Whether it’s how you hang the two-tone surgical mouth and nose cover on your face, maybe someone curious.

Yes, because a lot of effort has been put into making the mask in front of the dressing direction.

A few test subjects have worn a similar mask on your face for days before you to make sure the inside of the mask does not cause facial skin irritation.

- The outer layer of the mask has the same basic material as the inner layer, but the filter cloth entering the inner layer has been tested for irritation, in which the user's skin is exposed to the mask cloth for ten days, says Kari Luukkonen, Business Director of Danish filter manufacturer Fibertex Nonwovens.

Masks are subjected to a so-called tissue compatibility assessment during their approval process.

It seeks to ensure that the fabric surface of the mask that comes into contact with the skin does not cause harm to the wearer, such as rash, due to cytotoxicity, irritation or sensitization.

The desired wearing direction of the surgical mask is indicated by the turquoise color of the outer layer of the mask.

It is a tradition.

That is, the blue side of the mask comes out and the white against the skin.

While outward surgical mouth and nose pads all look pretty similar, there are also differences between them.

Strictly speaking, surgical masks are divided into three categories according to their intended use.

Class I masks are intended for patients to reduce the risk of infection.

The bacterial material of the masks has a filtration efficiency of 95 percent or more.

Class II protection, on the other hand, is intended for use by operating theater staff.

The highest level is represented by the Type IIR version, which is intended to protect the user not only from airborne particles but also from splashes.

Such masks are used especially by surgeons.

Although both sides of the mask are similar moisture-resistant melt-spinning polypropylene fibers, the properties of the outer blue layer of the mask are still often sharpened with a drop-repellent coating.

It is in that coating that there is a risk of possible skin irritation, and therefore the direction in which the mask is worn matters.

In melt spinning, as the name implies, a solid polymer, or plastic, heated to a molten state is compressed into fibers that solidify in air.

from the mask to the interior of the fabric may be left in the manufacture of a slightly thicker outer side of the fabric.

It can be brushed with a lint-free surface for added comfort.