Masks: qualification versus use 

For the purpose of preventing the spread of the new Coronavirus (SARS-CoV-2), it has been advocated the use by health professionals of masks regulated as medical devices (surgical masks type II and IIR) and as personal protective equipment [( semi- masks) respiratory protection (FFP2 and FFP3) self- filtering ]. 

Masks for clinical use, generally referred to as surgical masks, are medical devices that are intended to cover the mouth and nose of the health professional, functioning as a barrier designed to minimize the direct transmission of infectious agents between the professional and the patient. In this case, the main purpose of the product is to protect the health and safety of the patient, regardless of simultaneously also protecting the professional. 


 

The standard EN 14683: 2019, harmonized under the Medical Devices Directive, is intended for masks for clinical use, classifying them into different types (I, II and IIR) according to their characteristics, namely: the efficiency of bacterial filtration, differential pressure (mask permeability to air), splash resistance and microbial cleaning ( bioburden ).

 

The following table, extracted from the mentioned standard, summarizes the performance characteristics according to the type of masks: 


Table 1 - Performance characteristics by type of mask for medical purposes  

 

Masks that are intended to be worn by users with a view to protecting themselves against one or more risks likely to threaten their health or safety are classified as personal protective equipment. 

The standard EN 149: 2001 + A1: 2009 applicable to filtering respiratory protection devices (APR), namely the so-called “respirators” or “self - filtering semi-masks ”, classifies this equipment in FFP1, FFP2 and FFP3, taking into account their efficiency of filtration and its maximum inland leakage (FFP3> FFP2> FFP1):     

 

Class

Efficiency

Total escape to the interior

(laboratory tested)

Penetration into the filter material

(maximum%)

Examples

FFP1

Low

22%

20%

Some metallic particles. Plaster dust. Concrete dust. Work context.

FFP2

Average 

8%

6%

Woodwork. Earthworks. Paint spray gun with aqueous based ink. Molds and fungi. Viruses and bacteria .

FFP3

High

two%

1%

Typical in work with dangerous products, as in the chemical, pharmaceutical and paper industries. Viruses and bacteria. Sawmill. Replacement of filters.

 

Table 2 - Performance characteristics for class half masks Respiratory Protection AutoFiltrantes (in: "Protection Devices Selection Guide Respiratory Filter", the Portuguese Quality Institute dated 2016) 

 

Due to the rapid evolution of the COVID-19 pandemic, the use of masks is increasingly an issue of debate, as a complementary measure to limit the transmission of SARS-CoV-2 in the community. Within the general framework of the guidelines on the prevention of exposure risk, it is relevant to promote a wider use of masks by the community, as well as to define the criteria and requirements that they must meet in terms of design, performance and usability. 


 

The definition of these criteria, namely in terms of filtration, breathability, dimensioning and resistance, was the subject of consensus by a group of experts with technical skills in the medical-pharmaceutical, textile technology, infection and disinfection, standards and tests to be applied, inspection, etc. 

Simultaneously, there has been a mobilization of the national business fabric, to collaborate in the joint effort to fight the pandemic, reconverting the production lines for the manufacture of personal protective equipment and essential medical devices. These companies are available to put on the market masks in single-use fabric, or even reusable ones, which, failing to comply with the safety, health and performance requirements established in the laws applicable to medical devices and personal protective equipment, may conform. requirements to be defined for community use. 

The responsibility for the conformity of these masks with the requirements to be defined will rest with the manufacturer, who must choose appropriate raw materials, design, manufacture and label the masks so that they comply with the defined requirements, as well as test them according to the applicable normative references, in a laboratory recognized for this purpose. 


 

Categorization of masks by type of user: Thus, a system for categorizing masks used in the context of COVID-19 is adopted, considering their purpose:  

  • Level 1: masks intended for use by healthcare professionals. At Mipmed you will find the following level 1 masks: FFP2 , Type IIR 
  • Level 2 : masks intended for use by non-health professionals are exposed to contact with a large number of individuals. At Mipmed you will find the following level 2 masks: Anti-Covid , pediatric , Type I , Reusable community , Social disposables 
  • Level 3: masks designed to promote group protection (use by individuals in the context of their professional activity, use by individuals who contact other individuals with any type of mask and use in authorized exits in the context of confinement, namely in indoor spaces with multiple people). 

 

The use of these masks does not imply any changes:  

  • containment measures;  
  • hand hygiene and respiratory etiquette;  
  • the organization and procedures to be adopted, namely, by schools and employers that make it possible to improve the protection of employees. 


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Level 2 and level 3 masks classified as Textile Articles 

Level 2 and level 3 masks, not classified as medical devices or as personal protective equipment, and designated as textile articles, should be tested by the methods referred to in the previous table, taking into account that the results achieved with the biological model presented in standard of medical devices , to assess filtration performance, correspond to the results given by the measurement of inert particles, as proposed in the standard of personal protective equipment. 

Resistance to wear during the time of use should also be considered, since changes caused by wear can induce greater retention and bacterial growth. Regarding the reuse of these masks, performance studies should be carried out after simulating the actual use and the number of maximum reuse cycles foreseen. 

Information about the reuse process (washing, drying, conservation, maintenance) and the number of reuses must be provided by the manufacturer to the user. The user must also be informed of the performance characteristics and the product must not be a medical device or personal protective equipment, as well as the composition, must be made available through the labeling or marking of the textile product. 

Manufacturers must notify ASAE of the manufacturing activity and of the masks manufactured and keep a brief technical dossier of the product available to the authorities, including the characteristics of the raw material, the description of the manufacturing process, the information to be provided with the product. and the reports of the tests carried out and of the product's conformity issued by a recognized laboratory, namely accredited laboratories for the indicated methods. 

In this context, a group of experts with technical skills will operate in the medical-pharmaceutical , textile technology, infection and disinfection areas, and also include elements from DGS, INFARMED, ASAE and IPQ, as well as others who, according to their respective powers and competences , prove to be essential for this purpose.

 ASAE is responsible for inspecting products classified as textile articles, as a Market Surveillance Authority. 

 

Lisbon, April 14, 2020.

https://www.infarmed.pt/documents/15786/3584301/M%C3%A1smes+destinadas+%C3%A0+utilizes%C3%A7%C3%A3o+no+%C3%A2mbito+da+COVID-19/ a7b79801-f025-7062-8842-ca398f605d04

 

Catarina Vilela - Nurse