ObDIY face maskis really effective against viruses is a very controversial topic. Researchers and doctors basically agree: self-sewn fabric masks offer little, if any, protection against pathogens. The reusable face mask cannot filter them. Recently, however, an idea has taken hold: Could a breathing mask with a HEPA filter help in the fight against coronavirus? We take a closer look at the question and explain how you can make a respirator mask with a filter for repeated use yourself.
Breathing mask with Hepa filter: Can it really filter aerosols from the air?
The medical professionals wear two types of protective masks. The first is a disposable breathing mask called an N95. It can filter up to 95% of aerosols from the air and therefore retains over 99% of pathogens. However, this mask is only intended for doctors and hospital staff. It is only an effective protective measure if it is worn correctly and completely covers the mouth and nose. This face mask is worn during epidemics, such as the swine flu epidemic a few years ago.
Diesecond breathing maskis the so-called surgical protective mask. It is worn by surgeons during operations to prevent smear and droplet infections and to protect the patient from viruses and bacteria. If worn correctly, this face mask can also hold back the majority of pathogens.
The two types of face masks are intended exclusively for medical personnel. That's why it's important that the population doesn't buy up the respiratory masks. Unless the local authorities recommend otherwise, everyone can make their own face mask. You can wear a cloth maskfrom household itemslike sewing an old T-shirt or bed linen yourself. In comparison, it only offers limited protection, if any. That's why most people look for a filter for their respirators. Kitchen paper and dry wet wipes are recommended as filters. However, there are no studies that can really confirm their protective effect.
That's why you ask yourself whether a HEPA filter is effectiveagainst virusesand could protect bacteria. But what actually is a HEPA filter? It is a particulate filter that can effectively filter even small particles from the air. A HEPA filter was developed to filter pollen, dust and mites and keep them in the vacuum cleaner. At the same time, the filters allow air to pass through. This means that they are practically permeable to air and that, theoretically, people can breathe through them. According to the EU standard 1822-1:1998, HEPA filters have been divided into several classes depending on how well they can filter the air. Meanwhile, the EU standard was changed in 2009. Any filter that filters 99.98% of the air is called HEPA. All filters that filter the air up to 99.97% are called EPA. Anyone ordering such filters from the USA should make sure that they comply with Mil Std. 292.
Breathing mask with HEPA filter: What types of HEPA filters are sold?
There are several classes of filters that comply with the EU standard 1822, the DIN standard 24183 and the USA standard Mil. Hours 292 correspond. We give you an overview:
- Filters that are able to filter up to 85% of fine dust are referred to as EU 10 or H 10. These filters are not sold in the USA.
- EU 11 and H 11 are filters that filter over 95% of fine particles from the air. In the USA they are only called “95%”.
- EU 12 or H 12 filters also comply with the standard and can filter up to 99.97% effective fine particles from the air.
- EU13 / H 13 and EU 14 / H 14 are HEPA filters that can filter over 99.99 of fine particles, mites and dirt from the air. These filters are usually recommended for allergy sufferers.
Theoretically, HEPA filters could remove the smallest corona particles from the air, although there are currently no studies that could prove this. It remains unclear whether such a mask really effectively cleans the air. But at least it filters the air betteras a cloth mask.
It also remains unclear whether breathing through HEPA filters is safe for health. However, since these filters are installed in vacuum cleaners and are recommended for allergy sufferers, one could assume that they improve air quality and that they cannot harm your health.
Anyone who would like to make a face mask with a HEPA filter themselves should always seek advice from the local health authorities or their family doctor.
Children and babiesshould never wear homemade face masks! As a rule, babies are not allowed to wear a face mask anyway because they pose a risk of suffocation.
Make your own breathing mask with a HEPA filter: instructions
It is very easy to make a breathing mask with a HEPA filter yourself. Buy a filter EU 13 or EU 14 filter, cut off its ends and take out the fabric from the filter. There are three traces of hot glue holding the individual HEPA fabric sheets together. Remove them carefully, being careful not to tear or damage the fabric. Cut out a rectangle measuring 15cm x 20cm. Now place four evenly spaced folds in the same direction with a width of 1 cm and stitch them in place. The filter is ready and you can put it into a cloth mask.
You can fix the folds with clothespins
And then stitch the finished filter in place
