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 mask device. A manually operated resuscitator used to ventilate a nonbreathing patient or assist the ventilation of a patient who is not breathing at an effective rate or tidal volume. The device consists of a bag, an oxygen reservoir system, a one-way flow valve, and a clear face mask.