Gas leak safety during construction: what to do

Construction can expose buried gas mains, service lines and meter connections that were not visible during planning. A leak may follow excavation, boring, trenching, demolition or movement of heavy machinery, and even a small release can create a fire or explosion hazard.

This guidance is useful for residents, contractors and site supervisors in Australia, while also reflecting the safety responsibilities associated with municipal infrastructure in Susanville, California. Gas networks, emergency numbers and utility operators differ by location, so the local gas distributor and emergency services should always take priority.

Treat the smell of rotten eggs, a hissing sound, blowing dust, bubbles in wet ground or dying vegetation near excavation as a possible gas escape. Act promptly, keep people away and avoid doing anything that could produce a spark.

Recognise the warning signs

Natural gas is normally colourless, but an odorant is added to give it a distinctive sulphur-like smell. A leak can also be detected as a steady hiss from a damaged pipe, unexplained bubbling in puddles, disturbed soil or vegetation that appears scorched around a trench.

Do not rely on smell alone. Wind, rain, nearby machinery and temporary loss of smell can hide a release. Construction workers should stop and investigate safely if a trench, boring operation or excavator has contacted an underground service, even when no odour is immediately noticeable.

Stop work and remove ignition sources

Stop excavation, drilling, cutting and vehicle movement as soon as a gas leak is suspected. Warn everyone nearby using clear verbal instructions, but do not operate electrical switches, machinery controls, torches, phones or radios within the suspected gas area. Do not smoke, light a cigarette or start a vehicle.

If it can be done without entering the gas cloud or approaching the damaged line, shut down engines and equipment from a safe distance. Do not attempt to locate the leak more closely, clamp the pipe or cover it with soil. A damaged line can remain dangerous even when the visible release seems small.

Move away and call for help

Evacuate people to a safe location upwind and away from the excavation. Keep clear of pits, drains, basements, sheds and enclosed rooms because gas can collect in low or poorly ventilated spaces. Do not return for tools, pets or vehicles until emergency personnel declare the area safe.

In Australia, call Triple Zero (000) if there is immediate danger, fire, an injury or a risk to the public. Once you are safely away, contact the relevant gas distributor’s emergency line and notify the construction supervisor or site manager. In Susanville, California, use 911 for an urgent emergency and report the incident to the responsible gas utility and City of Susanville Public Works.

If a pipe has been struck

If an excavator or auger hits a gas pipe, the operator should stop immediately and, where safe, leave the equipment without touching anything that may create a spark. Do not restart the machine or drive it through a suspected gas cloud. Workers should move away on foot and keep bystanders from approaching.

A ruptured line may continue releasing gas after machinery stops. Never bury the break, turn a valve unless directed by the gas operator, or assume that closing a nearby service valve has made the site safe. Emergency crews need accurate information about the location, excavation depth, pipe condition and any people who may still be inside the exclusion area.

Protect neighbours and road users

Construction sites beside homes, shops, schools or busy roads need a wider safety response. Establish a cordon from a safe position, ask pedestrians to use another route and prevent vehicles from entering the affected area. Do not use traffic flares or other open flames to manage access.

In Australian cities such as Melbourne, Sydney and Brisbane, dense development means a leak can affect adjoining properties, footpaths and public transport routes quickly. In regional areas, including works near Adelaide or Canberra, a slower emergency response or strong wind can carry gas beyond the immediate excavation. Site managers should give emergency services clear access and follow police, fire and gas-network instructions.

Report the incident properly

Record the time, location, work activity and warning signs observed, but only after everyone is safe. Tell the gas operator whether the line was exposed, struck, isolated or still releasing gas. Provide the street address, nearest intersection and access point, using landmarks that crews can identify quickly.

Australian contractors should arrange underground service information before digging through Before You Dig Australia by calling 1100 or using its online service. This information helps identify registered services, but it does not remove the need for careful potholing, safe excavation practices and attention to unmarked private lines. A Dial Before You Dig response should be kept with the site documentation.

Prevent another gas emergency

Before construction begins, confirm plans, locate services, mark the route on the ground and brief every worker, subcontractor and delivery driver. Use a permit-to-dig process, maintain the required clearance around gas assets and use non-destructive digging where the service location is uncertain. Gas meters, regulators and exposed pipework should remain accessible and protected from impact.

Public infrastructure teams also coordinate works involving roads, footpaths, stormwater, water, natural gas and other services. The Susanville Public Works website provides access to municipal information, utility contacts and service resources relevant to local works. For residents planning excavation or repairs, check the responsible authority before starting and obtain any required permit.

A gas leak can also disrupt meters, appliances and household service, so do not reconnect equipment until the gas operator approves it. Once the site is cleared, inspect the repair area and update the construction risk assessment. Household customers can review practical energy-use guidance in winter gas bill advice, but saving energy must never involve bypassing safety checks or interfering with gas infrastructure.