First-Due Companies at Hazardous Materials Incidents


Regarding hazmat response, first and foremost, know your first-due area. Are there any industrial occupancies that store chemicals used to make consumable commodities or for other industrial purposes? If so, know what they are and where they are stored in the facility. These raw chemicals can produce the harmful effects described in their material safety data sheets (MSDSs). Because such chemicals are typically concentrated and in large quantities, exposure to even small quantities can cause harmful effects.

In contrast, in a residential setting, you will encounter materials that are sold to the general public. Although these commodities may include some nasty materials, they are typically not in concentrations that pose a great risk and are contained in small nonbulk packaging, which further lessens the magnitude of potential exposure.

Generally, however, remember that the public may be careless in handling dangerous materials and can also be quite litigious. As a result, chemical manufacturers do not allow the general public access to chemicals that are going to kill them quickly. Even though manufacturers may take great care to keep consumers safe, they cannot control the unsafe behavior of those who may mix rather benign chemicals and unknowingly create a real hazard.

Additionally, some old-school chemicals that are no longer commercially available, such as the pesticides diazinon and methyl parathion, may still be around. Although generally available 40 or 50 years ago, they have since been banned, and Grandpa just refused to get rid of it because “the new stuff just doesn’t work as well.” This is the reason we as first responders must know how to protect ourselves at a hazmat response while we determine if we can perform a rescue.

When firefighters think of hazardous materials, they first think of chemical protective garments or personal protective equipment (PPE), but most first-due companies are not likely to have specialized PPE on their rigs.

Remember your response priorities: life safety, incident stabilization, and property conservation (LIP). As first responders, your primary goal is life safety. The specialized suits for hazmat events are used during the incident stabilization and property conservation phases of LIP. The personnel who arrive when the victim is viable will make rescues only when dressed adequately and equipped with the appropriate detection equipment. But if the first-due companies wait until the guys with the hazmat suits arrive, the victim will be just that—a victim.


Rapid size-up is crucial in effectively determining whether a life hazard exists. I strongly recommend consulting Hildebrand and Noll’s Hazardous Materials: Managing the Incident when developing guides for safe operations.1 The authors’ eight-step process sets the framework for operating safely and efficiently at hazmat incidents. When adapting the framework to your department, make the steps specific to your staffing, training, and equipment capabilities. I have adapted this framework and modified Step 1, Site Management and Control, to include the activities of safely evaluating an atmosphere while performing a primary search in firefighting turnout gear, and reserve Steps 2-8 for the hazmat technicians who arrive to perform the offensive plug-and-patch skills and eventually terminate the incident (see the sidebar “Site Management and Control Checklist”). Essentially, Step 1 should include those activities that protect the public and first responders and increase the potential to save the lives of exposed victims. Above all, you must remember: During the initial investigation, you must determine if there is a true threat to life.

At the scene, observe the behavior and condition of individuals in the area. These are your “canaries,” or “hazmat meters.” If they are walking around complaining about an odor in a building but are not in any obvious distress, the threat to life is likely not too serious. However, be cautious. Although it may not seem that dangerous where those people are, they may be on the edge of a dangerous plume. It could get exponentially worse when you open the door to the adjacent apartment where a clandestine drug-cooking operation went awry.

The condition of people in the area will indicate whether the chemical’s concentration is below the permissible exposure limit (PEL), above the PEL, or above the immediately dangerous to life and health (IDLH) limit. If people are complaining about an odor but exhibit no exposure symptoms, it is likely below the PEL. If they are complaining about associated symptoms but are not unconscious or severely impaired, then it is likely above the PEL but below the IDLH for this unknown material. You can look up the exact definitions in the National Institute for Occupational Safety and Health (NIOSH) Pocket Guide to Chemical Hazards, but the following provides a basic guide for size-up:

  • Below the PEL: Individuals are asymptomatic; the environment is likely safe to enter, which is good for everyone.
  • Above the PEL/below the IDLH: Individuals display mild symptoms; not so good for victims. However, the responding fire department personnel are protected by their turnout gear, self-contained breathing apparatus (SCBA), meters, and detection papers.
  • Above the IDLH: Individuals are impaired or immobile—this is a true emergency. Fire department personnel, protected by their turnout gear, SCBA, meters, and detection papers, must rapidly remove and decontaminate these victims.

If you observe a patient who has self-evacuated and displays symptoms of chemical exposure, there may be other victims who were unable to remove themselves from the hot zone.


Based on your observations, reports from civilians on the scene, the physical symptoms described or observed, and the type of location/establishment, you can determine which chemical is most likely involved as follows:

  • A woman reports “a sweet odor” and has a headache—possibly hydrocarbons, probably aromatics such as benzene (carcinogens).
  • A man mentions a “pungent” odor and has burning eyes and throat—possibly acids or acid-forming halogens [e.g., chlorine (Cl2), fluorine (F2), bromine (Br2)] that were released from mixed cleaning chemicals in the residential setting.
  • No odor is observed, but people on scene are suffering from severe headaches—indicates carbon monoxide (CO), possibly from gas appliances.
  • A victim presents narcotic effects and appears to be in a euphoric state, accompanied by headaches, dizziness, fatigue, nausea, vomiting, and passing out—may indicate ketones.
  • A patient displays anesthetic effects, such as unconsciousness from recreational chemical drug use, coupled with a reported sweet odor—may involve ethers.
  • Victims with pinpoint pupils (miosis) may indicate organophosphate poisoning, more likely related to pesticides than to weapons of mass destruction. However, assume it’s a possible crime scene until proven otherwise. If a crime scene is suspected, notify law enforcement. When the primary search is completed, quickly sketch the scene from memory to convey what may have been disturbed during lifesaving efforts. When performing your primary search, do not move anything unless it is imperative to save a life or to continue the search.
  • A suicide by chemical asphyxiant could involve hydrogen sulfide, CO, or hydrogen cyanide. Treat this as a crime scene. If a crime scene is suspected, notify law enforcement. When the primary search is completed, quickly sketch the scene from memory to convey what may have been disturbed during lifesaving efforts. When performing your primary search, do not move anything unless it is imperative to save a life or to continue the search.



On arrival at a hazmat incident, act as you would at a structure fire and be appropriately aggressive based on risk vs. benefit. Size up the incident scene (the structure, the transportation incident, or the bulk storage area) for obvious signs of a release such as vapor clouds or puddles, and observe the condition of civilians in the area. Locate and question the 911 caller to determine the nature of the incident and whether the “hot zone” has been evacuated. To determine how large the hot zone should be, consult the U.S. Department of Transportation’s North American Emergency Response Guidebook (ERG), under the “Public Safety” section of the orange guide pages, consult the second bullet to determine your isolation distance.

The ERG recommends the following isolation distances:

  • Outside of a building
    —Unknown materials and gases: 330 feet
    —Liquids: 150 feet
    —Solids: 75 feet
    —If explosives are suspected, expand this to one-third of a mile.
  • Inside of a structure:
    —The structure is the hot zone. However, consider open windows and wind direction. Measure the above distances on the building’s leeward side.

As with a structure fire, do not rely solely on the word of someone in the street when he informs you that everyone has evacuated the building; perform a primary search. Similarly, on arrival at a commercial or industrial site, often workers have not been accounted for to ensure that all have evacuated, so you must perform a primary search.


Since the atmosphere has not yet been evaluated, the Occupational Safety and Health Administration (OSHA) assumes an IDLH atmosphere. During an emergency, time is crucial, and you must expedite a rapid investigation while ensuring the responders’ safety, so wear SCBA during the initial investigation. As it pertains to our response, in the following excerpts of OSHA rules from 29 Code of Federal Regulations (CFR) 1910.134, Respiratory Protection Standard, and Hazardous Waste Operations and Emergency Response (HAZWOPER) Standard, 29 CFR 1910.120, “the employer” is the fire department:

• 1910.134(d)(1)(iii) The employer shall identify and evaluate the respiratory hazard(s) in the workplace; this evaluation shall include a reasonable estimate of employee exposures to respiratory hazard(s) and an identification of the contaminant’s chemical state and physical form. Where the employer cannot identify or reasonably estimate the employee exposure, the employer shall consider the atmosphere to be IDLH.
• 1910.120(g)(3)(iii). Positive pressure self-contained breathing apparatus shall be used when chemical exposure levels present will create a substantial possibility of immediate death, immediate serious illness or injury, or impair the ability to escape.
• 1910.120(q)(3)(iv). Employees engaged in emergency response and exposed to hazardous substances presenting an inhalation hazard or potential inhalation hazard shall wear positive pressure self-contained breathing apparatus while engaged in emergency response, until such time that the individual in charge of the ICS determines through the use of air monitoring that a decreased level of respiratory protection will not result in hazardous exposures to employees.
• 1910.120(k)(2)(iii). All employees leaving a contaminated area shall be appropriately decontaminated; all contaminated clothing and equipment leaving a contaminated area shall be appropriately disposed of or decontaminated.


(1) Photos by author.


Decon shall be established prior to the entry into a hazardous atmosphere. This does not mean that you must establish a 14-station decon line prior to entry. A simple Urgent Patient/Rescuer decon station is appropriate. The driver can set up the decon station below while the officer is interviewing the 911 caller and the firefighters are preparing the meters and papers (photos 1, 2). Fully stretch a 200-foot preconnect, and designate this as your warm zone.


Remove the victim’s clothing with trauma shears and rinse the victim with water. If you encounter victims, immediately begin decon efforts. If you postpone decon to set up a structured decon line, people will die. The U.S. Environmental Protection Agency (EPA) has advised the following:

Contaminated runoff should be avoided whenever possible, but should not impede necessary and appropriate actions to protect human life and health. Once the victims are removed and safe from further harm and the site is secured and stable, the first responders should be doing everything reasonable to prevent further migration of contamination into the environment.2 [Emphasis in original.]

However, this guidance does not apply to nonlife-threatening situations when a hazmat team is making entry to perform technician level operations such as plugging and patching or overpacking a drum. In these circumstances, use a decon line that is appropriate for the hazard present.


When making your approach, move rapidly but cautiously, and observe your surroundings. Look for vapor clouds, and listen for the sounds of high-pressure gas leaking and the creaking or popping of expanding and failing metal containers. Observe your mother’s warnings of not playing in the puddles.

When making the initial approach, consider what to wear. If the substance’s MSDS is available, you need to know the following four things immediately:

  • Is it flammable? Section 1.7 of NFPA 30, Flammable and Combustible Liquids Code, 2008 edition, defines a flammable liquid as one whose flash point does not exceed 100°F, when tested by closed-cup test methods. As said before, it is likely that you don’t have specialized suits on your first-due apparatus. Even if you do carry chemical protective suits, your biggest hazard is flammability. Plastic will not protect you from that; think “shrink wrap.”
  • What is the IDLH value? If this number is low, then there is potential for concern. What are the units of measure? Parts per million (ppm) typically refer to an inhalation hazard, whereas milligrams per cubic meter (mg/m3) refer to an ingestion or injection hazard but also may refer to an inhalation hazard.
  • What is the vapor pressure (VP)? VP indicates the material’s tendency to evaporate. As the VP value increases, more vapors are produced, and the more vapors there are, the greater the danger. VP increases as the temperature increases. At 68°F, if the VP is <50 mmHg, it presents a low risk; between 50 and 100 mmHg, it’s a moderate risk; a VP >100 mmHg is a high risk; and a VP >= 760 mmHg indicates a gas.
  • What are the routes of entry? To determine how a chemical can hurt you, you must know how that chemical attacks you.
    —If there is only an inhalation hazard, then your SCBA is the tool of choice.
    —If there is an absorption hazard, the question is, “Is the hazard for liquid or vapor?”
    —Only for liquids: If there is a life hazard, go in wearing turnout gear and SCBA, and don’t get wet.
    —Vapor hazard: This is a Level A event, but if there is an immediate life hazard and you don’t have Level A PPE immediately available, you can wear your turnout gear with SCBA and use technology (i.e., metering and papers) to determine whether rescue efforts can continue.
    —Ingestion or injection hazard: You shouldn’t be doing either of these.

When looking at the above values, if I have a material with a high VP (>100 mmHg) coupled with low PEL and IDLH values, it is likely that I will find concentrations that will cause harm, especially in confined areas. Also, all flammable materials have inherently high VPs. Even if the material isn’t registering a reading on the LEL meter (minimum one percent or 10,000 ppm), the ambient concentrations are still likely way above that material’s PEL, especially if it is in an enclosed space. Although you need to consider these values for the people for whom you are searching, you need not be overly concerned about first responders, since we have SCBA and turnout gear for our protection. Couple aggressive search with appropriate ventilation, and you have increased the survivability for those civilians who are in danger.

Some texts incorrectly refer to turnout gear and SCBA as modified Level C protection; it is a Level B ensemble. Level C is a splash suit with an air-purifying respirator. Level B is a splash suit with SCBA. Turnout gear does provide some very limited and extremely expensive splash protection. This is a case of risk vs. benefit. The risk of ruining turnout gear is worth the benefit of saving a life. Also, if turnout gear with SCBA were considered level C, then 1910.120(c)(5)(iii) and 1910.120(q)(3)(iii) below would be contradictory. Additionally, we wouldn’t even be able to investigate a CO emergency with the equipment we carry on our apparatus—turnout gear, SCBA, and a meter.

• 1910.120(c)(5)(iii). If the preliminary site evaluation does not produce sufficient information to identify the hazards or suspected hazards of the site, an ensemble providing equivalent to Level B PPE shall be provided as minimum protection, and direct reading instruments shall be used as appropriate for identifying IDLH conditions. (See Appendix B for guidelines on Level B protective equipment.)
• 1910.120(q)(3)(iii) Based on the hazardous substances and/or conditions present, the individual in charge of the ICS shall implement appropriate emergency operations, and assure that the personal protective equipment worn is appropriate for the hazards to be encountered. However, personal protective equipment shall meet, at a minimum, the criteria contained in 29 CFR 1910.156(e) when worn while performing fire fighting operations beyond the incipient stage for any incident.
• 1910.120(g)(3)(v) The level of protection provided by PPE selection shall be increased when additional information or site conditions show that increased protection is necessary to reduce employee exposures below permissible exposure limits and published exposure levels for hazardous substances and health hazards. (See Appendix B for guidance on selecting PPE ensembles.)
• NOTE TO PARAGRAPH (g)(3): The level of employee protection provided may be decreased when additional information or site conditions show that decreased protection will not result in hazardous exposures to employees.
• 1910.120(g)(3)(iv) Totally-encapsulating chemical protective suits (protection equivalent to Level A protection as recommended in Appendix B) shall be used in conditions where skin absorption of a hazardous substance may result in a substantial possibility of immediate death, immediate serious illness or injury, or impair the ability to escape.

With all this said, do not come in contact with unknown liquids. If, during a primary search, you encounter a situation where there is a great risk of a splash from or engulfment in an unknown liquid, discontinue your search. Our SCBA is protecting us from the gases or vapors that may be present from the usual organic and inorganic liquids. The unusual gases that pose a risk to skin are caustic, acidic, or oxidizing; the appropriate detection papers can detect them. When these papers detect the presence of these gases, the incident is considered a Level A event, and first responders discontinue the primary search.

At a response in which you don’t have an MSDS, such as an unknown odor complaint, then you have to rely on science and experience. Contrary to the belief of many, an unknown substance does not automatically kick the response to a Level A event. You can wear your turnout gear with SCBA and use technology to see if your rescue efforts can continue.


• 1910.120(h)(2). Initial entry. Upon initial entry, representative air monitoring shall be conducted to identify any IDLH condition, exposure over permissible exposure limits or published exposure levels, exposure over a radioactive material’s dose limits or other dangerous condition such as the presence of flammable atmospheres, oxygen-deficient environments.

In making the initial search, you must ensure that you are not endangering yourself through appropriate metering and detection. The atmospheric hazard that poses the greatest risk is combustion, either by ignition of a flammable atmosphere or by a container overpressurizing and subsequently igniting. Bring your LEL meter. The standard four-gas meter [LEL, oxygen (O2), hydrogen sulfide (H2S), and CO] is the best, since it will ensure an accurate LEL reading coupled with the ambient oxygen content.

Also bring your thermal imaging camera (TIC) or infrared (IR) thermometer (i.e., the temperature gun). A standard TIC that does not indicate the temperature is useful in quickly scanning a large room with many containers to determine if one container is warmer than the others. However, you want to determine the container’s actual temperature. It may be warmer than the others because it is located in front of an HVAC duct and shows bright white on your TIC compared with the other containers in the room.

Also, you want to know if the container’s temperature is decreasing, maintaining, or increasing. So, if you do not have a digital temperature readout on your TIC, also bring an IR thermometer. When choosing an IR thermometer for use with hazmat, choose one that uses a Class 2 laser that generates less than 1.0 megawatts (mW) of power.3 This is a huge safety margin to ensure the sample isn’t ignited or, worse yet, detonated.

Additionally, know the distance to spot (D:S) ratio. If you are standing 40 feet from the target and the sensing spot is six feet in diameter, you are sensing the temperature of more than just the container in question. A good D:S is 35 feet:1 inch. If the material in a closed container is flammable or combustible, and this material has heated to its ignition temperature, then this material will ignite when it meets the oxygen in the air after the container ruptures from being overpressurized. When you hear escaping pressure, you hope to see a decrease in temperature. If you observe an increase in temperature with no obvious external source of heat, this escaping pressure typically indicates a chemical reaction internal to the container. If this is coupled with escaping pressure, it is likely a pressure-relief valve—worse yet, a component failure. Remember that most IR thermometers are not intrinsically safe, so ensure you are operating in a safe environment free of flammable gases.


Your next concern is, Is my PPE protecting me? Your turnout gear will do little to protect you from a caustic, acidic, or oxidizing gas, so you must use chemical detection papers to determine the nature of an unknown gas.

  • pH paper indicates whether a gas is caustic (it turns blue) or acidic (it turns red).
  • Potassium iodide paper indicates the presence of an oxidizing gas (it turns blue-violet or black).
  • Fluorine paper indicates whether hydrofluoric acid is present (it turns yellowish white). One could argue that the pH paper is sufficient, but knowing whether a calcium-seeking toxin is present is worth the pennies per strip that it costs. I am less worried about my fingernail beds and bones than I am about my heart, which has a strong affinity to the calcium in my blood. An extremely low calcium level may cause tingling (often in the lips, tongue, fingers, and feet), muscle aches, spasms of the muscles in the throat (leading to difficulty breathing), stiffening and spasms of muscles (tetany), seizures, and abnormal heart rhythms.4

Again, if these detection papers indicate a contaminant by changing color, then the incident is now a Level A event. Remember the OSHA excerpt 1910.120(g)(3)(v) above, “The level of protection provided by PPE selection shall be increased when additional information or site conditions show that increased protection is necessary.” Also, the rescue is no longer possible. If there is a victim out of your reach, and this person could not self-evacuate, then the damage to his lungs will not support life.


We must determine the presence of ionizing radiation to ensure that we are operating in a safe environment. Remember, in transportation, placards are not required on Radiation I and II materials if the shipping weight is less than 1,000 pounds. Also, in industry or a laboratory setting, the storage area may not be appropriately marked. Finally, don’t forget the potential for a radiological dispersion device.

A gamma dosimeter detects gamma only, which is good in that this is the energy that we are not protecting ourselves from while we are dressed in our full turnout gear with SCBA. However, if you want to rule out all ionizing radiation, use a survey meter with a pancake Geiger-Mueller (G-M) probe that is sensitive to alpha, beta, and gamma radiation. When using the pancake G-M probe, remember that you are reading counts per minute (cpm) rather than a dose rate or accumulated dose. When reading in cpm, the turn-back value is often two times the cold zone background level. Remember that most radiation detection devices are not intrinsically safe, so ensure you are operating in a safe environment free of flammable gases.

The U.S. EPA guidelines for emergency response for an adult who is not pregnant are as follows:


Many standard operating procedures across the country require the completion of long tedious forms and job aids and assessing the entry team’s vitals before entering the hazmat hot zone. This hurry-up-and-wait mentality is valuable when a hazmat technician is entering to perform offensive technician level skills to mitigate the release, not rescue people. I have outlined my Step 1; Steps 2-8 still apply when you have addressed life safety through primary searches that proved negative or when you have discontinued search because of metering and detection results. In using the above guide, you will ensure a safe operation that will maximize the chance for survival of those within the hot zone. Your SCBA will protect you from most of the contaminants you are likely to encounter. The meters and papers will detect the flammable, corrosive, and oxidizing gases and ionizing gamma radiation you may encounter and will indicate when you should discontinue rescue efforts and transition to standard hazmat entry protocols.


1. Noll, Gregory G., and Michael S. Hildebrand. Hazardous Materials: Managing the Incident, Third Edition.(IFSTA, 2005).

2. U.S. Environmental Protection Agency, “First Responders’ Environmental Liability Due to Mass Decontamination Run-Off,” Chemical Safety Alert, July 2000.

3. Houghton, Rick. Emergency Characterization of Unknown Hazardous Materials. (CRC Press, 2008), 239-240.

4. “Calcium,” Minerals and Electrolytes, Disorders of Nutrition and Metabolism, The Merck Manuals Online Medical Library: Home Edition for Patients and Caregivers,

JEFF CHANDLER is the Eastern Region’s supervising emergency response coordinator for the Connecticut Department of Environmental Protection’s Hazardous Materials Emergency Response Unit, which is responsible for hazmat investigation, mitigation, and remediation. He has 17 years of experience as a hazmat technician, including work as an environmental contractor. A 25-year veteran of the fire service, he has served as a volunteer assistant chief and a career captain. Chandler is a volunteer firefighter with the Mystic (CT) Hook and Ladder Company and a part-time career firefighter with the Preston (CT) Department of Fire and Emergency Services.

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