Hazmat IQ Post Fire Air MonitoringThe Good, The Bad and The Ugly
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BY STUART WEST, TORONTO FIRE ACTING CAPTAIN, STATION 111-B
he health and safety of firefighters has become omnipresent in this modern era of firefighting and the ways in which chemicals can harm the human body are now fairly well understood. With this in mind, some of our past practices have been altered or discontinued entirely. One of the more controversial practices that we no longer participate in is post-fire air monitoring for the purpose of determining when it is safe for crews to remove their SCBA while conducting overhaul operations. Knowing what we know now, it may seem difficult to comprehend for those of you who may have just been hired in the last few years. Post-fire environments are now known to be extremely toxic and through recent studies over the last 10 years it has now been documented quite clearly. It is no longer a question regarding whether SCBA is required in these environments. SCBA IS REQUIRED, FULL STOP. One doesn’t need an expensive meter to tell us that. However, just because we no
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longer conduct post-fire air monitoring to justify the removal of breathing protection, this doesn’t mean we’ve abandoned one of our most effective tools for ensuring a safe environment for all concerned.
What Is Smoke?
Smoke: “The airborne solid and liquid particulates and gases, evolved when a material undergoes pyrolysis or combustion, together with the quantity of air that is entrained or otherwise mixed into the mass”. Smoke is a complex mixture of toxic gases and particles which are generated from the vast array of materials that burn during a fire. A typical structure fire may generate literally tens of thousands of toxic chemicals and gases as a variety of materials and products undergo pyrolysis and ultimately combust. The toxic mixture of chemicals and gases contained in fire smoke is comprised primarily of carbon monoxide, carbon dioxide, hydrogen cyanide, ammonia, hydrogen chloride, sulfur dioxide, hydrogen sulfide, acids, and oxides of nitrogen. Other toxins may include acetylene, methyl mercaptan, nitric oxide, carbon disulfide, creosote, nitrogen dioxide, dimethyl sulfide, phosphine, ethylene, benzene, methylene chloride, lead, chromium, other metals, trichloroethylene, toluene, trichlorophenol, fluorine, acrolein, mercury, formaldehyde, glutaraldehyde, benzaldehyde, sulfuric acid, hydrochloric acid, arsenic, chromate, phenol, styrene, polycyclic aromatic hydrocarbons, and literally hundreds if not thousands more. One of the biggest health threats from smoke is from fine and ultra-fine particulate matter (PM). Fine particulate matter is anything 2.5 microns in diameter or smaller. Ultra-fine particles on the
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