Emergency Guide

Pipeline Safety

Pipeline fire



There is an underground network of pipes carrying a variety of petroleum products including natural gas. Since pipelines are buried underground, line markers like the ones shown here are used to indicate their approximate location along the route. The markers can be found where a pipeline intersects a street, highway or railroad.

The markers display the material transported in the line, the name of the pipeline operator, and a telephone number where the operator can be reached in the event of an emergency.

Pipeline Markers

Are markers always placed on top of the pipeline?

Markers indicate the general location of a pipeline. They cannot be relied upon to indicate the exact position of the pipeline they mark. Also, the pipeline may not follow a straight course between markers. And, while markers are helpful in locating pipelines, they are limited in the information they provide. They provide no information, for example, on the depth or number of pipelines in the vicinity.

Province of Ontario's ONE-CALL!


Ontario One Call




Call Before You Dig - It's the law. Contractors and homeowners are legally required to know the location of buried natural gas pipes before breaking ground and should use the One-Call before starting any digging projects on or near any pipelines. These projects include fences, flagpoles, landscaping, storage buildings, foundations, swimming pools, ground clearing, deep plowing, laying underground pipe or wiring, or any other "digging" projects.

Call and let them know:
-Who is digging  
-When and where you are digging  
-Why and how you plan to dig  

How can you recognize a pipeline leak?

Sight, sound and smell are helpful in detecting pipeline leaks.

    Look for:

    • Crude oil or liquid petroleum products on the ground.
    • A dense white cloud or fog.
    • A spot of dead vegetation in an otherwise green location may indicate a slow leak.
    • Flames (if the leak has ignited).

    Listen for:

    • A roaring or hissing sound.

    Smell for:

    • A pungent odour, sometimes like "rotten eggs".
    • A gasoline-type odour.

What should you do if you suspect a leak?

Your first concern should be for your personal safety and that of those around you.

  • Leave the leak area immediately .
  • Avoid driving into vapour clouds.
  • Avoid direct contact with the escaping gas or liquids.
  • Avoid creating sparks or other sources of heat which could cause the escaping liquids or vapour to ignite and burn. If you find yourself in an area where you suspect hydrocarbon vapours are present, do not light a match, start an engine or even switch on an electric light.
  • Call 9-1-1.
  • Notify the pipeline operator.

    Pipeline contents can vary greatly.

    • Pipelines carry both gaseous and liquid materials.
    • Many liquids form gaseous vapour clouds when released.
    • Many pipelines contain colourless and odourless products.
    • Some pipeline gases are lighter than air and will rise.
    • Other heavier-than-air gases and liquids will stay near the ground and collect in low spots.
    • All petroleum gases and liquids are flammable.
    • Any pipeline leak can be potentially dangerous.