Beyond the Rule of Thumb
Survival Tip 47
Besides learning from your own on-the-job experience, one of the best ways to discover how to safely manage emergency incidents is to learn from the experience of others. In this way, you can determine what worked, what didn’t, and what steps to take when faced with similar circumstances. This type of learning is critical when dealing with incidents that involve hazardous materials because many of them are unique and may occur only once in your entire career. Remembering what someone else did years earlier, whether in your department or elsewhere, could offer valuable clues on what you should do and, more importantly, not do!
This month’s column presents various situations faced by first responders and questions posed to them; they were not sure of how to respond to some of these questions. Suggested answers appear at the end of the column.
I like to tell my students that although the minimum passing score on the written exam for hazardous materials awareness and operations-level training is 70 percent, the passing score in the real world is nothing less than 100 percent. It’s what you don’t know that will kill you.
1. You respond to a report of a leaking 55-gallon drum loaded in a tractor trailer that is parked at a highway rest area. During your initial size-up of the incident, you notice that the trailer is a refrigerated van, commonly referred to as a “reefer.” You wonder why a hazardous material would be loaded on a trailer normally dedicated to hauling food. Are there any safety issues that should be of concern regarding the type of trailer involved in the incident?
2. While responding to a report of a suspicious odor in a building, you receive additional information that three occupants are feeling ill. On arrival, you learn that all occupants have been evacuated. What is most likely the safest way to determine the source of the odor?
3. Several units respond to a report of a brush fire on a dry and windy day. The fire, which is in a field containing tall brush, is quickly spreading to a nearby construction site. Parked at the site are two 48-foot van trailers. One trailer displays “explosive” placards, and there are no placards on the other. What should be your concerns regarding these trailers as fire exposures?
4. During an incident involving an overturned tractor trailer, the hazardous materials team retrieves the shipping papers from the truck cab. You review these documents and determine that the trailer contains several drums of a flammable liquid and two compressed gas cylinders containing a nonflammable gas. There is no outside evidence of a leak; team members prepare to make entry to determine if any of the containers have been damaged. However, despite the bills of lading indicating the cargo, once inside the trailer, team members are unable to locate any of these containers. What is a likely explanation, and what might have been overlooked during your initial size-up?
5. You respond to an incident involving a highway cargo tank containing a corrosive liquid. On arrival you discover a pencil-sized hole on the right side of the container about two-thirds of the way up. Besides the obvious hazards of the liquid to personnel and the environment, can the liquid potentially affect the integrity of the container; if so, how?
6. During size-up of an incident involving a liquid leaking from the rear of a delivery truck, you learn that there are several different liquids onboard. Some are regulated as hazardous materials; others are not. How can you determine which of these items is the one leaking?
7. On arrival at the scene of a fully involved structure fire at a paper warehouse, you discover a 1,000-gallon propane tank at the rear of the building. There is direct flame contact on the tank, and the tank’s relief valve has opened. You believe that the operating relief valve will prevent the tank from exploding. Are you correct?
8. As a member of an EMS crew, you transport a patient who has been exposed to a hazardous material at a chemical factory. The patient was properly decontaminated, and you obtained a copy of the material safety data sheet (MSDS) before leaving the scene. However, to effectively treat the patient, a doctor at the hospital asks for additional information on the chemical composition of the material. You relay the doctor’s concerns to first responders still at the scene. The first responders are told by a representative from the factory that the desired information is a trade secret and refuses to release it. Is there anything that can be done to help save the life of the patient?
9. During another incident involving a contaminated patient, the individual refuses treatment at the scene. What information should you refer to prior to allowing the patient to sign the refusal statement on the prehospital patient care report?
10. You are on-scene at an incident involving three 55-gallon drums that have been abandoned in a wooded area. One drum displays a corrosive label, and the other two display combustible liquid labels. You inform a police officer on-scene that these materials are considered to be hazardous waste because the containers have been abandoned and that the suspect who they believe is responsible can be charged accordingly. Is your assumption correct?
11. You respond to an incident involving a chemical leaking from the rear of a delivery truck and discover that the material is a liquid oxidizer. During your size-up of the incident, what should be one of your concerns regarding the location of the vehicle?
12. What are three considerations for the selection and use of air-purifying respirators?
13. What are two considerations when deciding to use an underflow dam to contain a hazardous material that has spilled onto a body of water?
14. When reviewing highway shipping papers that contain entries for regulated hazardous materials, what is meant by PG I, PG II, and PG III? Does any one of them mean that a particular chemical is more dangerous than others?
15. When using an atmospheric monitor, what is one aspect of the detector that first responders must know about to obtain accurate and reliable readings?
ANSWER KEY
1. Although some hazardous materials are temperature sensitive, most often the reason these items are loaded onto “reefer” trailers is for backhaul purposes. As an example, a tractor-trailer travels from Florida to New Jersey hauling produce. Rather than travel back to Florida empty, the driver can arrange for a “backhaul” load that will provide revenue for the return trip. The concern for first responders in this scenario is that reefer trailers usually have metal floors to facilitate cleaning and many corrosive materials will generate hydrogen gas on contact with metal. The result is that a focus on the corrosive characteristics of the leaking hazardous material can allow you to overlook the potential for a dangerous concentration of a highly explosive gas.
2. Rather than enter the building to “sniff around,” I have learned that the source of an odor in a building is usually best determined by asking questions of the occupants, especially those responsible for management and/or maintenance of the facility. Questions to ask include the following:
A. What chemicals, if any, are stored or used on-site?
B. Was any maintenance work performed recently that involved the use of chemicals, such as painting, floor finishing, or cleaning of clogged drains?
C. Did any outdoor maintenance work that involved the use of chemicals take place near HVAC air intakes?
D. If you suspect that certain chemicals are involved, can you obtain a copy of the MSDS for each one? If so and if there are individuals who are complaining of exposure, can they describe the odor? If so, you may be able to compare their statements with the descriptive characteristics of the chemical found on the MSDS. You may also be able to compare their symptoms with those listed on the MSDS. Always remember that although some patients may have true medical problems related to chemical exposure, the source of symptoms in others may be more psychological than physical.
E. Another potential source of upper respiratory distress in patients is exposure to “pepper spray.” In one situation, first responders were faced with more than a dozen patients complaining of watery eyes and throat irritation. Once removed from the building, their symptoms began to subside. When all other potential sources of an airborne foreign substance were exhausted, we questioned the occupants to determine if anyone had a pepper spray canister in their possession. We soon learned that one female occupant did in fact have one attached to a key chain. This was placed in her purse, and she remembered dropping the purse to the floor just prior to feeling ill. It was later determined that the “shock” of the purse’s hitting the floor likely created sufficient force for a momentary release of the pepper spray.
3. During this incident, first responders must remember that placards are for use when hazardous materials are transported during commerce, not when the trailer in which they’re contained is used for storage. As such, the trailer with no placards could contain any type and quantity of hazardous materials and would not require placards. The trailer displaying the “explosive” placards is an obvious concern for first responders and, naturally, calls for an evacuation of the immediate area. Responders should check with the permitting department within their locality to determine if permits are required for storage of explosives; if so, check to see if a permit has been issued for the site. What the responders might discover is that the owner of the trailer placed expensive construction equipment inside the storage trailer and used the “explosive” placard to ward off potential thieves.
4. Trucks containing multiple shipments will have multiple shipping papers. As the driver makes deliveries, the bills are signed by the consignee who receives the material. When reviewing the bills, if the driver is available, he should be able to tell you which items have been delivered and which are still on the truck. Without the driver, you can look for a “received by” signature on a bill or perhaps determine if the “consignee” copy of the bill is missing, meaning that the material has already been delivered. Remember, however, that if you are able to isolate bills that have been delivered, check them to be sure that no items, especially hazardous materials, were refused for damage. As an example, you might find a bill for 10 pails of a flammable liquid that has a “received by” signature, but the bill might also have a notation indicating that one pail was refused because it was dented. That pail will most likely still be on the truck.
5. Experience has shown that leaks that appear on cargo tanks containing corrosive chemicals are often the result of a failure of the tank lining that protects the metal tank from the aggressive characteristics of the liquid. The concern for first responders is that although the hole will appear small at first, it will get progressively larger during the incident. Also, rather than get larger in diameter, the breach may move in a horizontal or vertical direction, depending on the direction of the damaged lining. Therefore, patching the hole without first removing the contents from the tank may mean that the breach can extend beyond the patch and continue leaking. Instead, you may need to offload most, if not all, of the product prior to any attempt to install a patch. Remember that even though the leak will stop once you offload the product, most motor carrier safety officers will likely require that the breach to be covered to move the trailer from the incident site.
6. If the truck belongs to a company that routinely transports these materials, the driver or a safety representative from the company may be able to provide a description. If not, obtaining copies of the MSDS can help. Stated descriptions such as a “milky white substance” or a “brown viscous liquid” can then be compared to what first responders observe (hopefully through binoculars). Through a process of elimination, they should have a better idea of which material is leaking. Shipping papers are not required to have MSDS attached. Instead, there will be an emergency contact telephone number for regulated hazardous materials responders can call to obtain a MSDS. For shipments of nonregulated hazardous materials, you will need to contact the shipper as stated on the bill of lading. However, be aware that the shipper may not have a copy of the MSDS because it may only handle the product. If that is the case, the shipper should be able to provide the name and contact information for the manufacturer. Likewise, you may also consider contacting the consignee as stated on the shipping paper; if it uses the product, it will likely have access to its MSDS.
7. In this situation, remember that the fire heating the tank and causing the relief valve to open is also probably contacting the tank metal in the vapor space above the liquid propane. By doing so, the heat is weakening the metal. When the tank shell becomes too thin to withstand the ever-increasing pressure of the heated liquid, the tank will likely rupture even though the relief valve is operating.
8. First responders at the scene can inform the company representatives of the following relative to section (i)(2) of Occupational and Safety Health Administration (OSHA) standard 1910.1200 (Hazard Communication):
Where a treating physician or nurse determines that a medical emergency exists and the specific chemical identity of a hazardous chemical is necessary for emergency or first-aid treatment, the chemical manufacturer, importer, or employer shall immediately disclose the specific chemical identity of a trade secret chemical to that treating physician or nurse, regardless of the existence of a written statement of need or a confidentiality agreement. The chemical manufacturer, importer, or employer may require a written statement of need and confidentiality agreement…as soon as circumstances permit.
9. Always remember that many chemicals have “delayed health effects” following exposure. One example is pulmonary edema, which can result in death. Therefore, prior to allowing a patient to sign a “refusal statement,” first responders should ensure that the individual is well informed about potential health hazards. This information can usually be obtained from an MSDS, but if one is not available, consult with a representative from a company that manufactures the chemical or from a poison control center. If the patient refuses treatment after learning about the possibility of delayed effects, make sure you document your efforts to educate him.
10. One way for a container of a hazardous material to become classified as a hazardous waste is for someone to abandon the container. It’s the same chemical, but because of the circumstances of where and how the container is found, different laws apply. There are a number of legal characteristics that help define hazardous waste—among them, ignitability (flammability) and corrosivity. First responders must be aware that these differ from the characteristics for hazardous materials as defined by the U.S. Department of Transportation (DOT). For example, when dealing with combustible liquids, the DOT definition is a liquid with flashpoint above 141°F. However, despite the presence of a red label with a “flame pictogram” required by the DOT, if a container of combustible liquid is abandoned and the material is now considered to be a waste, according to 40 CFR Part 261 Subpart C, it is not considered to be an “ignitable” hazardous waste, because this law defines an ignitable waste as one with a flashpoint of less than 140°F. Of course, the material may have other characteristics that will help define it as a hazardous waste, but your assumption that it is an ignitable hazardous waste only because you observe DOT labels could get you into legal trouble.
Likewise, the DOT definition of a corrosive material is not based on the pH of the chemical. In one instance, several abandoned drums displayed DOT “corrosive” labels. Despite these labels, the material was not considered to be a “corrosive hazardous waste” because, following laboratory analysis of the material, the pH was determined to be “10.” However, according to the law cited earlier, the definition of “corrosive” hazardous waste is a material with a pH less than or equal to 2 or greater than or equal to 12.5. Because of this, the suspect arrested for abandoning these containers could not be charged with violation of hazardous waste regulations. Instead, he was charged with nothing more than littering and trespassing on private property.
11. Determine if the vehicle is parked on asphalt. Experience has shown that certain oxidizers are sufficiently unstable and will react with an oil-based pavement such as asphalt, creating plumes of smoke with the potential for open flame. In one such instance, our strategy was to “dilute” the liquid oxidizer by opening a nearby fire hydrant and allowing the runoff to enter a nearby storm drain. Note that before employing this tactic, which had been recommended by the Emergency Response Guidebook (flood fire area with water from a distance), we checked with both the manufacturer of the product and the state environmental agency to make sure our actions would not make the situation worse.
12. Three considerations for selection and use of air-purifying respirators are as follows:
A. A minimum oxygen concentration of 19.5 percent.
B. A cartridge that is effective against the chemical(s) in the air.
C. A certification indicating that the user has passed a fit-test for the respirator in accordance with OSHA 1910.134.
13. Two considerations when deciding to use an underflow dam are as follows:
A. Does the material mix with water? If so, an underflow dam is useless.
B. If the material does not mix with water, does if float on water? If so, an underflow dam will most likely work to help contain the spilled material.
14. The letters “PG” refer to “packing group.” According to 49 CFR, Part 172.101, “Packing Groups I, II, and III indicate the degree of danger presented by the material is either great, medium, or minor, respectively.” Therefore, when reviewing a shipping paper with entries for hazardous materials without your knowing anything else about the chemicals involved, first suspect that materials assigned a packing group of I will likely be more dangerous than those with a packing group of II or III.
15. When using an atmospheric monitor, first responders MUST know the “response time” of the device. This is the amount of time that, depending on the concentration of gas being measured, is required for the device to provide an accurate reading. The exact response time, which can usually be found in the owner’s manual that accompanies the device, can sometimes be 30 seconds or longer. Remember that in atmospheres with a high concentration of gas, readings will be obtained almost instantaneously. It is situations with lower concentrations of gas that can get first responders into trouble. As an example, if a monitor fails to provide a reading after only a 10- or 15-second exposure to the atmosphere (when the response time is 45 seconds), it may be assumed that no gas is present in the area. This assumption could be wrong, and unless the person using the device knows to wait at least 45 seconds to obtain a reading, decisions on managing the incident could be based on incorrect information. As with all things in emergency services, this could prove deadly.
Questions or comments on this or any other monthly Hazardous Materials Survival Tip may be directed to Steven De Lisi at HazMatSurvivalTip@comcast.net
Click here for more info on Steven De Lisi’s book, Hazardous Materials Incidents: Surviving the Initial Response.
Steven De Lisi recently retired from the fire service following a 27-year career that included serving as the deputy chief for the Virginia Air Guard Fire Rescue and a division chief for the Virginia Department of Fire Programs (VDFP). De Lisi is a hazardous materials specialist and, as an adjunct instructor for VDFP, he continues to conduct hazardous materials awareness and operations-level training for fire suppression and EMS personnel. De Lisi began his career in hazardous materials response in 1982 as a member of the hazmat team with the Newport News (VA) Fire Department. Since then he has also served as a hazardous materials officer for the Virginia Department of Emergency Management; in that capacity, he provided on-scene assistance to first responders dealing with hazardous materials incidents in a region that included more than 20 local jurisdictions. De Lisi has a master’s degree in public safety leadership and is the author of the textbook entitled Hazardous Material Incidents: Surviving the Initial Response (Fire Engineering, 2006).
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Subjects: Hazardous materials response, firefighter hazmat training,
