[blu]

respirators are for the medical people and ventilators are for the patients, correct?

NOPE. Think of it this way:

The ventilators do the breathing for the body. They perform the mechanical act of breathing, along with cleaning the incoming air.

Repsirators are to treat the air...to clean it, make sure the lungs get clean air.

[MagnoliaB]

So you use the two together at the same time? The respirators are attached to the ventilators?

[spokeshave]

Respirators are to treat the air...to clean it, make sure the lungs get clean air.

The problem with respirators and 3M 95 masks and similar is that they filter the air INTO the lungs of the wearer

however, there is a one way check valve on the air exit

so if the wearer has is infected with coronavirus

such as minor symptoms

the exhaled air from the wearer will contain a plume of coronavirus particles.