Recommendations for the use of respirators and face masks and recommended classes of protection for selected professions

The World Health Organisation (WHO) has issued several documents in which it informs in detail about the use of protective equipment and protective measures in relation to the COVID – 19 contagion and spread.  This recommendation summarises important facts.

The wearing of face masks is indicated by the WHO for persons with clinical signs of a respiratory disease, in order to prevent the spread of contagion in the environment.  Many countries recommend wearing them to all patients.  In the Czech Republic, the wearing of masks or any other protection of the respiratory passages is mandatory.
The use of respiratory passage protection is an important preventive measure that helps limit the spread of respiratory diseases, including COVID–19.  Still, mere use of respiratory protection, without any other measures, is inadequate.  It must always be combined with adequate hygiene and frequent handwashing. 
WHO, ECDC, RKI, and other recognised professional institutions recommend that healthcare professionals who are caring for and are in direct contact with infected patients, use the following protective equipment: protective coat, gloves, respiratory protection, and eye protection.

Healthcare professionals who are in contact with confirmed or suspected cases of COVID-19 infection should, according to the ECDC, wear (Ref. 1): an FFP2 respirator or a respirator with a higher level of protection, eye protection, long-sleeve protective garment (coat, overall), and gloves.

An FFP3 respirator is recommended for processes where aerosols are generated, e.g., tracheal intubation, tracheostomy, respiratory system aspiration, bronchoscopy, sputum induction, cardio-pulmonal resuscitation, etc.  A lower level of protection is adequate for all other processes (Ref. 1).

In the USA, the CDC (Ref. 2) recommends N95 respirators for healthcare professionals, the protective effects of which are similar to those of FFP2 (Ref. 3).

The evaluation as to whether an “ordinary” textile mask or a surgical mask should be used for covering one’s face, or, rather, a respirator, depends on an evaluation of the environment in which you operate and the activity in which you are engaged.  Excessive use of special protective equipment may result in a shortage thereof. 

When using a protective mask, abide by the following recommendations.  If you wear a mask, it is essential that you put it on and take it off correctly, and that you also dispose of it correctly.  Place your mask on carefully, making sure that it is covering both your mouth and nose, and tie it firmly such as to minimise the space between your face and the mask.  Do not touch the front of the mask while placing it on and removing it.  When taking your mask off, use the following process: do not touch the front of the mask, loosen the string or elastic at the back, and remove it. Once you have removed it, and whenever you have touched the front of your mask, wash your hands with soap and a disinfectant.  When your mask is damp, replace it with a new, clean, and dry mask.  Do not use disposable masks repeatedly.  Discard them immediately after use.

Due to the worldwide shortage of protective equipment, it is acceptable to use the same respirator in caring for multiple patients with the same diagnoses without removing the respirator, as long as it is not damaged, soiled, or contaminated.

Hospitals that are able to arrange sterilisation of medical devices or have their own central sterilisation unit may sterilise used respirators, for use by their medical staff, using tested sterilisation methods, in particular class FFP3 respirators, for their repeated use – up to three times.

If there is a risk of infecting patients, it is necessary to use respirators without an exhale valve or to cover the valve with a face mask.  In the event of a higher risk of the generation of aerosol, protective goggles or a shield must be worn.

Summary: In developed countries, including Europe and the US, an FFP2 respirator (or, in the US an N95 respirator, in China a KN95 respirator – both comparable to FFP2) is the recommended level of protection for healthcare professionals during their work, including for staff who are in contact with COVID-19 positive patients.  An exception are procedures in which contaminated aerosol is generated – an FFP3 should be used in those cases.

The recommendation will be modified as new knowledge arises.

Sources:

Ref. 1 https://www.ecdc.europa.eu/sites/default/files/documents/COVID-19-infection-prevention-and-control-healthcare-settings-march-2020.pdf

Ref. 2 https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html

Ref. 3 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5058571/

Advice on the use of masks in the community, during home care, and in health care settings, in the context of the novel coronavirus (2019-nCoV) outbreak, Interim guidance, 29 January 2020, WHO, online:
https://www.who.int/publications-detail/advice-on-the-use-of-masks-in-the-community-during-home-care-and-in-healthcare-settings-in-the-context-of-the-novel-coronavirus-(2019-ncov)-outbreak 

Rational use of personal protective equipment for the coronavirus disease 2019 (COVID-19), Interim guidance, 27 February 2020, WHO, online:
https://apps.who.int/iris/bitstream/handle/10665/331215/WHO-2019-nCov-IPCPPE_use-2020.1-eng.pdf

https://www.ecdc.europa.eu/sites/default/files/documents/COVID-19-infection-prevention-and-control-healthcare-settings-march-2020.pdf

Other sources:

https://www.who.int/docs/default-source/documents/advice-on-the-use-of-masks-2019-ncov.pdf

https://www.baua.de/DE/Themen/Arbeitsgestaltung-im-Betrieb/Biostoffe/FAQ/pdf/Empfehlungen-organisatorische-Massnahmen.pdf?__blob=publicationFile&v=4

https://www.rki.de/DE/Content/InfAZ/N/Neuartiges_Coronavirus/Ressourcen_schonen_Masken.pdf?__blob=publicationFile

https://www.rki.de/SharedDocs/FAQ/NCOV2019/FAQ_Liste.html#FAQId13528066

https://www.ecdc.europa.eu/sites/default/files/documents/COVID-19-guidance-wearing-and-removing-personal-protective-equipment-healthcare-settings-updated.pdf

Types of professions and the respirators and masks assigned

Profession Type of protective equipment
ICU healthcare professionals with ventilated patients FFP3 / GB19083
Staff at an infection clinic caring for COVID FFP3 / GB19083
Staff in risk zone 3 with potential occurrence of contaminated aerosol FFP3 / GB19083
Staff of a COVID-centre laboratory FFP3 / GB19083
Medical emergency service staff FFP3 / GB19083
Healthcare professional – sampling points FFP2 / N95 / KN95 / GB19083+ shield
Healthcare professional – emergency admittance FFP2 / N95 / KN95 / GB19083
Dentist FFP2 / N95 / KN95 / GB19083 + shield
Healthcare professional – regular department FFP2 / N95 / KN95
General practitioner FFP2 / N95 / KN95
In-patient specialist FFP2 / N95 / KN95
Pharmacist FFP2 / N95 / KN95
Food industry – clean premises FFP2 / N95 / KN95
Drivers FFP2 / N95 / KN95
Cashiers FFP2 / N95 / KN95
Staff in frequent contact with the public FFP2 / N95 / KN95
Army – frequent contact with the public FFP2 / N95 / KN95
Police – frequent contact with the public FFP2 / N95 / KN95
Firemen – frequent contact with the public FFP2 / N95 / KN95
Army – others Mask / FFP1
Police – others Mask / FFP1
Firemen – others Mask / FFP1
Energy sector Mask / FFP1
Other activities, administrative work, industry, forestry, agricultural work, food industry, general population  Mask / FFP1

Simplified table of respirator protection classes

Protection class / standard FFP2 N95, GB19083 (Level 1) KN95 (GB2626) GB19083 (Level 2, 3) FFP3
Filtering effectiveness ≥ 94 % ≥ 95 % ≥ 95 % ≥ 99 % ≥ 99 %