Scientists at the Centre for Atmospheric Science have collaborated with the Defence Science and Technology Laboratory (Dstl) to investigate the potential of ozone in expediting the decontamination process of ambulances, with the aim of potentially enhancing life-saving measures.

The disinfection process for ambulances after transporting a suspected COVID-19 patient can typically consume around 45 minutes. To address a request by the Welsh Ambulance Service, submitted through the Defence and Security Accelerator (DASA), the Defence Science and Technology Laboratory (Dstl) enlisted the assistance of Professor Rod Jones and Dr. Chiara Giorio to conduct ozone testing for the development of a swift sanitization technology.

For numerous years, ozone (O3) has proven to be a highly efficient disinfectant, widely employed in disinfecting rooms, hospital equipment, and even utilized as a chlorine substitute in swimming pools.

In response to the SARS epidemic in 2003, ozone sterilization was successfully employed to purify environments contaminated with SARS-CoV-1. It is believed that ozone will have a similar effect on SARS-CoV-2, the virus responsible for COVID-19, by permeating the protein coat and causing damage to the viral RNA.

“Dstl requires precise devices to assess the ozone concentration in various sections of the ambulance to ensure that ozone has effectively permeated and disinfected all areas,” Giorio explains, emphasizing the necessity of verifying ozone’s thorough reach and sanitization within ambulance interiors.

Giorio and Senior Technical Officer Ray Freshwater were instrumental in providing their assistance in this regard.

Giorio’s research focuses on merging field measurements with laboratory experiments to comprehend the progression of particles in the atmosphere and evaluate their impact on climate and public health. She explains, “Ozone plays a significant role as one of the primary oxidants in the atmosphere and contributes to the generation of secondary aerosol particles. In my research, I employ ozone and other gases to replicate atmospheric reactions that lead to particle formation.”

To facilitate the simulation of these reactions, Giorio possesses an ozone generator. Ollie May, a scientist at Dstl who is currently pursuing a Ph.D. in the Department under Professor Steven Ley, approached Giorio and Jones to utilize this generator in order to assist Dstl in testing the precision of novel enzymatic indicators (EIs) and electrochemical sensors. These testing methods are crucial for determining the extent to which ozone has successfully permeated the interior of an ambulance.

Leveraging the ozone generator in their laboratory, Giorio and Freshwater successfully generated ozone at regulated concentrations within a fume cupboard that housed the indicators and sensors. This setup provided May and his colleagues with a baseline for their testing purposes.

Dstl has additionally conducted trials with one of the Electro Chemical Cell (ECC) boards developed by the Jones group, which has been employed for numerous years to measure atmospheric gases. Freshwater explains, “Through our experience, we have devised methods to simplify the measurements and streamline data compilation, potentially offering a faster pathway for enhancing their measurement capabilities.”

Building upon these initial tests, Dstl researchers proceeded to recreate the interior of an ambulance within a chemical exposure chamber located at Porton Down. Dstl recently disclosed the successful evaluation of 12 technologies, with certain cases demonstrating a reduction in cleaning time from an hour to approximately ten minutes. May acknowledges, “While not explicitly mentioned, Chiara and Ray played a pivotal role in this endeavor.” Giorio expresses her satisfaction, stating, “We are simply delighted that we could offer our assistance.”