Is Soot a Health Hazard?
Restoration professionals should make it a practice to analyze the substance they are cleaning, especially when it comes to fire losses.
For this article, let’s analyze why we should consider soot — smoke residue on surfaces — a potential health risk for restorers.
The combustion efficiency of materials is variable.
An alcohol lamp or propane torch burn cleanly and produce no noticeable odor or residues.
Most materials don’t burn cleanly, creating odor and residue.
The materials burning, availability of oxygen and the combustion temperature all have a significant effect on fire-related residues.
Fires lacking oxygen produce a significantly wider range of compounds, many of which are toxic.
Partial oxidation of carbon produces carbon monoxide; nitrogen can yield hydrogen cyanide, ammonia and nitrogen oxides.
Chlorine (PVC) or other halogens may produce hydrogen chloride, phosgene, dioxin, chloromethane, bromomethane and other halocarbons.
Pyrolysis (chemical change caused by heat) of burning materials results in large quantities of hydrocarbons, both aliphatic (methane, ethane, ethylene, acetylene) and aromatic (benzene and polycyclic aromatic hydrocarbons (e.g., benzo(a)pyrene).
Heavier hydrocarbons condense as tar.
The presence of sulfur can form hydrogen sulfide, sulfur dioxide, and thiols. Residual smoke odors are caused by thiols adsorbed onto surfaces.
Partial oxidation of released hydrocarbons yields aldehydes (formaldehyde, acrolein, furfural, ketones, alcohols, e.g., phenol, cresols), carboxylic acids (formic acid, acetic acid, etc.)
Those are some big words. You can sum it up this way: Be careful you don’t simply think: “It’s just smoke or soot. No problem.”
Take it seriously
Unlike its charming use as stage makeup in the movie, “Mary Poppins,” this fine particulate has been linked to occupational hazards and health problems.
The occupational hazards of soot have been known for hundreds of years.
Percival Pott’s findings on the insidious effects of soot on chimney sweepers (scrotal cancer) in England during the 18th century was a major force in getting the British Parliament to pass the Chimney Sweepers Act of 1788.
The passage of the English Factory Acts beginning in 1833 marked the first effective legislative acts in the field of industrial safety.
Firefighters of today, in spite of extensive health and safety training and personal protective equipment, experience higher incidence of respiratory problems than the general public.
Did you know that:
- Wood smoke has more than 100 chemicals in common with cigarette smoke?
Soot classified as PM 2.5 — particulate matter 2.5 ¬µm (micrometer) in diameter — has been linked to significantly increased risk of death from lung cancer and other severe respiratory ailments. Fine particles of this size and smaller evade the body’s natural defense mechanisms and migrate deep into the lungs.
- Airborne particulate is invisible. There is wisdom in the adage “out of sight, out of mind.”
Soot outdoors is regulated by the EPA. It is a particulate matter classified as a “criteria pollutant” by the EPA, and is an air pollutant for which the agency has established a National Ambient Air Quality Standard, the outdoor 24-hour fine particle standard (35 micrograms per cubic meter).
Human exposure routes to soot include: Inhalation, skin or eyes and ingestion.
When it is impossible to keep toxic materials contained, it is important to remove contaminated air from the work area and replace it with clean air. Ventilation dilutes and removes airborne hazards and is an effective means of keeping toxic and nuisance materials out of your lungs.
Wear appropriate personal protective equipment (respiratory, skin and eye protection).
Use a three-step indoor air quality improvement program: Ventilation, filtration (HEPA) and adsorption (activated carbon) to restore indoor air quality following fire and smoke damage.
Our level of awareness is influenced by a combination of internal and external factors: Experiences, suggestions, impressions, imagination, monetary motivation, etc.
While fear of toxic mold continues to terrorize the public at large, the hazards of soot remain virtually ignored.
We must shift public opinion.
Knowledge that the acidic nature of fire-related residue may discolor and/or corrode materials should make us uneasy of the potential for adverse health effects.
Soot is a known hazard; shouldn’t hazardous labor rates be applicable?
Help raise awareness to soot hazards by giving nitrile gloves and appropriate dust masks to workers, claims personnel and claimants.
Under the terms of their insurance policy, the repair of structural components and personal property is covered.
Isn’t the policyholder also entitled to have the air in their home or office returned to a level equal to, or better than, before the fire?
Cliff Zlotnik is a veteran and pioneer of the disaster restoration industry.