For your safety, markers are used to show the approximate location of pipelines and identify the companies that operate them. You should be aware of any pipeline markers in and around your neighborhood. Write down the name and phone number of the pipeline company that is listed on the markers and call in case of an emergency.
Examples of Liquid Petroleum Gas and Highly Volatile and Hazardous Liquids Emergencies
By sight: A pool of liquid on the ground near a pipeline, a dense white cloud of fog over a pipeline, or discolored vegetation surrounding the pipeline may be signs of a leak. As propane, ethane, butane and isobutane vaporize from a liquid state, each produces a heavier-than-air vapor. Therefore, when leaking, the vapor tends to spread along the ground. The cold vapors condense water vapor from the air and create a visible fog, which gives an indication of the area covered by the leaking gas; however, ignitable mixtures extend beyond the area of visible fog.
As natural gasoline leaks, heavier-than-air vapors are produced and spread along the ground. The gasoline vapors are not cold enough to cause a visible fog, but heavy vapor production is sometimes visible; it might look like heat waves.
By sound: An unusual noise, like a hissing or roaring sound, coming from the pipeline might be a sign of a leak.
By smell: An unusual smell may accompany a pipeline leak.