The short answer is that one may definitely wear a scarf in a way that covers both the nose and mouth. And, according to most rabbis, one may wear a protective mask outside on Shabbat as well.

The Longer Answer

While the permissibility of wearing a scarf in a manner that covers both the nose and mouth is pretty straightforward, wearing a mask outside on Shabbat is a bit more complicated.

On Shabbat, although we may not carry things outside of an eruv, we may wear garments or a tachshit (lit., jewelry). But what constitutes a garment?

Additionally, even if an item is deemed a garment, the rabbis prohibited one from going out with a garment that a person is prone to removing and carrying.

Different Types of Masks

Whether something fulfills the criteria of a garment depends, among other things, on the material it is made from, the purpose it serves, societal norms, and how it is worn.

Interestingly, the Talmud and Code of Jewish Law make mention of not going out with a mask on Shabbat.1 However, that is referring to a face mask worn as a costume (to scare children), which is clearly not the case here.

A face mask that is worn for protective purposes is seemingly no different than an item worn to protect one from pain or injury, which is considered a garment and may be worn outside on Shabbat.2 This would be permitted even if it is not worn exactly like an ordinary garment is usually worn.3 Given that, in colder climates, people do wear masks over their nose and mouth, it seems clear that a mask would fall into the category of ordinary garments.4

Wearing Anti-Semitic Jewish Badges

But even if masks aren’t garments that people ordinarily wear, does the fact that they are now commonly worn—since they are either mandated or strongly encouraged by the government (depending on your locale)—render them bona fide garments?

In the 12th century, Rabbi Yitzchak ben Moshe (author of the Ohr Zarua) wrote about the anti-Semitic badges the Jews of France were mandated to wear at the time. He ruled that one was permitted to go out with them on Shabbat since the badge was attached to the garment and therefore batel, “nullified,” to it.5 This seems to indicate that the fact that they were mandated alone is not enough to render them a garment.

However, the two scenarios are quite different. In the case of the badges, unless they are attached in some way, they aren’t being worn at all. Masks, on the other hand, are actually worn, and the only debate is whether wearing them would be considered the societal norm. Thus, the government mandate and the resulting mask-wearing by the masses should in itself suffice.6

Prone to be Removed

While we have outlined some of the reasons why a mask would be considered a bona fide garment, masks are at times very uncomfortable to wear, and people are prone to adjust them or remove them (partially) from their face to speak to someone. This brings us to the question of the rabbinic prohibition of going out with a garment that people are prone to take off.

We find, however, that this concern is not as great in a situation where there is a strong reason for the person to keep the garment on. Thus, for example, if one were to wear gloves outside in a warmer climate, there is a halachic concern that the person would remove the gloves in order to scratch himself. However, in a colder climate, this is less of a concern and the need is greater, so we may be lenient.7 The same would seemingly apply to wearing a mask outside, when its whole purpose is for protection.8

In light of the above, it would be permissible to wear a mask outdoors, although we pray for the day when all will be healed and these measures will no longer be needed.