A mixture of salt and water with a splash of vinegar and a jolt of electrochemical activation is supplying Waco firefighters with a safe but powerful disinfectant as they work to keep their equipment and quarters free of COVID-19.
Crews at Waco Fire Station No. 11, where the department’s hazardous materials unit is housed, have also developed a new spray system for the disinfectant using their air tanks and other common firehouse equipment. Their formula for homemade hypochlorous acid paired with the spray system lets them kill viruses, bacteria and fungus on gear, trucks and high-use firehouse areas in 60 seconds without the need to wipe everything down afterward.
“For lack of a better term, we are the science nerds at Station 11, you know the hazmat crew. Because there is a lot of chemistry that goes into working hazmat calls, we knew we could do something during this time,” said Waco fire Lt. Philip Burnett, who works at Station No. 11. “The mixture is basically water, salt and we have to put vinegar in it to lower the pH level to make it neutral, then basically ‘cook’ it by putting electricity to it to make the acid with a kill-rate higher than bleach.”
Federal agencies have signed off on hypochlorous acid’s use for a variety of disinfectant purposes, including in uses where it comes in direct contact with food during processing.
Local firefighters developed their system based on an idea from the Tulsa Fire Department in Oklahoma, and firehouses around the country have produced and used the disinfectant as they work to keep themselves safe while living in close quarters and regularly interacting with people in need of their help.
“I think this is critically important, specifically in the unknowns of COVID-19, and when you have guys on edge about the risk of exposure,” Waco Fire Chief Gregory Summers said. “This process really puts them at ease, because if they are go on a call where there is a risk of exposure, they know we have the capability of deconning things, including themselves, on things we have to do on a daily basis.”
Crews started with a spraying system made from their self-contained breathing apparatus, but the right disinfectant was needed to make it practical, Lt. Max Breese said. The main piece of equipment that was not already in-house was the electrolysis system needed to produce the hypochlorous acid.
“We originally were just making a bleach solution and spraying things down, but that was tearing stuff up, and one of our battalion chiefs came up with the hypochlorous acid,” Breese said. “It took a little bit of research, figuring out how to make it and test it and although we did have a few errors, we’ve got it down pat now.”
In the past three weeks, Station No. 11 crews have visited each of the 14 fire stations, sprayed gear and bottled solution for each station to decontaminate high-traffic areas. The solution generally does not have a long shelf life, but it has been in high demand, he said.
Summers said the department has used the solution locally and has helped American Medical Response disinfect ambulances after calls. He said the solution has even been sprayed on firefighters after potential exposure to the coronavirus.
“When you look that the hypochlorous acid is about 10 times stronger than bleach as a disinfectant, this speaks volumes as to the issue of cleaning surfaces, facilities and just about anything,” Summers said. “This was a no-brainier for us. … I think it is admirable that we have members that are stepping up to the plate.”