When Mauritians were expecting an early lifting of restrictions, the Prime Minister announced on Labour Day that the Curfew Order has been extended up to 1st June 2020. To further reduce the spread of the novel coronavirus among the community, he also confirmed the usage of face masks will become compulsory in public places and transport when lockdown will be removed in a phased manner. While the public sector through various ministries are currently working on Return to Work Protocols after confinement, the Prime Minister strongly advised that private enterprises to strictly followed the Best Practices on Post-Lockdown recently published by Business Mauritius. Here again, companies will make the wearing of masks compulsory at the workplace.
But there are so many different types of face masks on the market, and not all of them are really effective against the novel coronavirus. So, which masks do we have to wear to protect us against Covid-19?
To a safety & health professional, a good respiratory protective equipment won’t protect you unless it has the right filter and fits you well. You must also be adequately trained in how to use and dispose of it properly! Single use or disposable masks are different from re-usable respirators. The latter should be adequately cleaned, maintained and properly stored in an appropriate accommodation when it is not being used. But, for the layman (citoyen lamda), any homemade mask is better than nothing to protect oneself from Covid-19!

However, before choosing the right face mask for you, let us consider the main types and relevant standards of such respiratory protective equipment (RPE) available on the market.

I. Filtering Face Piece (FFP)

An FFP respirator is designed to protect the wearer from exposure to airborne contaminants and is classified under personal protective equipment (PPE). FFPs are mostly used by healthcare workers specially during aerosol-generating procedures

Filtering Face Piece
Filtering Face Piece

(e.g, dental treatment) in hospitals or dental clinics.
Filtering respirators can sometimes be equipped with an exhalation valve to improve user comfort. The valve prevents condensation inside the mask, misting on the glasses and helps the user breathe in and out easily.

Suffice to point out that FFP respirators fitted with exhalating valve are not appropriate for use as a means of infection control as they do not prevent the release of respiratory particles from the wearer into the environment.
In the United States, disposable FFP or reusable respirators must meet NIOSH standards. Within this standard, there are several classes of respirators depending on the degree of oil resistance:
• Class N: no oil resistance. A distinction is made between N95, N99 and N100. The number after the letter indicates the percentage of filtration of suspended particles.
• Class R: mask resistant to oil for up to eight hours. Here again, a distinction is made between R95, R99 and R100.
• Class P: a completely oil-resistant mask. There are also P95, P99 and P100.

Thus, it is necessary for American healthcare personnel to wear a respirator of class N, R or P. According to the Centers for Disease Control and Prevention, the N95 respirator filters 95% of airborne particles, and can even filter out bacteria and viruses.

 

In Europe, they must meet the European Standard EN 149:2001 which has three classes of disposable particulate respirators (FFP1, FFP2 and FFP3).
• FFP1 refers to the least filtering of the three masks with an aerosol filtration of at least 80% and leakage to the inside of maximum 22%. This mask is mainly used as a dust mask (during renovations and various types of work).

  • FFP2 masks have a minimum of 94% filtration percentage and maximum                   8% leakage to the inside. They are mainly used in construction, agriculture, and by healthcare professionals against influenza viruses. They are currently used for
    protection against the novel coronavirus.
  •  FFP3 masks are the most filtering mask of the FFPs. With a minimum filtration percentage of 99% and maximum 2% leakage to the inside, they protect against very fine particles such as asbestos fibres.

For European caregivers, it is necessary to wear a respirator of at least class FFP2 or FFP3 for maximum filtration of particles and aerosols when caring for a suspected or confirmed Covid-19 patient. The World Health Organisation (WHO) still recommends the general public to avoid using N95 or FFP2 respirators to ensure that frontliners or first responders have adequate supply of same to wear so that they can safely treat Covid-19 patients in hospitals and clinics.

II. Medical Mask (also known as surgical or procedure mask)
This mask creates a barrier between health personnel and patients by covering the mouth, nose and chin. Its external side which is hydrophobic (fluid repellent) prevents large respiratory droplets and splashes from reaching the mouth and nose of the wearer.
The inside layer of the procedure mask, being hydrophilic (moisture absorption) helps to reduce or control the spread of such droplets from the person wearing it. There is a middle layer acting as a germ filter.

A surgical mask is a disposable medical device that can be bought in pharmacies and that protects against infectious agents transmitted by “air droplets.”
These can be droplets of saliva or secretions from the upper respiratory tract when the wearer exhales. It can also protect the wearer from the risk of splashes of biological fluids. In this case, it should also be equipped with a visor to protect the eyes.
If worn by the caregiver, the surgical mask protects the patient and his or her environment (air, surfaces, equipment, surgical site). If worn by a contagious patient, it prevents the patient from contaminating his or her surroundings and environment. These masks should not be worn for more than 3 to 8 hours, depending on use. However, you need to change them once they become damaged, soiled with secretions and body fluids, or wet or damp or uncomfortable (difficult to breathe through).Surgical masks are tested in the direction of exhalation (from inside to outside). The tests take into account the efficiency of bacterial filtration. They do not require a fit test to ensure a proper seal with the wearer’s face.
In Europe, they must comply with the European Standard EN 14683:2019, which has 3 levels of bacterial filtration efficiency (BFE1, BFE2, Type R). In the United States, they must respect ASTM Standards which have three levels of protection (from low risk of exposure to fluids to high risk of exposure to fluids).

III. Barrier or Community Masks
The shortage of FFP2 respirators and surgical masks has fueled an increase in patterns and tutorials for making protective masks. A new type of protective masks has recently appeared and has been approved by certification organization, AFNOR. These include various types of self-made and commercial masks and face covers made of cloth, other textile fabrics or other materials such as paper.
AFNOR SPEC S76-001 – Barrier Masks: Guide to Minimum Requirements, Methods of Testing, Making & Use is the reference document with the requirements to be satisfied when making these new barrier masks. Textile companies can use this document to mass-produce these community masks.

The requirements for barrier masks are less ambitious than those for FFP2 and surgical masks, which should be reserved for healthcare professionals and other first responders. Barrier masks meet a set of criteria and they are aimed to reduce potential asymptomatic transmission of COVID-19 from the mask wearer to others. In the other hand, they provide healthy people with further protection, in addition to good hygiene practices and social distancing.
The use of such barrier masks in the community may be considered when visiting busy, crowded spaces such supermarkets, shopping malls, or when using public transport. According to RT Knits, the quality of face masks manufactured locally by its factory far exceeds the requirements imposed under AFNOR SPEC S76-001. However, these are not intended for use in hospital or clinic settings or by healthcare practitioners.

IV. Reusable Elastomeric Respirators

A respirator refers to a type of Personal Protective Equipment (PPE) which is designed to protect the wearer from exposure to a variety of airborne hazards. These include chemical contaminants in the form of dusts, mists, gases or fumes (e.g, welding fume). They also include biological materials. Thus, such a respirator protects the wearer from airborne infectious agents, i.e. against contamination by viruses such as Coronavirus, SARS, H1N1, etc.
Respirators are also used where work is carried out in areas where oxygen levels are low, for example self-contained breathing apparatus (SCBA) for entry into confined spaces. Here, we should refer to the definition of PPE under local legislation.

Unavailable in pharmacy, these tight-fitting half-face respirators are made of synthetic or rubber material permitting them to be repeatedly cleaned, disinfected and reused. Equipped with exchangeable filters which may have disposable components such as P100 pre-filters, etc. These are mostly used in the work environment where substances hazardous to health may be present. By the way, this type of respiratory protective device are used by workers handling asbestos containing materials (l’amiante) which are notoriously known cancer-causing substances.

Because a respirator needs a full-face seal, it’s going to be uncomfortable to wear for an extended period of time. The pressure on your face, the edges of the mask digging into skin, and even the adjustable fit of the mask are all going to be concerns.
Reusable respirators should be cleaned and decontaminated according to the manufacturer’s instructions.

General Discussions
The most common half-faced masks actually being worn by the general public are the unique use surgical (medical or procedure) ones. The key element that makes them masks rather than respirators is that they don’t have an air-tight seal against the face.
As some of you are aware, the right respiratory protective equipment which may protect us from the novel Coronavirus is referred to as N95 (NIOSH-Approved) or FFP2 (Filtering Face Piece Class 2) respirators designed to prevent 95 per cent of small particles from entering the nose and mouth area.

However, the Health & Safety Executive in England believed that fluid-resistant surgical masks provide sufficient barrier protection against COVID-19 respiratory droplets reaching the mucosa of the mouth and nose and may be used if FFP2 respirators are not available. You may also note that though medical masks are approved by Food and Drug Administration (FDA), they are not considered as respiratory protective equipment (RPE) by Centers for Diseases Control and Prevention (CDC) in the United States.
Now, what is the difference between the barrier (community) mask and a respirator? Those who studied Biology at college may recall about the teacher saying bacteria and viruses are termed microorganisms. This means that we need a special equipment called the microscope to be able to see them. That’s why our Prime Minister stated that we are at war with an invisible enemy! So, N95 or FFP2 respirators can effectively trapped these dangerous microbes or toxic dusts, thus preventing us from getting infected by Covid-19.
Suitable alternatives to N95 are KN95 or KP94 respirators, but designed to meet China or Korea Standards and has ear loops which create looser seal around the face instead of tight-fitting headbands. For frontline healthcare workers, wearing a properly fitted mask could be lifesaving. When using an approved respirator for the first time, a fit test is recommended by the manufacturer to ensure a proper seal to the wearer’s face.

For any style, hair should not cross or interfere with the respirator sealing surface. Clean shaven (no thick moustache and sideburns) is also important because facial hair hinders a good seal to the face.
Mass masking in the community is important in the fight against Covid-19, but that is not always about protecting oneself. It is more about protecting others from getting infected. So, if everyone is wearing a face mask, we are all protected! (Please the Urine Test at Appendix)

Since the World Health Organisation (WHO) has declared SARS-CoV-2 as a pandemic, it has always stated that the only two groups of people who should wear protective masks are those showing symptoms of Covid-19, who would need surgical-type face masks to reduce the risk to others, and those caring for people who are suspected to have the novel coronavirus who would need Respiratory Protective Equipment (RPE) to protect themselves.

On the other hand, healthcare providers or first responders, the use of approved PPE is highly recommended. WHO has therefore set Guidelines on PPE for Healthcare Personnel – A long sleeved disposable fluid repellent gown (covering the arms and body), an FFP2 respirator, a full-face shield or visor and gloves are recommended when attending to suspected and confirmed cases, regardless of the clinical setting.
Studies done in Guangzhou where people dining in neighbouring tables in an airconditioned restaurant without windows became infected with Covid-19 by an asymptomatic person returning from Wuhan (China’s epicentre) who was sitting at another table. It was concluded that airborne transmission could only be attributed to direct airflow from an air conditioner.

Recent research works conducted in South Korea also revealed that bioaerosols formed during speaking, coughing or sneezing could travel in air for quite long distances. The Japanese also could not explain how the contagion spread in cruise ship Diamond Princess where more than 700 passengers became infected even though they were confined to their respective cabins while the ship was quarantined ashore in Tokyo.
The above epidemiological studies have not, so far been conclusively enough to the scientific world. Just imagine that this aerosol theory happens to be true! Are we wearing the right protective masks?

Donning and Doffing of Face Masks by the Public
Proper use of face mask is critical to its effectiveness and safety. The general public is therefore advised to follow the steps mentioned below:
a) Clean hands with soap and water (20 seconds) or an alcohol-based hand sanitizer prior to putting the face mask on or taking it off.
b) Ensure that the mask fully covers the face from the nose bridge down to the chin. Those wearing glasses should make that metal strip is properly pressed
against the nose bridge to prevent fogging of lenses.
c) Avoid touching both surfaces of the mask once done.
d) When taking the face mask off, remove it from behind using the ear loops – be sure not to touch the front of it.
e) Reusable fabric (cloth) masks should be put in washing machine or washed as soon as possible after use with common
detergent at 60o C.
f) If face mask is disposable, it should be thrown in a covered bin for proper disposal.
g) Massive campaigns through TV, posters and videos to show the public the techniques on how to wear face masks will definitively improve its effectiveness.

I wish to highlight the laudable initiatives of some Export Manufacturing Enterprises and local companies including garment manufacturers which have also joined the fight with the Government in slowing down the transmission of Covid-19 in making non-medical masks for the community and face shields and gowns for our frontliners. We should be proud of those employees involved in the conception and design of these reusable and washable barrier masks which will be more accessible to the population at lower and fixed prices.

Moreover, some of these textile masks will be available in different sizes providing better fit to the respective users including children. But suffice to mention that donning any face masks is better than nothing!

Important Legal Aspects to Consider
Section 82 to the Occupational Safety & Health Act 2005 makes provisions for an employer to issue of suitable and appropriate personal protective equipment and clothing to protect employees against risks of bodily injury. The law also imposes on the employer to replace and maintain these protective devices; and where so justified, to cause any such equipment to be thoroughly cleaned, washed and decontaminated before being put into use again.

Amongst the legal requirements prescribed under the subsequent Personal Protective Equipment Regulations 2012 is that the standards of PPE should be acceptable to the Mauritius Standards Bureau. Last but by no means least, all reasonable steps must be taken to ensure that any PPE is properly used.

Section 85 to the same Act further stipulates that an employer has to notify the authority of any occupational accidents and dangerous occurrences (as per 11th Schedule) at the workplace.
Furthermore, the Training and Employment of Disabled Persons Act stipulates that employers should recruit among their workforce 3% of persons with some disabilities. The wearing of face masks at work could make it difficult for deaf or hearing-impaired employees used to lip reading to understand clearly work instructions.

In view of the above, present safety and health and other related legislations will most likely be amended accordingly through the Covid-19 Bill 2020 soon to be proposed at the Legislative Assembly. Will Government make the wearing of face masks mandatory as a sine qua none post-lockdown measure?

To conclude, the use of a face mask alone is insufficient to provide adequate protection against Covid-19 as considerations should be first given to engineering controls such as barriers, sneeze screens at reception desks and counters, dividers in call centres and at check-outs in supermarkets or decontamination tunnels before administrative measures such as washing hands, keeping social distances, working from home and others are adopted.
Stay home, stay safe!

Harold LEE, CMIOSH (UK
Chartered Safety & Health Practitioner
Vice-Chairman

Institute of Safety, Health &
Environment Management
Mauritius
Email: [email protected]

Affiliated to APOSHO (Asia-Pacific Occupational Safety & Health Organisations)

References:
1. Training and Employment of Disabled Persons Act, 1996
2. Occupational Safety & Health Act 2005, Act No.28 of 2005
3. OSH (Personal Protective Equipment) Regulations 2012, GN No. 146 of 2012
4. AFNOR SPEC S76-001 – Barrier Masks: Guide to Minimum Requirements, Methods of Testing, Making & Use
5. http:http://youtu.be/90x3JellkYQ Post C ovid 19 Dr Harry Phoolchund
6. https://facemask.mu/
7. https://www.iosh.co.uk/
8. https://www.hse.gov.uk
9. https://www.cdc.gov/
10. https://besafemoris.mu/
11. https://english.kosha.or.kr/english/index.do
12. http://www.oshc.org.hk
13. https://www.ilo.org/global/topics/safety-and-health-at-work
14. https://www.who.int/emergencies/diseases/novel-coronavirus-2019
Appendix: The Urine Test

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