In the emergency response professions there are many examples of inhalation exposures to combustion gases and even chemicals. Most of these exposures are preventable but some may not be especially with chemicals that have poor or even non-existent warning properties. Consequently, responders need to be constantly vigilant so they may avoid needless inhalation exposures.
To become more aware of the dangers of inhalation exposures consider the following case studies;
On a cold December day two state troopers were overcome by toluene diisocyanate vapors after being involved in a spill on a highway. These law enforcers walked in the spilled material during the incident and when they returned to their own cruisers the heat in their vehicles warmed the material on their shoes and caused it to vaporize. The vapors were concentrated enough to make both of them pull over to the side of the road a short time later and radio for help. The arriving medical personnel found both troopers unconscious in their cruisers, removed them, and transported them to the hospital. Both troopers retired on disability and one died from complications a short time later.
In a September incident a refinery worker slipped and fell into a vat of hexane on a warm evening. The vat was four feet deep and the worker managed to keep his head above the liquid. An ambulance crew treated the worker at the scene by removing all the patient's clothing and giving high concentrations of oxygen. Despite these actions, the patient's condition deteriorated rapidly and a nearby medical transport helicopter was called for transport to a major area hospital. The patient arrived at the hospital alive, was treated and kept for observation for two days. The original ambulance and its crew, the medical helicopter and its crew, and the hospital emergency room became contaminated in the patient care efforts. Additionally, all emergency workers experienced temporary headaches, dizziness, and nausea from their exposure to the hexane vapors.
One January day in Broward County, Florida an engine company responded to a report of an odor of smoke at an apartment complex. Upon arrival there were no signs of fire or smoke but an employee directed the crew to a back bedroom of an apartment where smoke had been seen. The crew felt the door and found it to be cool to the touch and they did not observe any smoke. When they opened the door chemical vapors hit them and they were immediately overcome. It was found that the room contained concentrated vapors of sodium hydroxide, a white powder that had gotten wet and reacted. There were other chemicals present in the bedroom, which had been a storeroom for the apartment complex. One firefighter's blood tested immediately after the incident revealed high levels of chloroform and PCB's (polychlorinated biphenyls). All three firefighters suffered disabilities from the incident.
Inhalation is the number exposure route for unprotected responders because of the necessity of breathing to survive and also because of the exposure area within the lungs. There are millions of alveoli where oxygen is absorbed from the lungs into the bloodstream and unfortunately other gases can enter the blood through this 2 or 3-cell thick interface. If the surface area of these alveoli were laid out on a flat surface the average adult's lung tissue would cover approximately the size of a single tennis court. This massive surface area provides a toxic gas or vapors a great opportunity to cause harm. Magnify this area with the number of times per minute that a person inhales and exhales, especially while exerting effort, and it is easy to see why inhalation injuries often have immediate (acute) effects. Additionally, when the chemical agent enters the bloodstream more harm can occur.
Structure Fire Inhalation