Monday, May 12, 2008

Tear Gas - First Aid

I don’t know about you. After so many years of watching people in other countries (on TV) being attacked by tear gas, I have never bothered to learn anything about it till I saw it used for the first time in KL .

My first reaction to the tear gas scenes on the streets of KL was to ask “what should I do if I do get caught in the middle of such unfortunate incident while window shopping”?

How many Malaysian doctors know anything about how to treat those who are exposed? It was never in my medical syllabus nor in the syllabus of the local medical school I helped to plan.

The internet is a great source of information, including sites which give tips to intending activists what to prepare, how to dress and what to do should the police “over-react”!!. Do check it out if you need more details.

This blog is just a quick summary of the internet articles, just in case we may need to treat or help anyone or the innocent bystander ….

Tear gas is the name given to a number of chemical agents which cause irritation of skin, mucous membranes and airways, immediate tearing of the eyes and an increase in blood pressure and pulse. Agents commonly used include CN or Mace, which is sprayed in a weak water solution, CS which is burned, and produces symptoms as long as the victim is in the smoke, and CR which is more potent and longer lasting. CS, used by police to disperse riots, is often delivered in a fine powder via aerosol grenades. Another agent in personal protection spray canisters is capsicum powder, the active ingredient in hot peppers. It is harder to remove from the skin and has the capacity to cause first degree burns.

Tear gas and pepper spray can be sprayed from small hand-held dispensers or large fire-extinguisher size tanks. Pepper spray also comes in plastic projectiles which are fired at the chest to knock the wind out of a person, who then takes a deep breath, of pepper from the burst projectile.

Tear gas is most commonly deployed via canisters, which are fired into crowds, sometimes directly at people. Heavy-duty gloves should be worn for those who may wish to handle hot tear gas canisters as they are extremely hot. Be aware that the time it takes you to throw it will allow you to be heavily exposed.

The exposed person complains of burning of the eyes, nose, mouth, and skin; tearing and inability to open eyes because of the severe stinging; sneezing, coughing, a runny nose, and perhaps a metallic taste with a burning sensation of the tongue, nausea, vomiting, and abdominal pains.

Discomfort from tear gas usually disappears after 5-30 minutes, while the worst pepper spray discomfort may take 20 minutes to 2 hours to subside. The effects of both diminish sooner with treatment. Redness and edema may be noted from one to two days following exposure to these agents. Because pepper spray penetrates to the nerve endings, its effects may last for hours after removal from the skin.

First Aid

Segregate victims lest they contaminate others.

  • Medical personnel should don gowns, gloves, and masks, and help victims remove contaminated clothes (which should be placed in plastic bags and sealed) and shower with soap and water to remove tear gas from their skin.
  • Exposed eyes should be irrigated with copious amounts of tepid water for at least fifteen minutes. If eye pain lasts longer than 15-20 minutes, examine with fluorescein for corneal erosions, which may be produced by tear gas.
  • Look for signs of, and warn patient about, allergic reactions to tear gas, including bronchospasm (especially those with history of asthma) and contact dermatitis.
  • Do not rush to help or allow other helpers to rush in heedlessly and themselves become incapacitated.

What to do if you are the inadvertent target of tear gas or water cannon laced with irritating chemicals:

* STAY CALM. Panicking increases the irritation. Breathe slowly and remember it is only temporary.

* If you see it coming or get a warning, put on protective gear, if able, try to move away or get upwind.

* Blow your nose, rinse your mouth, cough and spit. Try not to swallow.

* If you wear contacts, try to remove the lenses or get someone to remove them for you, with CLEAN, uncontaminated fingers.

Warning to those who are planning to attend gatherings that may attract “tear gas abuse” - Don't put vaseline, mineral oil, oil-based sunscreen or moisturizers on skin as they can trap chemicals.

Gas masks provide the best facial protection, if properly fitted and sealed. Alternatively, goggles (with shatter-proof lenses), respirators, even a wet bandana over the nose and mouth will help.

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