What Does Barhole Mean?
A barhole is a small hole dug into soil or pavement near gas pipes. It is used as a method of detecting or locating gas leaks.
The use of barholes is an important part of investigation odor complaints that may be linked to a gas leak. If a leak is detected through the barhole, the hole should not be covered but allowed to vent.
Safeopedia Explains Barhole
When an odor complaint requires an investigation, the first step is to find the surface hotspot. Once it's been located, a combustible gas indicator (CGI) is used to take readings.The CGI is a device capable of detecting and measuring gas concentrations in the air.
When evaluating the gas leak, the perimeter of the leak area should be established. If a building is located within that perimeter, the investigation should continue insue it.
Centering and Pinpointing a Gas Leak
If a gas is detected, the leak has to be centered to determine the spread area in all directions and then pinpointed. A minimum of five barholes in a diamond patter with one barhole at the center should be used. All the barholes should be of the same size and depth, and as far as possible should be up to pipe depth.
If the barholes don't pinpoint the leak, more barholes are dug where the gas reading is at its highest. The process is repeated until the source of the leak has been situated.
For leaks detected near a gas line, the first three barholes should be as close to the gas line as possible.