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What does PHMSA say odorized natural gas smells like?

Rotten eggs.

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  1. Rotten eggs ✔
  2. Fresh paint
  3. Burnt toast

Why: PHMSA describes a rotten egg smell of odorized natural gas. Natural gas itself has no smell, so utilities add the odor so leaks are noticed.

Huh, didn't know that: PHMSA also lists a hissing or roaring sound and dead vegetation as possible signs of a leak.

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Why shouldn't you argue with a skunk? It'll cause a stink.
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References

Answer: Rotten eggs. PHMSA describes a rotten egg smell of odorized natural gas. Natural gas itself has no smell, so utilities add the odor so leaks are noticed.

  1. PHMSA: Recognizing and Responding to Pipeline Emergencies primis.phmsa.dot.gov/stakeholder-comms/emergencyresponse
    "rotten egg" smell of odorized natural gas
    Checked 2026-10-10.

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