Particulate disposable masks

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The particulate mask called too N95 (or N99-N100), HEPA mask, in North American areas is THE mask which is able to protect from strains as SARS, flu, or tuberculosis. They should be prefered to surgical masks for daily gear or health care use if a pandemic occurs. Stewardesses, nurses, common people often wore them during SARS times, despite of how uncomfy or bulky they feeled.
They can be found at all providers for industrial needs, or even homecraft shops. The price is far higher than surgical masks.
The design of these masks prevents leakage by offering a tight face seal, and the thick filtering cup holds most of the tiny particulates. They can have an expiration valve, which helps to reduce the breathing resistance and the heat inside the mask. But a valved mask should never be used by a sick patient, and the valve in some models is not 100% safe ...

A lighter design, yet N95 norm, is the Pleats model, which can be worn folded or unfolded for a lower breathing resistance. It exists in size small (for teens and women), but the coating is less efficient than the best new particulate masks.

Traditional cup design has been improved since last ten years. Moldex as instance :

Other brands develop folding models, the expiration valve when present can be on the top face, or on a side face of the mask.

Brands as Dräger or MSA sell now those kinds of models against Avian Flu hazard.

3M offers a wide range of traditional cup masks, up to the high filtration bulky models. 8170 and 8210 models were a best used model during SARS and were been widely used against Tuberculosis.

3M has designed too a new serie of masks, folded and seealed in indivual package for more convenience. They are more comfortable than the traditional cup series.

Asian industry provides masks designed for the flat face profile.

Surgical masks

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Surgical masks are the first line of efficient disposable respiratory protection. Avoid the gauze style thick masks, always worn by Asian people. They only stop the saliva droplets, and become damp quickly. Even worn tight to the face, hair up, even if they better fit the flat facial type of the inhabitants.

Light paper procedure masks, as worn by the girl on the right of the second pic below, must be avoided, even to wear in public places. They leak, become damp quickly, and do not filter much.

Surgical masks have a color code, blue or green most times; they are fit with tie on straps, not earloops, the outside of the mask is coated against fluid projections, but these masks are not particulate masks. They are efficient to prevent someone from transmitting germs, and protect against damp droplets. The metal nose strip must be moulded to the nose, the straps must be tightly attached behind the head, but these masks are not air tight and can offer side leakage. A common view during Sars outbreak.
Since there was a shortage of particulate respirators, many healthcare workers in Asia doubled or even tripled their surgical masks, to offer a better protection against infection.

Why a protective personal equipment should be considered?

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Why a protective personal equipment should be considered?

Diseases as flu, SARS, are highly infectious in close contact situations, and the human transmission can spread quickly. The contamination occurs mainly by the transmission of infected particulates to human mucous membranes: mouth, nose, eyes, respiratory tracts, maybe ears... People would carry the virus on their hands. Therefore, by shaking hands, by door handles, whatever is touched by human contact could be contaminated, carry the virus and spread the disease.

The virus by itself is not found alone in the environment; for the contamination to be effective it is encapsulated in cells as saliva droplets or any bodily fluids. It can survive too on some surfaces for hours, even days maybe: WHO thinks the H5N1 avian influenza virus can survive for more than one month in bird droppings in cold weather and for nearly a week in hot summer temperatures. Infected birds or faeces can be contaminated too, and this dust should not be breathed in, neither touched.

This virus is destroyed by many disinfectant agents or UV, or heat.

Masks, goggles, gloves and gowning/suiting are the main protective items if we had to deal with such a strain..

During a pandemic wave, one can be exposed to infectious people, diagnosed (in healthcare context) or yet undiagnosed. With classic influenza, the infectious period begins about 24 hours before the symptomatic period, which allows infecting people before the person knows he is sick and thus more likely he will have contact with others. You see the point … Not speaking of healthy infectious careers. Current data for H5N1 infection indicate an incubation period ranging from 2 to 8 days and possibly as long as 17 days.

That why the bird flu is a main concern if it develops in a pandemic form, much more than the SARS virus. And why you should think to carefully protect if a deadly new form appears.

Another potential concern of the bird flu are the bloody sputum, blood-tinted respiratory secretion, watery diarrhoea, vomiting. All these hypothetic symptoms, already observed in some patients, could be an extra hazard and should ask for an appropriate protective gear, waterproof. Think to some Spanish flu like form mixed up with some Ebola, in the worst scenario.

Different levels of protection should be considered if :

- You are in a crowded place with uncontrolled population (as streets, public stores, any public halls)

- You are in a closed space for hours with uncontrolled population (as planes, offices)

- You care for a suspected or diagnosed patient (in healthcare context or at home)

- You have to disinfect or clean an area.

The protection runs from a good surgical mask for far contacts or for a sick person, to a particulate respirator, disposable or not, with perfect eye protection, and even a full suit for a high risk procedure, up to NBC norms.

The range of the protective equipment will depend too upon the infectiousness and death rate of the strain.

When you plan your equipment you have to consider the shortage of protective equipment which could occur if the pandemic is a severe one, and think to reusable items.

In any cases, you need to be trained how donning, wearing, putting off the gear in the right way, else it is useless and the protection you wear is a pure myth. Needless to say, following strict general hygiene rules is a must too.

Rather than an endless discussion about the filtering level required for your mask, you should first consider the proper fit of your gear and strict procedures of dealing with it. Which is the most difficult point to get used to.

When identified, SARS infection yet still occurred among healthcare staffs mainly because the isolation barrier was broken somewhere.

1918 : Spanish Flu

One of the most devastating pandemic in the History, with the Plague in Mediaeval Ages, is the flu known as "Spanish Flu", which made a final point to the WWI - millions of deaths worlwide, the amount is always unknown, but some cities as Philadelphia were hit by threatening waves.
The flu affected mainly young people. The lack of antibiotics and respiratory assistance explains the ratet of deaths. Its infectiousness looked highest, and the cloth/gauze masks were likely not an enough efficient protection against contamination. In public places of San Francisco and Philadelphia, as instances, masks were required. On pics and some short news movies, we can see how heavily covered were the nurses.

During SARS outbreak, masks were worn in public places

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Masks were higly recommanded or required for anyone who was in public places.

In a Conference Dr Sheela Basrur explained that they were a must during this outbreak.

People often added vynil or latex gloves to this gear.

People put masks in bus, train, subway, and plane.

Inside the campus, students had to wear masks, as well as employees in offices, food shops, sellers in their shops, and even children at schools.

In crowed places as streets, shop centers, masks too were recommanded. Even for wedding the bride was masked!

In hospitals, or at doctor's, masks were required fore everyone.