Chapter 49 - Hazardous Materials

Vapor pressure

pertains to liquids held inside any type of closed container. Vapors released from the surface of any liquid must be contained for them to exert pressure. Vapor pressure directly correlates to the speed at which a material will evaporate once it is released from its container.

Systemic effect

physiologic effect on entire body or a specific system

Water reactive

substance will have a chemical reaction when mixed with water

Water soluble

substances that dissolve in water

secondary contamination

takes place when a hazardous material is transferred to a person from another person.

Dose effect

the greater the length of time or the greater the concentration of the material, the greater the effect probably will be on the human body.

Specific gravity

the measure if a substance will float or sink in water

ignition temp

the minimum temperature at which fuel vapor will ignite

Level D

typically not worn in hazardous materials incidents by anyone other than support personnel working in the cold zone. Worn when there is little or no threat posed by the released substance The responder is wearing no respiratory protection other than perhaps a dust mask.

DOT Class 8:

Corrosive substances

Emergency Decontamination

process of removing the bulk of contaminants from a person as quickly and completely as possible. Once you are properly protected, you should instruct the person to disrobe and remove as much of the hazardous materials from his or her body as possible. Give the person bags in which personal belongings and clothing can be placed. If the hazardous material is a powder, it should be brushed away first. If the hazardous material is water reactive, water should not be used for decontamination.

Level A

provides the greatest respiratory and skin protection from exposure to hazardous substances Fully covers the body and the self-contained breathing apparatus (SCBA) or other supplied air system worn by the responder. Suits are rigorously tested by manufacturers to determine resistance to many chemicals. Because they are considered to be "gastight," and completely cover the wearer, you may be asked to monitor or evaluate technicians for heat stress. You should familiarize yourself with the procedures for getting into and out of these garments.

Hazardous Material

A hazardous material is any substance or material that is capable of posing an unreasonable risk to human health, safety, or the environment when transported in commerce, used incorrectly, or not properly contained or stored

corosive

Corrosives are chemicals that include both acids and bases. Examples are toilet bowl cleaner, lye, and hydrochloric acid. Acids have a low pH (from 0 to 7), whereas bases have a high pH (7 to 14). Substances with either high or low pH can cause severe burns to the skin, eyes, and mucous membranes. Signs and symptoms include skin irritation, reddening or other discoloration, and blistering. Treatment is generally supportive. Ensure a patent airway, oxygenate the patient, treat for pain if indicated, and treat burns appropriately. Patients showing signs of pulmonary edema secondary to an inhalation exposure may need to be treated with diuretics.

DOT Class 1:

Explosives

Red

Fire

DOT Class 4:

Flammable solids, spontaneously combustible materials, and dangerous-when-wet materials or water-reactive substances

DOT Class 3:

Flammable/combustible liquids

DOT Class 2:

Gases

Blue

Health

Dot Class 9:

Miscellaneous hazardous materials/products, substances, or organisms

Operations

Operations-level personnel respond to protect nearby people, property, and the environment from the effects of a hazardous materials incident. Trained to operate in a defensive manner and not make direct, intentional contact with the hazardous substance. Because of the limitations of awareness-level training, many EMS agencies provide operations-level training for paramedics. Paramedics trained at the operations level may be called to the scene of a hazardous materials incident for stand-by or to treat patients outside of the hot zone.

DOT Class 5:

Oxidizing substances and organic peroxides

DOT Class 7:

Radioactive materials

Yellow

Reactive

Solvents

Solvents are substances that are capable of dissolving other substances. Liquids, solids, or gases (eg, pain thinner and nail polish). Give off potent vapors that can be inhaled and can also be absorbed through the skin. May require extensive decontamination. Respiratory exposure can cause immediate pulmonary symptoms such as pulmonary edema. Prolonged dermal exposure can cause symptoms as well, including cardiac dysrhythmias and seizures. In general, solvent exposures require much of the same basic patient care as with any other exposure. Pay special attention to the potential for vomiting if a solvent has been ingested. Vomiting may complicate the patient's airway and be a cause for chemical pneumonitis.

White

Special

Technician

Technician-level personnel may be directly involved in a contaminated atmosphere or be part of the hazardous materials response operation. May make direct, intentional contact with a spilled material to mitigate the problem. Training includes: Use of specialized equipment Care of patients during the rescue Management of the incident and of all personnel at the scene

DOT Class 6:

Toxic substances and infectious substances (The word poison or poisonous is considered synonymous with toxin or toxic.)

Awareness

Understand what hazardous substances are and the risks associated with them Understand the potential outcomes of an incident Recognize the presence of hazardous substances Identify hazardous substances, if possible Understand the role of the first responder awareness individual in the emergency response plan Determine the need for additional resources and to notify the communication center

Toxic products of combustion

Whatever objects are involved in a fire will break down in the heat and create a host of chemical by-products in the smoke. Toxic gases and other chemical substances found in the smoke will be determined by what is burning. Substances found in most fire smoke include soot, carbon monoxide, carbon dioxide, water vapor, formaldehyde, cyanide compounds, and many oxides of nitrogen

Level B

called for when the responder needs a high level of respiratory protection, but the released substance does not pose a lethal threat via skin absorption. Not fully encapsulating like level A Worn with SCBA, or supplied air on the outside of the suit Often worn by hazardous materials responders who are performing decontamination

Vapor density

compares the hazardous material gas to air (air has a vapor density of 1). If the gas is heavier than air, the gas will sink into little valleys and ditches.

Level C

designed to protect against a known substance. Provides minimal splash protection and is worn with an air-purifying respirator (APR) or powered air-purifying respirator (PAPR) that must have filters specifically chosen to provide protection against the known agent May be worn by receivers of exposed patients in the ED and law enforcement officers providing perimeter protection at the scene

Flammable range

expression of a fuel-air mixture, defined by upper and lower limits, that reflects an amount of flammable vapor mixed with a given volume of air.

Flash point

expression of the temperature at which a liquid fuel gives off sufficient vapors that, when an ignition source is present, will result in a flash fire. Low flash point liquids typically have high vapor pressures and can be expected to produce a significant amount of flammable vapors at all but the lowest ambient temperatures.

Primary contamination

is direct exposure of a patient to hazardous material.