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Phase 1 Unknown Odors

There are three main issues facing responders at the scene of truly “unknown” hazardous materials incidents. Over the course of three (3) months posting, we will examine beginning today with section 1 “unknown odors” we will explore these issues at the core of information needed by emergency responders as they arrive on an incident. Having the required data from these three elements allow the team to progress through the initial response to set-up of tactical activities and finally the orchestration of a decontamination system. Understanding these three components can give your response team a skeletal structure for operating a successful response throughout the entire incident.

The first of which is indicating odors either reported at the scene by “affected” individuals, or through dispatch by way of the initial call for response. Some of these agents can be identified by their scent, at levels below their PEL (Permissible Exposure Limit) from varying distances.

The second is the “exposure consequence” of these agents. What are their effects on the human body, and what can we expect at one of these incidents. How can these “affects” be treated in the field by the first responder? With what materials do responders need access to, either quickly, or from a large storage supply?

Lastly, how shall we decontaminate victims, responders, and our equipment? This (series) of articles shall answer these three pressing questions for the emergency response arena. We shall begin with this months’ issue on unknown odors.

There are three “Main” groups of both toxic and hazardous materials that frequently evolve vapors that are discernible from a distance below their respective PEL’s. TIM’s or toxic industrial materials are a relatively wide array of chemical compounds used frequently throughout industry. Hydrocarbons, a smaller group, usually consisting of flammables and corrosives also frequently shipped and used in industrial applications. Halogenated solvents are the smallest group and usually known for exhibiting the major hazard aspect of toxicity. These are listed in brevity below;

1] TIM’s (Industrial precursors)

2] Hydrocarbons

3] Halogenated Solvents

This is NOT an endorsement for using this technique in any way for investigative identification of these hazardous materials. Always practice your “safety” detection protocols when attempting to identify and or monitor hazardous materials. This said, the fact of the matter is, “affected persons” will call in the alarm while noting definite smells or odors, and they will probably also report them to 911 dispatch. If these individuals have moved away from the hazard release exclusion zone, either by accident, on purpose (fear) or suspicion after noting the odor, they may be unaffected by the release and offer the responder a wealth of information if they can be located for an interview.

A list like this should be carried, or accessible to all emergency responders that may be called to a chemical incident. First responders using nothing more than an “indicating odor” can prevent civilian exposure by practicing evacuation, thus eliminating future patients, while awaiting the Haz-Mat Teams’ arrival.  A note about the halogenated solvents; while the odor threshold in the following charts exceed the PEL, remember that this value is for unprotected respiratory exposure “over” a 8 hr duration. A “threshold” refers to a discernible odor that causes the individual to shy away from its source. If responders are not familiar with some of these common smells a good training procedure to locate the non-toxic versions of these odors and create a “quiz” to detect and identify these odors in preparation of an actual response. This can be implemented by your training coordinator and be entertaining as well as beneficial to the Team as a whole.

TIM’s (Toxic Industrial Materials)

pH          Odor                  Industry               Material         Detectable Odor

Acid          Almonds                 Plating                  Hydrogen cyanide     0.05 to 5 ppm

Acid          Chlorine                  Water                   Chlorine                    0.5 ppm

Acid        Green Grass      Metal/Grain Storage    Nitrogen Dioxide      5 ppm

Acid        Green Grass      Electricity/Welding      Phosgene                  1 ppm

Acid        Rotten Eggs      C.S./Petroleum             Hydrogen Sulfide      5 ppb

Acid        None/Low        Refrigeration                CO2    74000ppm/acid gas smell

Basic       Ammonia           Ref/Blueprints            Ammonia                   5 ppm

Basic       Fishy/ Ammonia      Tech                     Dimethylamine           unknown

Basic       Dead Animal      Chem/reclamation     Monomethylamine      unknown

Basic       Solvent               Chem/Cleaning         Analine/Pyridine/Morphaline  1 ppm

Neutral   None                    Refrigeration             Carbon Monoxide    74000ppm/acidic

Neutral   Onion/mustard     Battery Recharging    Stibine                        <1 ppm

Neutral   Garlic               Acetyl gen/Electronics   Arsine                         <1 ppm

Neutral   Foul Sulfurous       Natural Gas              Mercaptans                   ppb’s

Neutral   Biology Dissection   Plastics/Clothing    Formaldehydye             0.1 ppm

Neutral   New car plastic      Urethane plastic     Toluene diisocyanate        2 ppm

Neutral   Bitter chocolate   Electronics/exotic fuels   Decarboranes          unknown

Neutral   Nauseating          Electronics/exotic fuels     Diboranes             unknown

Neutral   Disagreeable        Fumigation                     Chloropicrin              < 1 ppm

Neutral   Dry cleaning         Degreasing/cleaning      Carbon Tetracloride    100 ppm

                                                                                 Methylene chloride      200 ppm

                                                                                 Methyl chloride            10 ppm

                                                                                 Trichloroethylene         20 ppm

                                                                                Perchloroethylene          5 ppm

                                                                                Chlorobenzene              < 1 ppm

Neutral      Heaviness in lungs        Refrigeration         Freons                       unknown

Neutral      Metal taste          Pigment mfg/ceramics    Metal dusts                unknown

While this is not a complete list for all TIM’s, it does cover many of the frequently released items that are heavily transported across the industry and frequently used in medium to large transportation vessels. Using this chart for TIM identification may give you an edge towards reducing exposure to responders and unprotected civilians.

Hydrocarbon Odors

Odor                                Material                                        Detectable Odor Level

Acrid, Sharp                            Acrylic Acid                                                 < 1 ppm

Airplane glue                           Toluene                                                           1 ppm

Aldehyde/alcohol                    Methanol                                                      about 100 ppm

Beer, Gin, Vodka                     Ethanol                                                        about 10 ppm

Gasoline                                  Benzene                                                        about 5 ppm

Boat resin                                 Styrene                                                          < 1 ppm

Chloroseptic, library paste        Phenol                                                            in ppb level

Elmer’s glue                            Vinyl acetate                                                   < 1 ppm

Fingernail polish remover        Acetone                                                            100 ppm

Green & Sweet                        Acetaldehyde                                                 about 1 ppm

Pumpkins (foul)                      Carbon disulfide                                              < 1 ppm

Sweet plastic, water (IPA)        Xylene                                                            < 1 ppm

Sweet garbage, solvent            Methyl Ethyl ketone                                        about 10 ppm

Vinegar                                   Acetic acid                                                       about 1 ppm

While the hydrocarbon family does have a slightly lower toxicity exposure, appreciate the higher hazard is flammability. If flammability readings are low, due to reduced % concentration released, you should assume a flammable hazard could elevate if the release should suddenly increase in volume.

Halogenated Solvents

Odor                  Possible contaminant            PEL                       Odor Threshold

Shoe dye                 Chlorobenzene                                 75 ppm                         60 ppm

Dry Cleaning          Perchloroethylene                             100 ppm                       27 ppm

                              Trichloroethylene                               100 ppm                      21 ppm

                              Chloroform                                           2 ppm                       85 ppm

                              Carbon tetrachloride                            10 ppm                      100 ppm

                              Trichloroethane                                 350 ppm                    200-500 ppm

Disagreeable          Methyl bromide                                   20 ppm                       unknown

Many of the cleaning industries have removed these hazards from neighborhood dry cleaning operations over the years, due to regulatory improvements. Industrially, they may still be transported in large quantities for industrial compound precursors used in industrial cleaning. Becoming well versed in “unknown odors” is the first step towards the identification of truly “unknown” spills. This skill will enable your response team to begin the identification process moving you forward towards a successful mitigation and response. Stay tuned to next month’s component dealing with medical “Exposures.”

                                             Haz Mat Mike

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