Exploring a Low-Cost Method for Decontamination of PPE Equipment

Amid the COVID-19 pandemic, personal protection equipment (PPE) has become a necessity. PPE generally refers to protective clothing, helmets, goggles, or other garments or equipment designed to protect the wearer’s body from injury or infection. The hazards addressed by protective equipment include physical, electrical, heat, chemicals, biohazards, and airborne particulate matter.

With the onset of winter, coronavirus cases being reported in the US is increasing, a trend already witnessed in Europe and elsewhere across the globe. At the same time, hospitals and other healthcare institutions are likely to experience supply-chain problems, given the limited supplies of filtering face piece respirators, such as N95 masks. However, strategies to decontaminate personal protective equipment, or PPE, are still a serious issue in many hospitals with limited resources, in many countries.

A solution may be in sight as researchers at the University of Delaware (UD) in the US have devised a process to decontaminate N95 masks in a cost-effective manner. They did by using readily available materials that can be purchased at hardware shops, together with ultraviolet type C (UV-C) lights found in academic research and industrial facilities. This method offers comparable decontamination to more expensive methods at an affordable cost of about $50 (£38) in materials.

In an online interview with Engineering & Technology Magazine, Jason Gleghorn, an associate professor of biomedical engineering at UD said that the team focused on frugal science for this project. The team ‘Frugal Science’ refers to the design, development, and deployment of ultra-affordable yet powerful scientific tools for the masses.

“We focused on frugal science – how do you decontaminate PPE in a very simple way that is easily scalable for high throughput so that any health care facility can use it globally,”

Rachel Gilbert, a doctoral candidate in the Gleghorn Lab noticed that her friends in healthcare were wearing the same N95 masks for days and wondered if there was a way to utilize existing technology to decontaminate such equipment in a cheap yet scalable way. She found that UV-C light which was sometimes being used to sterilisation of various materials and equipment found in research labs could work.

“Being able to provide something that can be on-site, as opposed to other methods that require surgical-suite UV systems costing tens of thousands of dollars or shipping masks out for decontamination and relying on them coming back in a timely manner, was important,” Gilbert explained.

The team modified the household common fluorescent light fixtures to hold and power the specialised UVGI light bulbs. By adding that to specific light placement arrangements and tin foil covered cardboard for reflectors, creates multiple decontamination arrangements people can make.

The researchers did multiple mathematical calculations and modelling to check that the strength of UV radiation given out by the repurposed lights was accurate and that the UV exposure received by N95 masks was sufficient to decontaminate them.

In case you are thinking of setting up your own self-decontamination unit at home, researchers warn against doing so as specialized equipment, including a UV-C-intensity meter and proper safety equipment are required. The latter, which includes proper personal protective equipment, is needed to work with UV light, which can disrupt DNA and pose safety concerns.

The fact that it can disrupt DNA is why it works. UV light can cause the virus DNA to disperse and become ineffective. Although the virus might be attracted to you, the genetic content within will be fragmented and unable to replicate.

Although re-using masks might not be ideal but as not every hospital or other patient care facilities are equipped with enough PPE to meet demand in a crisis, this could be one immediate solution for first-responders. Moving forward, one option would be that academic and research institutions could partner with hospital systems to collaboratively put these off-the-shelf systems in place where they are needed.