A portable multi-gas sensor checks for methane in a manhole before the cover is opened.

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Multi-gas sensors used for confined space entry (especially when associated with sewers) are typically intended to check for the presence of methane (explosive hazard), carbon monoxide (poison), and hydrogen sulfide (poison). Methane is generally present at the top of a space, and could cause an explosion if opening the space causes a spark. Carbon monoxide is present at mid-height, and hydrogen sulfide is heavier than air and sits at the bottom. Gas meters often come with pumps and rubber tubing in order to pump gases from lower down in the space without anyone having to enter.

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Size: 4750px × 3563px
Location: Canada
Photo credit: © Alexander McClearn / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: carbon, confined, cover, danger, entry, explosion, explosive, frame, gas, hole, holes, hydrogen, manhole, meter, methane, monitor, monoxide, multi, safety, sensor, space, sulfide, sulphide