Yes. But it has to be hospital grade air and the bottles can only be used for breathing air. A test report should always be provided and kept, and filed. Always purchase your breathing air from a reputable source.

My last comment I accidentally deleted, this is a pressure demand SAR with escape but needs an air source.

this
https://sps.honeywell.com/us/en/products/safety/respiratory-protection/supplied-air-respirators-sar/pressure-demand-sar-with-escape-cylinder-niosh

Plugs into this
https://sps.honeywell.com/us/en/products/safety/respiratory-protection/supplied-air-systems/honeywell-ac4000-air-cart

I think you are referring to an air cart as long as you are talking pressure demand. You can also use a cascade system with larger tanks that can still be portable. Just depends on how much air you need.

https://sps.honeywell.com/us/en/products/safety/respiratory-protection/supplied-air-systems/honeywell-ac4000-air-cart

Maybe you’re referring to more of an escape respirator like these if you’re not talking about SCBA.

https://sps.honeywell.com/us/en/products/safety/respiratory-protection/escape-respirators

I've always referred to this as an SCBA with a pigtail. Adapters are sold for most makes that fit either on the 1st stage or somewhere before the 2nd stage regulator.

https://www.grainger.com/product/45YR76?ef_id=CjwKCAjw3_KIBhA2EiwAaAAlilef4-ufhAe3BcNvrLSrt5I-UvDjcz4q5-62sizDF4MgyGm6LGyb0hoC-dAQAvD_BwE:G:s&s_kwcid=AL!2966!3!496359974110!!!g!470577457359!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=CjwKCAjw3_KIBhA2EiwAaAAlilef4-ufhAe3BcNvrLSrt5I-UvDjcz4q5-62sizDF4MgyGm6LGyb0hoC-dAQAvD_BwE&gclsrc=aw.ds

Not sure what you are describing. SCBAs are equipped this way.
https://www.3m.com/3M/en_US/p/d/b5005047169/