PRECIMASK® are high-performance, durable face masks aiming to bring a two-fold solution : protect the wearer and his environment against all forms of aerosols and bacterial particles while reducing the environmental impact of disposable respiratory protective devices.
The use of masks with an appropriate protection level remains as one of the most efficient ways to fight against the spread of the Covid-19 virus and the sanitary crisis it generates. The Precimask® are high performance and durable face masks aiming to bring a two-fold solution: provide an effective contribution to barrier gestures and reduce the environmental impact of protection devices. Furthermore, the very long shelf life of Precimask® solves the issues related to the management of safety stocks for protective masks.
SARS-COV2, the coronavirus responsible for COVID-19 is 0,125 µm in size, or 1/10 micron (1 micron is a 1/1000th of a millimeter).
However, the virus does not circulate alone, but in aerosol droplets or secretions released by the individual. These droplets have typical size in the range of 5 to 10 µm, and down to 3 µm for the smallest ones. The latter tend to remain suspended in the air for a longer time and are hence the most contagious. As a consequence, the masks recommended to fight against the spread of COVID-19 have their filtration efficiency evaluated for aerosols of 3 µm.
UNS masks are a category of masks created especially for the COVID-19 pandemic emergency in march 2020. They do not require approval, but only an evaluation of the filtration efficiency and breathability requirements by a competent laboratory (ref. DGE site : https://www.entreprises.gouv.fr/fr/covid-19/entreprises-comment-faire-tester-masques). In Europe, guidelines for face masks are provided by the document CEN Workshop agreement CWA17553 – Community face coverings, June 2020.
UNS 1 masks must stop 90% of 3 µm particles. Their tightness (or leak rate) is not specified. Most of these masks are constructed with cloth or fabric and can be washed and reused a certain number of times. Successive washes result in a degradation of the filtration efficiency of these masks.
Particle filtrtation rate (>3µm)
|Sports mask (UNS1)||90%|
Since february 2021, a new specification for sports masks has emerged. In comparison with conventional UNS1 masks, the sports masks has the same filtration rate and also uses a filter made of textile material. However, it may have solid parts that allow it to be more airtight and provide better head support. its air permeability is also three times greater than UNS1 masks to allow for optimal breathing at effort.
Surgical masks (ref. Standard NF EN 14683 AC) are masks intended for the sick to prevent them from infecting other people, or traditionally for health professionals to prevent contamination of patients in medical environment. They are flexible and inexpensive to buy but must be discarded after 4 hours of wearing. Depending on their type, they must stop up to 95% of 3 µm particles. Their air-tightness level is not standardized or specified.
Particles filtration rate (>3µm)
|Type II R||liquid resistant Type II|
FFP masks (ref. Standard NF EN 149) are masks intended for healthy people to protect them from sick people. They must filter aerosols with an average size of 0.6 µm and have a standardized leak rate of up to 22% for type FFP1. These soft masks are expensive and should also be discarded after 4 hours of use. In addition, their effectiveness is no longer guaranteed if they are wet or dirty.
Particle filtration rate (>0,6µm)
FMP masks (ref. Standard EN 1827) are rigid masks intended to protect the wearer against environments containing dust, smoke and other toxic and harmful aerosols. These masks are typically used in the chemical industries. They are the only ones equipped with disposable filters and a washable and reusable seal. Their flexible seal provides excellent air tightness. However, these are heavy and expensive equipment and offers low breathability.
FMP mask cartridges (ref. EN 143) must filter two types of aerosols, one with an average size of 0.4 µm and the other with an average size of 0.6 µm.
Particle filtration rate (>0,6µm)
With such a small virus size, almost no mask can stop it. However, the FFP3 and FMP3 masks should still be able to achieve a good level of filtration for this particle size.
These droplets are between 5 μm and 10 μm in diameter and can therefore be stopped by most of the masks described above depending on their filtration efficiency and air tightness.
However, although the fabric of surgical and UNS1 masks can filter droplets containing SARS-COV2, their limited air tightness does not guarantee optimal protection. On the other hand, FFP and FMP masks provide improve filtration efficiency and better air tightness, but due to their configuration and characteristics, they do so in a more expensive and less elegant way and offer lower breathability.
For PRECIMASK®, here are the filtration efficiency results obtained according to EN 14683 AC for 5 samples of our filter cartridges facing a bacteria aerosol of 3 µm. This test allows us to determine the bacterial filtration efficiency (BFE) of the cartridge:
- Cart. 1 (BFE 96,53%)
- Cart. 2 (BFE 98.21%)
- Cart. 3 (BFE 96.37%)
- Cart. 4 (BFE 96.97%)
Based on the results of the bacterial filtration efficiency (BFE) characterization report from the Engineering and Health Center of the “Ecole Nationale Supérieure des Mines de Saint-Etienne”.
The results are clear :
Comparison of filtration levels
taking into account the leakage rate and filtration efficiency
- Leak rate : 8% (standardized)
- Filtration : 100% (particles of 3µm)
(100% – 8%) x 100% = 92%
Or 92% filtration
- Leak rate : 20% (not standardized)
- Filtration : 95% (particles of 3µm)
(100% – 20%) x 95% = 76%
Or 76% filtration
For the same filtration area, the ceramic filter cartridge of PRECIMASK® allows better breathability compared to most UNS, surgical, FFP and FMP masks.
We can estimate that a person at rest takes 20 breaths per minute of 0.5 L of air and therefore needs 10 liters of air per minute. However, an athlete can increase their oxygen requirements up to ten times and hence the respiration flow rate.
- Needs of a person at rest
- UNS1 mask
- Surgical mask
- UNS1 Sport mask
The breathability of a mask depends on the filtration medium permeability and the filter surface. In the table below, we report the inherent permeabilities of different filtration media and the permeability at a filtration area equivalent to two PRECIMASK® cartridges (Ø 36mm). The filtration area is greater for UNS1 and surgical masks to compensate for their lower permeability. The leakages around these masks also improve their breathability, but reduce the protection level as explained above. For PRECIMASK, despite the lower filtration area, a good breathability is ensured thanks to the excellent permeability of the ceramic filter medium.
Air permeability of the filter material at 100 Pa
Permeability related to the surface of the 2 PreciMask® cartridges
|UNS1 mask||> 96 l/m²/s||14 L/min|
|Surgical mask||> 139 l/m²/s||20 L/min|
|UNS1 Sport mask||> 300 l/m²/s||43 L/min|
|PRECIMASK®||> 380 l/m²/s||54 L/min|
PRECIMASK® are very innovative face masks which fill a normative void. they offer the same level of air tightness and reusability as FMP masks with a filtration medium having a retention efficiency equivalent to that of surgical masks. However, filtration cartridges of FMP masks have to be replaced on a regular basis, whereas in the case of PRECIMASK® there is no need to change filter cartridges.
The PRECIMASK® cartridges are more effective at filtration than the cloth / fabrics of UNS1 masks and at the same level of surgical masks. Furthermore, PRECIMASK® provides enhanced air tightness and hence higher protection. However, for the time being it cannot be certified as an UNS mask because of its design and long service life. In addition, the UNS mask requirements advise against cleaning protocols by heating or boiling textile face masks, as this may damage them. This is not the case for the stable materials with which PRECIMASK is constructed. The PRECIMASK structure can be easily cleaned with water and the cartridges can be placed in the oven or in boiling water.
Currently, there is no standard to exactly matches PRECIMASK® features. Confident in our concept and to allow everyone to protect themselves while preserving the environment, we offer our customers the possibility of purchasing and using PRECIMASK, whose filtration tests carried out by an independent laboratory have demonstrated its filtration efficiency.
The silicone seal in contact with the face has been designed and developed to ensure the user’s comfort, and also its protection, thanks to a material with the medical approvals necessary for direct contact with the skin.
At a time when ecology plays an increasingly important role in our lifestyles, we want to reduce the environmental impact of the COVID-19 pandemic through our products. Indeed, disposable masks are produced from synthetic fibers (polypropylene) which have long degradation times. Once worn, they will increase household waste or at best will be recycled (in insulation materials for example), when they are not directly thrown into our environment. The ability of PRECIMASK® to protect its wearer and the environment without generating waste or consumables, reduces the amount of waste generated by the COVID-19 pandemic by replacing several hundred disposable masks with a single reusable product.
Every month, humanity uses 129 billion surgical masks to protect ourselves from the pandemic. This represents 451,000 tons of waste.
Thanks to its ceramic filters, PRECIMASK® are the world’s first zero waste masks.
The shelf life of PRECIMASK® in its original packaging is more than 40 years (with specific storage conditions). Disposable masks have a shelf life of approximately 5-7 years. With PRECIMASK®, there are no need to renew stocks of disposabvle masks.
Last but not least, PRECIMASK® are designed, manufactured, and assembled in France according to the most stringent European quality standards. The ceramic filters, developed in the Saint-Gobain Research and Development center of Cavaillon (Vaucluse) is produced in France and Germany.
PRECIMASK® are masks with a very high level of protection and optimal durability. their enhanced air tightness provides protection for the wearer but also for their environment. Its filtration capacities allow them to protect the wearer against viruses carried by ambient aerosols. the ease of cleaning and durability allow them to be reused and generate no waste.