What does a natural gas leak smell like?
A natural gas leak doesn't always have the expected sulfur scent, sometimes smelling fishy or like a rotting animal instead. This confusion over the odor's properties, combined with dismissive roommates or the fear of an embarrassing false alarm, causes people to dangerously delay calling 911 or wait until morning to address leaking valves.
What the numbers show
Counted from the threads quoted below. How we count
- This comes up 22.2× more often in r/HomeMaintenance than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
What does a natural gas leak smell like?
- 1Shutting off the gas valve just in case.Did this help you?
- 2Shutting the doors to the room and opening windows.Did this help you?
- 3Calling the fire department to inspect the home.Did this help you?
- 4Turning off the local valve and waiting until the next morning.Did this help you?
- 5Asking roommates or internet forums to determine if the situation is dangerous.Did this help you?
- 6Opening windows and setting up box fans to air out the space (which professionals warn is dangerous).Did this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“My whole house smells like gas and in the basement, the pressure valve for to the heater is leaking. I am not sure if this is an emergency or not because everyone I live with doesn’t seem to care very much and are saying to just check in the morning. but I am pretty concerned.”source ↗
“Don’t worry if it’s a false alarm, I had a false alarm and was so embarrassed.”source ↗
“We smelled gas in our house about 15 years and called 911, they told us to leave the house and the fire department came , took a reading and opened all of the windows for about an hour then rechecked for a reading or any more smell of gas and then couldn’t find any issue after their initial reading.”source ↗
“since finishing the work the room has smelled like a rotting animal/almost fishy in a way.”source ↗
“it does not smell like that sulfur smell I know to be natural gas, but still, seems suspicious?”source ↗
“does this sound like gas? does gas change in its smell properties as it gets more concentrated?”source ↗
Where this came up
People with this problem also raised
- 6Why is there a raw fuel smell and rough idle when stopped?
- 2Strong gas smell in room after new pipe installation
- 41Why is there a mystery wet dog or sour smell in the house?
- 2Why does only the hot water smell like sulfur?
- 2Why does my new mini split smell weird?
- 10Sewer smell in bathroom but can't find the source