Who do I call first if I smell a gas leak in my house?

Evacuate the property immediately. Do not touch light switches, do not use phones indoors, and do not start cars in the garage. Call 911 and your natural gas utility (Southwest Gas) from a safe distance outside.

What equipment is used to find gas leaks?

Licensed technicians use sensitive electronic combustible gas indicators (CGIs) with flexible gooseneck sniffer probes capable of measuring parts-per-million (PPM) concentrations, alongside digital manometer pressure decay gauges that certify whether a line holds pressure.

Does the gas utility fix interior gas leaks?

No. The gas utility will red-tag and lock out your gas meter for safety if they detect a leak downstream of the meter. The property owner must hire an independent licensed plumbing/gas contractor to locate, repair, and pressure-test the piping before the utility will restore service.

Gas Leak Detection in North Mountain Village, Phoenix

CRITICAL SAFETY NOTICE: If you smell a sulfur or rotten-egg odor, evacuate all occupants and pets immediately! Do NOT turn electrical switches on or off, do NOT light flames, and do NOT use phones inside. Call 911 and your gas utility (Southwest Gas) from outdoors.

Technician testing gas appliance line joints with a digital combustible gas sniffer probe meter — Precision combustible gas detector probe identifying parts-per-million (PPM) trace emissions around manifold unions.

Signs of an active natural gas or propane leak

Natural gas is naturally odorless; utilities inject a harmless chemical called mercaptan to give it an unmistakable sulfur / rotten-egg scent. Key warnings include:

Rotten-egg or sulfur smell: Even faint intermittent whiffs near water heaters, furnaces, or kitchen ranges.
Audible hissing or whistling: High-pressure gas escaping threaded pipe joints or flexible appliance connectors.
Dead or discolored vegetation: A localized patch of brown lawn or dying plants along an underground exterior yard gas line.
Continuous bubbling: Bubbles surfacing in puddles or standing rain water above buried gas service lines.

Advanced technologies used for gas leak detection

Once initial emergency responders clear the scene or lock out the gas meter, independent licensed contractors employ precision diagnostic instruments:

Sensor Probe

Combustible Gas Indicators (CGI Sniffers)

Solid-state and catalytic bead sensors detect trace concentrations of hydrocarbon gases as low as 10 to 50 PPM, alerting technicians with escalating acoustic clicks and visual LED readouts.

Pressure Integrity

Digital Manometer Pressure Decay

Technicians pressurize isolated gas systems with inert air to specific test pressures (e.g., 3 to 15 PSI) while logging the decay rate over 15 to 30 minutes to verify whether the entire run is hermetically tight.

Ultrasonics

Ultrasonic Airborne Acoustic Detectors

Translates high-frequency turbulence created by high-pressure gas passing through a microscopic orifice into human-audible frequencies via noise-canceling headsets.

What happens after the gas utility locks your meter?

When Southwest Gas or the local utility responds to an emergency call, they shut off and lock the meter with a "red tag" to safeguard the structure. They will not rebuild or service interior customer piping. An independent licensed plumbing/gas contractor must:

Isolate the piping branches and diagnose the exact fitting or pipe rupture.
Replace damaged black iron, CSST, or poly piping according to Phoenix residential building codes.
Perform an official pressure test that passes municipal inspection.
Coordinate with the utility to unlock and restore gas service safely.

Difference between water and gas leaks

Gas leaks are an imminent explosion and inhalation hazard, requiring specialized gas certifications. If your symptoms involve water accumulation, damp flooring, or foundation concerns, explore our guide to water leak detection and slab leak detection.

Need post-emergency gas line diagnostics?

Connect with an independent local gas line specialist in North Mountain Village, Phoenix.

Call for Local Help: (602) 836-3562

Frequently asked questions

Who do I call first if I smell gas?

Evacuate everyone from the building immediately and dial 911 and your natural gas provider (Southwest Gas) from outdoors.

Can a referral service fix a gas leak directly?

No. Leak Detection Pro is a referral network connecting callers with independent, ROC-licensed gas and plumbing specialists after the initial emergency is secured.

How long does a gas line pressure test take?

A standard gas line pressure test typically requires 15 to 30 minutes of monitored gauge hold time once the system has been pressurized with air.