If you smell gas inside your house, leave now and take everyone with you, pets included. Do not flip a light switch, unplug anything, use a phone inside, press a doorbell, or run the garage door opener. Any of those can throw a spark. Go outside, get well away from the house, and call 911 or your gas utility from out there. If you are on propane, call your propane supplier. Do not go back in until someone qualified tells you it is clear.
Everything below this paragraph is for after you are outside, or for a day when you are not smelling anything and just want to understand the problem. If you can smell gas right now, stop reading and go.
This guide covers what a gas leak smells like, how to tell you really have one, why a carbon monoxide detector will not warn you about it, whether an older house is more likely to leak, and what the plumber's job is once the utility has made things safe.
What a Gas Leak Smells Like
Natural gas has no smell of its own. Utilities add an odorant so that a leak announces itself, and the result is a sulfur smell that most people describe as rotten eggs. Some describe it as a burnt match, or a sharp, skunky note. Propane is odorized the same way, and it can smell a little more oily or garlicky to some noses.
The strength changes with how much is escaping and how much air is moving. A small leak behind a stove can read as a faint whiff that comes and goes. A bigger one fills a room. Your nose also tires out. After a few minutes in a gassy room you may stop noticing it, which is exactly the wrong moment to decide it was nothing.
So the rule is simple. If the smell is in the air indoors, treat it as gas until a professional says otherwise. A false alarm costs you a few minutes standing in the yard. Staying put when it is real can cost far more.
How You Know You Have a Leak and Not Something Else
From outside, with the house cleared, the signs that point to a real leak are the smell itself, a hissing or whistling sound near a pipe or the meter, dead or yellowing patches of grass over a buried line, bubbling in standing water near the meter, and a gas bill that jumped for no reason you can name. Dizziness, headache, and nausea inside the house can also go with a gas problem, and you should treat them seriously.
A few things get mistaken for gas. A rotten egg smell that shows up only at the hot tap, with nothing in the air, is usually a reaction inside the water heater tank and not a gas leak. Sewer gas from a dry drain trap smells different, more like waste than sulfur. A new appliance can also give off a burnt, dusty smell the first few times it runs.
You should not try to sort these out yourself while you are standing in a gassy kitchen. The testing that actually confirms a leak is a pressure test of the piping, and that is done after the area is safe. Your job is to recognize the smell and get out. The confirming comes later.
Will a Carbon Monoxide Detector Catch It?
No. A carbon monoxide detector senses carbon monoxide, which is a product of incomplete burning, not raw natural gas. A house can fill with unburned gas and the CO detector will sit there silent, because there is no carbon monoxide to sense.
There are explosive gas detectors that sense natural gas or propane. Some combination units do both jobs, but you have to read the label to know what yours actually detects. A plain CO alarm does not do it. Keep your CO detectors, because carbon monoxide is its own serious hazard, but do not treat them as gas leak protection.
Carbon monoxide shows up here for reasons that have nothing to do with a leaking pipe. After Winter Storm Uri, people ran ovens, generators, and grills indoors or in garages for heat, and that is how carbon monoxide builds up. Generators belong outdoors and well away from windows and doors. A gas oven is not a heater. If a CO alarm sounds, the response is the same as for gas: get everyone out into fresh air and call for help.
Are Older Houses More Prone to Gas Leaks?
They tend to be, for ordinary reasons. Older homes in Beaumont, Port Arthur, Nederland, and Orange often still carry original black iron gas pipe with threaded joints, and old shutoff valves that have not been turned in decades. Metal corrodes, threads loosen, and valves weep at the stem. Appliances get swapped over the years, and flexible connectors that were never meant to last forever get reused or stretched.
Soil matters too. The Gulf Coast clay under our slabs and yards swells when it is wet and shrinks when it is dry. That movement stresses buried gas lines running from the meter to the house, and a line that has flexed for decades is more likely to fail at a fitting. A newer house is not immune, since a poorly made joint can leak on day one, but age and ground movement are the usual causes here.
None of this means an old house is unsafe. It means the gas piping deserves a look when you buy, when you add an appliance, or when anything smells off.
Floods, Freezes, and Relit Pilots
Southeast Texas storms leave a trail of gas problems. After Harvey and Imelda, water got into meters, regulators, and appliance controls in homes across Jefferson, Orange, and Hardin counties. A gas water heater, furnace, range, or dryer that sat in floodwater should be inspected before it is lit again, even if it looks fine. Controls that took on water can fail in ways you cannot see.
Freezes bring a different pattern. When Uri hit, pilot lights went out and people relit appliances they had not touched in years. If a pilot will not stay lit, or you smell gas while trying to relight one, stop. Do not keep trying with a lighter. Leave and call.
After any event that disturbed your gas system, a pressure test before service is restored is the standard way to know the piping is tight.
What the Utility Does and What the Plumber Does
The gas utility's emergency crew comes for the smell. They check the area with detection equipment and can shut off service at the meter. Their work is making the property safe, and they generally do not repair the piping on the house side of the meter.
That piping is the plumber's job. In Texas, plumbers are licensed by the TSBPE, and gas piping inside the home is licensed plumbing work. The repair starts by pressure testing the system to confirm a leak and see how fast it loses pressure. Then the likely spots get checked first: appliance connectors, threaded joints, old valves, and the point where the line enters the house. The fix might be a new connector or a replaced section of buried line.
Before anything is turned back on, the system gets tested again under pressure. A gas repair is not finished until it holds. N-Sink is open 24 hours, seven days a week, so once the utility has cleared the house, the repair does not have to wait for morning.
