Over the last 20 years, an increasing body of scientific research has provided increasing evidence that firefighting causes an elevated risk of certain types of cancer. In 2021, one study supported by NIOSH showed significantly elevated levels in firefighters of Polycyclic Aromatic Hydrocarbons (PAHs), a highly carcinogenic product of combustion, when measured directly after structural fires (https://pubmed.ncbi.nlm.nih.gov/33654270/).
Products of combustion can become trapped inside the layers of turnout gear. Without timely and effective cleaning, smoke deposits, condensed residues and lingering hydrocarbons in grease, soot, and oil may not only reduce the protective properties of the clothing but put firefighters at risk of secondary exposure to carcinogenic products of combustion after firefighting operations are completed.
While effective in removing a substantial amount of contaminants, infrequent, conventional water-based cleaning of fire PPE cannot thoroughly penetrate & remove 100% of all contaminants from all layers of protective fabric. The residual PAHs embedded in the fabric create a risk of exposing firefighters to these contaminants through inhalation and/or dermal absorption (unlike some chemicals, PAHs in particular have a high rate of dermal absorption) if they become released from the clothing while wearing.
Laundry operations in the fire service have thus far been built upon an assumption that water-based cleaning is the most appropriate process for achieving cleanliness. The 2020 edition of the NFPA 1851 Standard was updated to include cleaning requirements for ISP verification. One of those requirements was a minimum of a 50% average reduction in PAHs, which are known carcinogenic chemicals found at typical structural fires. The average reduction of PAH contamination by standard water washing, following NFPA 1851 guidelines, is between 50%-55%. Until now, there has not been a solution for removing all but a small percentage of PAHs and volatile organic compounds (VOCs) while not using large amounts of water and energy.
What is CO2 Cleaning and How Does it Work?
Liquid carbon dioxide (LCO2) outperforms water on multiple fronts.
• Cleans more Thoroughly – LCO2 ensures a deeper clean without the use of harsh chemicals, allowing for garments to experience less agitation and fiber disruption for a longer-lasting product.
• Saves Natural Resources and Conserves Energy – By eliminating the use of water and heat, CO2 cleaning drastically reduces the consumption of natural resources and energy, allowing for a more sustainable process that prioritizes the environment
• Lowers Carbon Footprint – By utilizing liquid CO2 via a closed-loop cleaning process, we can contribute to a circular economy that effectively reduces the carbon footprint associated with the creation and release of carbon emissions.
How does a CO2 washing machine work? The simple explanation is this: CO2 cleaning leverages CO2’s natural affinity for common contaminants found on and in turnout gear. The pressure in the machine is raised, first by injecting gaseous CO2, then liquid CO2. The pressurized CO2 molecules are significantly smaller than a water molecule, allowing them to easily penetrate all layers of turnout gear, lifting these contaminants up and out of the garment. These particulates are then transported to a sludge tank in the machine from where it’s removed and disposed of as a hazardous waste. Because the process does not use water, garments come out of the machine dry.