Marking Systems & Other ID Tools

These make it easier for responders to identify hazardous substances and their potential hazards.

EMERGENCY responders have helped protect Americans from hazardous substance releases since our nation's beginnings. From the bucket brigades of colonial times to today's in-plant and community hazardous materials response teams, response workers have taken action during emergency releases to save lives, preserve property, and protect the public good.

However, their safety and the safety of others depends on knowing the identity of the hazardous substances involved in a release. Failure to identify hazardous substances may cause unnecessary fatalities and damage. For example, in November 1988, six Kansas City firemen were killed when the arson-initiated fire they were fighting caused the violent explosion of an unmarked truck-trailer parked at a highway construction site. Because the trailer's hazardous materials placards had been removed, the firemen were unaware of the danger it posed.

That's where hazardous substance container markings come into play. Markings give emergency responders the ability to identify the contents of a hazardous substance container quickly. Once responders identify a substance, they can understand the hazards and take proper actions to control a release.

Marking Types
Responders may face any one or more of six marking types:

  • Label--Any written, printed, or graphic material, displayed on or affixed to containers of hazardous substances. Labels are not intended to be the most complete source of information.
  • Placard--A DOT term to refer to a diamond-shaped "sign" posted on the outside of a transport vehicle.
  • Marking--Identification text printed on or affixed to the surface of a package or on a label, tag, or sign.
  • Sign--A board displaying the warning of, or safety instructions of, workers, responders, or the public who may be exposed to hazards.
  • Tag--Card, paper, pasteboard, plastic, or other material to identify a hazard. Tags are used as a means to warn employees who are exposed to hazards that are out of the ordinary, unexpected, or not readily apparent.
  • Marker--A "sign" used to indicate the location of an underground pipeline.

Marking Systems
Uniform marking systems make it easier for emergency responders to identify hazardous substances and their potential hazards:

  • NFPA 704. The National Fire Protection Association (NFPA) 704 system uses colored hazard ratings. The red diamond provides the flammability rating, blue the health rating, yellow the instability rating, and white any special rating.

    Often, an NFPA 704 sign is posted on the entrance to a facility. When this is the case, facilities record the number (0 to 4) that corresponds to the greatest hazard in the facility in each of the health, flammability, and instability categories. Other specific hazards within the facility would be identified in the white diamond.

    While the NFPA 704 system is widely used, it does not provide for the identity of the hazardous substance. Also, the ratings posted on the entrance to a facility don't necessarily reflect the hazards that may actually be faced by responders.

  • HMIS® III. The Hazardous Materials Identification System® III developed by the National Paint and Coatings Association also uses a colored rating system. The blue stripe provides the health rating, the red stripe the flammability rating, the orange stripe the physical hazard rating, and the white stripe the personal protective equipment rating. HMIS® III is a marking system dedicated to workplace hazard communication. Because it provides the hazardous chemical identity and various ratings, this system can be helpful to responders.
  • DOT. DOT calls for numbered and colored diamond-shaped labels and placards to signify the hazard of a "hazardous material" as follows:

    1. Explosive--Orange for all divisions.

    2. Gases--Red for flammable gases; green for non-flammable, non-poisonous compressed gases; and white with skull and crossbones for gas poisonous by inhalation.

    3. Flammable Liquids--Red.

    4. Flammable Solids--Red and white vertical stripes for flammable solids, a white top and red bottom for spontaneously combustible flammable solids, and blue for dangerous when wet flammable solids.

    5. Oxidizers--Yellow for all divisions.

    6. Poisonous Materials--White for all divisions.

    7. Radioactive Materials--Generally, a yellow top and white bottom.

    8. Corrosive Materials--A white top and black bottom.

    9. Miscellaneous Materials--Black and white vertical stripes on top and a white bottom.

    DOT does call for four-digit identification numbers on placards, orange panels, or white square-on-point configurations for certain hazardous materials and quantities.

    Some hazardous materials are not required to be labeled or placarded. Also, a "Dangerous" placard, which provides no identifying information, is allowed in some cases. Finally, labels and placards do not appear on all sides of a container. This makes it difficult for a responder if a cargo tank, for example, is overturned.

  • EPA. EPA requires a number of labels, including pesticide and hazardous waste labels. Every pesticide product must bear a label containing the name, an EPA registration number, and other helpful information.

    Before transporting hazardous waste or offering hazardous waste for transportation off site, a company must mark each container of 110 gallons or less with the words, "HAZARDOUS WASTE" and other required verbiage, including the proper shipping name. Starting Sept. 5, 2006, the cutoff will be 119 gallons or less.

  • OSHA. OSHA calls for several specific toxic and hazardous substances to be marked with a label or sign. The Hazard Communication Standard also requires the identity to be labeled on hazardous chemical containers.

    The Bloodborne Pathogens Standard requires that BIOHAZARD warning labels be affixed to containers of liquid or semi-liquid blood or other potentially infectious materials, contaminated items, and certain wastes containing blood or other potentially infectious materials.

    In addition, OSHA requires employers to place DANGER, CAUTION, and other signs near hazards likely to cause an accident or injury.

  • ANSI Z535.2. The American National Standards Institute's Z535.2, Environmental and Facility Safety Signs, sets standards for DANGER, CAUTION, NOTICE, and other signs for industrial workplaces. ANSI signs are often used to identify hazardous substances in a work area.
  • International. International symbols such as exploding material or corrosive liquid poured on a hand may be found on hazardous substance containers. However, these symbols, while they help to identify the hazard, do not provide the chemical name.
  • Military. Where a military base is near a community, emergency responders should know the U.S. military placarding system for explosives:

    Class 1--Orange octagon for mass detonation.
    Class 2--Orange X for explosion with fragments.
    Class 3--Orange upside-down triangle for mass fire hazard.
    Class 4--Orange diamond for moderate fire hazard.

Other Identification Tools
In addition to markings, emergency responders can use other tools to confirm the identity of a hazardous substance:

  • Shipping Paper. Any bill of lading containing a hazardous material entry or entries for transportation. When hazardous waste is transported, a "manifest" is used. The proper shipping name is included.
  • Material Safety Data Sheet (MSDS). Written or printed document about a hazardous chemical that is sent with the initial shipment of the chemical and the first shipment after an MSDS is updated. The chemical identity is one required element of an MSDS.
  • Guidebooks. One of the most popular guidebooks is the 2004 Emergency Response Guidebook (ERG). This guidebook deciphers the four-digit identification number on transport containers and provides hazard information and emergency procedures. OSHA requires emergency responders to understand how to use the ERG.
  • Other useful guidebooks include the NIOSH Pocket Guide and the Chemical Hazard Response Information System (CHRIS).
  • Databases. Electronic sources can help identify hazardous substances. These include the Registry of Toxic Effects of Chemical Substances, the Occupational Health Guidelines for Chemical Hazards, and databases provided by chemical manufacturers.
  • Hotlines. 24-hour hotline services include CHEMTREC at 800-424-9300, CHEM-TEL at 800-255-3924, and the National Response Center at 800-424-8802.
  • Monitoring. When other identification methods fail, use air monitoring to determine oxygen, flammability, and carbon monoxide levels.
  • Employees. Don't overlook employee knowledge; employees are familiar with the hazardous substances in their workplace.
  • Company Plans. OSHA requires that a written Hazard Communication Program contain a list of hazardous chemicals known to be present at the facility.

Identification Obstacles
Identifying hazardous substances is not always easy, and sometimes it is nearly impossible when faced with the following marking obstacles:

  • Marking Errors. Markings are not always correct. Responders should use several identification methods to verify the identity.
  • Safe Distances. Binoculars can help responders see markings from a safe distance.
  • Smoke/Fog. Responders should use other identification methods when smoke or fog blocks markings from view.
  • Destroyed Markings. Responders should use other identification methods.
  • Missing/Incomplete Markings. Responders should use other identification methods.
  • Multiple Substances. Responders should use caution when they don't know which substance is involved and take action based on the worst-case scenario.
  • Lost/Inaccessible Shipping Papers. Responders can call the manufacturer to fax copies to them.
  • Concealed Hazardous Substances. Responders should watch for the following clues to criminal or terrorist activity: odd odors, unexplained illness, strange-tasting water, missing inventory, broken locks, or suspicious packages or persons.

Emergency responders should not rely completely on only one identification tool to identify a hazardous substance. Instead, they should look at many identification tools where possible. If there is still doubt as to substance identity, responders should get assistance or take a worst-case scenario approach until they know for sure what they are dealing with.

This article appeared in the December 2005 issue of Occupational Health & Safety.

This article originally appeared in the December 2005 issue of Occupational Health & Safety.

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