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Published on: February 23, 2020
Self-activating air filtration device for aerosol control during luminal instruments drying in the sterile processing
Wei Zheng1, Ying He2, Ping Gui1
1Sterile Processing Department, Sichuan Clinical Research Center for Cancer, Sichuan Cancer Hospital &Institute, Sichuan Cancer Center, Affiliated Cancer Hospital of University of Electronic Science and Technology of China, Chengdu, China.
Background:
Luminal instruments are characterized by their slender internal lumens, which make them particularly challenging to clean and dry. A common drying method used by Sterile Processing Department (SPD) technicians involves blowing high-pressure air into one end of the lumen to expel moisture. However, this process generates a significant amount of aerosols that may contain bacteria, viruses, and other microorganisms. These aerosols can increase the microbial load in the SPD environment, leading to secondary contamination of other medical devices and posing health risks to SPD staff. Current methods used in SPD to reduce aerosols, such as gauze pockets and perforated boxes, have shown limited effectiveness.
Methods:
This study designed and fabricated a self-activating air filtration device, which primarily consists of four components: a centrifugal fan, a high-efficiency air filter, an acrylic box, and a diffuse reflective photoelectric switch. The total cost of the device is approximately $25. To verify the functionality of the device, we selected 20 sets of endoscopic instrument packs, 40 suction tubes, and 20 plastic hoses. The device's efficacy in reducing airborne dust particles and biological aerosols was evaluated, and a simple smoke test was conducted to assess its reliability.
Results:
Compared to results obtained without a HEPA filter, the self-activating air filtration device achieved a substantial reduction in airborne dust particles across various sizes: 79.34% for 0.3μm, 78.66% for 0.5μm, 76.58% for 1.0μm, 76.15% for 2.5μm, 72.55% for 5.0μm, and 75.00% for 10μm particles, with an average reduction of 76.36% (calculated using the median). No bacterial growth was observed on the ten culture plates sampled using the device, whereas five out of the ten culture plates sampled without the HEPA filter exhibited bacterial growth, resulting in a positivity rate of 50%. The differences were statistically significant. Additionally, the smoke test confirmed that the device effectively prevented contaminated air from escaping through the top opening of the acrylic box.
Conclusion:
The self-activating air filtration device significantly reduces the aerosols generated during the drying of luminal instruments, thereby mitigating the risks that aerosols pose to both the environment and staff health. Its automatic on-off functionality and low cost of use and maintenance make it a valuable solution for aerosol control in SPD and other hospital settings.
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