The best replacement for respirator is ventilator.

The best alternatives to respirator are rated as following:
★★★★★  ventilator
★★  dust mask
★★  gas mask
★  life support
★  mask
★  surgical mask
★  face mask
  trach
  n95
  ventilator difference
  household multi purpose respirator
  mechanical ventilator

Your alternative for respirator is not listed? Suggest!
Speaking about respirator, one probably shouldn't forget about face shield.

Other search terms related to respirator and their ratings are:
★★★★★ face shield
You have in mind a companion for respirator and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of respirator in all years. Click on graph for more.
respirator
ventilator
dust mask