Hazardous Materials

Hazardous materials can pass through the city by train or vehicle, run through underground pipelines. They can be stored in large commercial buildings and under kitchen sinks in homes. Know how to prepare and protect yourself from the effects of hazardous materials.

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Household Chemical Emergencies

Nearly every household uses products containing hazardous materials or chemicals. Knowing what these products are and what to do in case of an emergency is extremely important for reducing their risk to homes and individuals.


Fixed Site Incidents

Hazardous material sites are all around us; from chemical manufacturers to service stations, hospitals to hazardous materials waste sites. Most of these products when used and handled properly pose no danger to the public. 

Collin County has a Local Emergency Planning Committee (LEPC) that ensures residents and workers in Collin County are aware and informed of their right to know what chemicals are being stored, used, released and discarded in the county.

Request additional information by completing an Open Records Request at the Collin County Public Information website.


Identification Standards

The National Fire Protection Association 704 (NFPA 704) provides a recognized and understood standard for identifying specific hazards and their severity.

  • Applicable to industrial, commercial and institutional facilities that manufacture, process or store hazardous materials. 
  • Characterized by the diamond, “square-on-point” shape. 
  • Identities the degree of severity for the health, flammability and instability of hazards.
  • Indicates severity by a numerical rating from zero, indicating a minimal hazard, to four, indicating a severe hazard.

Hazard placards should be posted on the two exterior walls of a facility, access to a room or area or each principal means of access to an exterior storage area. Placards provide quick hazard information for first responders and should be visible in case of an emergency near entrances.Hazmat Placard

  • Health is arranged at the nine o’clock position and color-coded blue.
  • Flammability is arranged at the 12 o’clock position and color-coded red.
  • Instability is arranged at the three o’clock position and color-coded yellow.
  • Special hazards are located in the six o’clock position with a white color-coded background. The special hazards in use are W, which indicates unusual reactivity with water, and OX, which indicates that material is an oxidizer.


Transportation Incidents

Hazardous materials are present in many fixed locations, but it is essential that these hazardous materials be transported to other sites and facilities. This means that materials are present on the highways and railroads of the City of McKinney. Most often, these hazardous substances are released as a result of transportation accidents.

Most hazardous materials are required to be shipped in containers that meet strict specifications established by the Department of Transportation (DOT). DOT labels come in the shape of a 4-inch diamond and are used on individual packages, drums or other small containers. DOT placards are also diamond-shaped (square-on-point), but are larger and found on the outside ends of a transport vehicle.

Placards alert public safety agencies and the general public as to the content of containers and allow visual identification of shipments. They are color-coded and contain symbols and numbers that designate the hazard class or division of the hazardous material that is being shipped. For bulk and certain non-bulk shipments, a four-digit hazardous material identification number may be on the placard, an accompanying orange panel, or a white square-on-point sign.

Transportation Placards.jpg

Hazardous materials are categorized into nine classes:

  1. Explosives
  2. Gases
  3. Flammable and combustible liquids
  4. Flammable solids, spontaneously combustible materials and dangerous when wet materials
  5. Oxidizers and organic peroxides
  6. Toxic (poison or poisonous) material and infectious substances
  7. Radioactive materials
  8. Corrosive materials
  9. Miscellaneous dangers goods