The British Standards Institution (BSI) says that A4 size face shields do not always protect the faces of healthcare professionals from exposure to Covid-19.
Faced with a shortage of personal protective equipment (PPE), many communities have started to make their own to help workers on the front lines.
These include 3D printing and laser cutting projects.
Some incorporate A4 size transparent acetate paper, designed for ceiling projectors, to make the visor.
“People are trying to use readily available materials,” said Nathan Shipley, EPP group certification manager at BSI.
“Using acetates from an overhead projector is a quick fix, but the width of the acetate screens isn’t wide enough.
“Some people say, ‘any PPE is better than no PPE’, but if you wear something you think it will protect you and it won’t, you’re more in danger.”
The BSI examines three key areas when testing DPI face shields:
- How clear is the visor to look at
- The size of the headband – to minimize pressure headaches
- The coverage area – how far around the face it is protected from droplets or splashes
The European standard EN166 follows, which determines the size of the face area that needs protection, although some women find that the standard emission kit does not fit them.
BSI said it has so far approved 21 face protection projects and has received around 70 from various groups, including companies, academic institutions and individuals.
It is intended to perform tests within two to three days and, if an EC number is granted, it means that it has passed European safety standards – it is for the duration of the pandemic and not permanent.
Royal Mint and the University of Nottingham were the first to obtain regulatory approval.
“We wanted to make sure we provided something that was safe,” said Professor Richard Hague of the University’s Faculty of Engineering.
The professor. Hague said the process took around 10 days, as the original design also faced the problem of A4 width.
The university is currently delivering 5,000 facial shields to the NHS in Nottingham.
“This is not a difficult thing to do – it is using a system that we have to make a necessary product for,” said prof. Hague.