (2023, Jun 26). Chlorine Gas Toxicity. Retrieved 07 01, 2024, from StatPearls:

National Library of Medicine. (2023, 11 2). Chlorine Poisoning. Retrieved from Medline Plus:

U.S. Dept of Transportation. (2024). Emergency Response Guidebook for Hazardous Materials. 

Vajner JE 3rd, L. D. (2013, 9 9). Case files of the University of California San Francisco Medical Toxicology Fellowship: acute chlorine gas inhalation and the utility of nebulized sodium bicarbonate. J Med Toxicol. doi:10.1007/s13181-013-0309-8

Yetman, D. (2020, 05 29). Why you should not mix bleach and Vinegar while cleaning. Retrieved from Healthline:



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