By Kim Hilsenbeck
Following his instincts, and his nose, Emergency Services District 8/Buda Fire Chief Clay Huckaby pinpointed the source of a noxious odor in the Leisure Woods neighborhood.
“We had eight calls yesterday and two this morning come in about the smell of propane or natural gas,” he said in a phone interview Tuesday afternoon.
The calls came from three different neighborhoods — Leisure Woods, Coves of Cimarron and Oxbow Trail — at all times of the day. Strong winds carried the harsh scent across several miles.
Tracking it down was no easy task, but Huckaby plotted the addresses of the calls on a Google map.
“Then we started in Leisure Woods and walked house to house,” he said.
He initially thought the odor was from propane — or more accurately, the chemical ethyl mercaptan, which is commonly added to propane and natural gas since they have no smell. Huckaby knew it wasn’t natural gas as there are no lines or underground sources in those neighborhoods.
His map showed four calls coming from a cluster of streets in Leisure Woods.
“We started on Caracara and fortunately only had to go a few houses,” he said.
The fire crew found the house from which the smell emanated in the 300 block of Dunlin.
“Turns out a homeowner had mixed ethyl mercaptan — a hazardous substance — with mosquito repellent in tiki torches around the backyard,” Huckaby said.
He contacted the Hays Emergency Management Office and a HAZ-MAT crew from the San Marcos Fire Department was dispatched to the home.
A litmus test confirmed the substance was ethyl mercaptan.
“It registered at 300 parts per million,” Huckaby said.
Only an older female was home at the time the Buda fire crew arrived; her husband came home some time later. That homeowner was the person who added the chemical to the tiki torches, telling fire fighters he added something to the torches to get rid of the smell of the mosquito repellent.
Huckaby said questioning by the HAZ-MAT team revealed the homeowner could not explain where he obtained the substance. The man told firefighters he has lived at that address for about 10 years.
In addition to heavy winds, Huckaby said temperatures on Monday could have created a dangerous situation.
According to the Centers for Disease Control, the boiling point of ethyl mercaptan is 95 degrees Fahrenheit. The liquid turns into a gas once it hits that 95-degree mark.
“At 95 degrees,” Huckaby said, “it starts reacting and off-gassing,” which means producing vapors.
Huckaby confirmed it could ignite, particularly since the homeowner left the candles burning in the tiki torches.
Additionally, all of his crew experienced headaches — listed as one of several symptoms of short-term exposure to the mercaptan. One firefighter also vomited, which is another symptom of exposure in humans.
According to Hucakby, the Hays County Environmental Health department, which is now part of the Hays County Sheriff’s Office, was also on site during Tuesday’s incident.
