Hazardous Materials can be identified by seven characteristics. These include:

• Container Shapes - The shape and characteristics of containers can provide clues to their contents. Identifying the specific container can narrow or specifically indicate its contents and the nature of the shipment.
  
• Markings and Colors - Identification markings and colors in combination with the container shape enable easy identification of the contents of a container. 
  
• Labels and Placards - Labels and placards convey information through use of colors and symbols, and are placed on hazardous materials containers to facilitate the identification of their contents.
  
• Shipping Papers/Facility Documents - Shipping papers and facility documents identify contents and may provide information about the safety considerations and health effects of a hazardous material.
  
• Senses - Senses include sight, smell, hearing, touch, taste, and sensations such as skin, eye, or respiratory irritation, etc. Sense are frequently the clue that provides an initial indication of a hazardous materials accident or incident. Typically, the use of the senses should be avoided as a clue beyond the initial or inadvertent stage of identification.
  
• Technology - This is accomplished through the use of electronic monitors and the use of various detectors. Examples of such instruments and materials include:

• Oxygen sensors
• Carbon monoxide sensors
• Combustible gas sensors
• pH paper
• Colorimetric detector tubes
• Other types of sampling and monitoring equipment
  
• Occupancy and Location - The location of the hazardous material accident or incident in relation to the activities that take place at or occupy the area may present a direct clue to the hazardous materials identity. For example, if a green cloud begins forming at a chemical plant that manufacturers chlorine, there is a good chance that the cloud is being caused by a release of chlorine.