Oxygen masks fall into three main categories. The main difference between the mask based largely on hermetic sealing of the mask to the face, the method of oxygen delivery and durability of materials and design.
Pilot mask designed to increase oxygen supply to the mouth and nose when in the unpressurised cabin at altitude, like in fighter aircraft. There is often a secondary regulator in the mask, to ensure safe and proper amount of oxygen to reach the pilot. You can check out https://nestforia.com/ for getting more knowledge about various face mask to fight with corona virus.
Medical oxygen masks are usually very light, small and usually wear. In many hospitals today, nasal tube is often used as a substitute for the delivery of oxygen mask, as the patient is much more comfortable, more in control and able in most cases to speak.
If you have heard of disposable respirators, they are no different from the N95 masks. They will be able to filter and block out dirt, coal, iron ore, flour and dust. You can be assured that other materials of similar type will also be able to blocked out. You can also be assured that sicknesses like the flu and tuberculosis can be avoided when you use these disposable respirators properly. You will have the added benefit, with a disposable respirator, in that you have a built-in respirator that comes with it. It is more than just a basic masks, you will be ensured that you still have a good amount of oxygen.