As to the question of rules regarding when and where peaceful protests may be held, that's highly dependent on the specific location of the protest.
The venturi mask, also known as an air-entrainment mask (and sometimes by the brand name VentimaskÂ®), is a medical device to deliver a known oxygen concentration to patients on controlled oxygen therapy.
Bag valve mask 1 Bag valve mask A disposable BVM Resuscitator A bag valve mask (also known as a BVM or Ambu bag) is a hand-held device used toprovide positive pressure ventilation to apatient who is not breathing or who isbreathing inadequately.ag valve mask 2. Method of operation The BVM directs the gas inside it via a one-way valve when compressed by a rescuer; the gas is then deliveredthrough a mask and into the patient's trachea, bronchus and into the lungs.