The nose knows, the good, bad, delightful and foul. Sometimes our senses are our best detection devices, but as busy humans, we’ve also been known to detect an odd smell, briefly comment on it, cover our nose with our hand and keep moving. Why does natural gas smell like rotten eggs? On March 18th, 1937, the New London School explosion occurred when a natural gas leak caused an explosion, tragically killing 300 students and teachers and destroyed the London School in New London, Texas. Natural gas is invisible and odorless, meaning a gas leak at the school, due to a faulty gas connection, went unnoticed and undetected. At 3:17 p.m. that day, an instructor turned on an electric sander, and it’s believed that the sander's switch caused a spark resulting in the gas-filled air to explode. The Texas State Legislature granted the Texas Railroad Commission regulatory authority to adopt and enforce regulations to add an odor to natural gas to prevent future disasters. Within weeks of the explosion, thiol, also known as mercaptan, an odorous sulfur compound, was added to natural gas to hopefully prevent future deaths and disasters from happening.

Brian Weisker, president of Piedmont Natural Gas, a subsidiary of Duke Energy, says “Train your nose. It’s important to train your nose to recognize the odor of mercaptan. Foul odors like rotten eggs serve as a warning that something is wrong, and knowing the warning signs is the best way to ensure the safety of our customers and communities if a natural gas leak occurs.” 

If you smell mercaptan, leave the property immediately, call 911 from an offsite safe distance and don’t return until you have the all clear from emergency personnel. Another layer of natural gas safety is installing a natural gas detector to keep you and your staff aware of potential leaks. A natural gas detector will sound an alarm if levels of natural gas in the area indicate a leak. Natural gas is lighter than air and rises so it’s extremely important that placement of these alarms is at the right height and coverage area.

Your nose may fail you, but the explosive gas alarm is for your ears, just like a smoke detector. If you have any questions about detecting mercaptan or explosive gas alarms, please contact your gas company for assistance.