AGA Divator MK II Mask from Air Source One

Face mask Image	The face mask with inner mask is made of silicone and provided with a flat visor. The sides of the visor are mat finished to avoid optical distortions which may be very irritating. The mask has holed studs for fitting spectacles. In the connection piece for the breathing valve there is space for a microphone to a diving telephone. (When fitting a microphone a cover with long screws should be used). The head harness has five straps that are tightened and locked by stainless steel buckles. The wide and soft sealing edge of the mask is pressed lightly against the face by the positive pressure and follows the contours of the face giving an effective seal. Note: Always pull down the head harness as far as possible at the back of your head and tighten the lower straps first to counteract the buoyancy of the mask. A breathing apparatus must be physiologically correct in order not to tire the wearer and increase the air consumption. Rebreathing of carbon dioxide enriched exhaled air must be eliminated as far as possible (small dead space) and the breathing resistance must be as low as possible whilst the equipment must have sufficient capacity to cater for even an extremely hard work rate. The dead space has been minimized by the inner mask and separate inhalation and exhalation channels which coincide with channels in the breathing valve. In that way inhalation and exhalation air will never be mixed. During inhalation, air flows from the breathing valve up through the demister ports over the inside of the visor preventing any condensation from forming, and on through the non-return valves into the inner mask. During exhalation, the air is expelled to the ambient water through the exhalation valve.
Low Volume Diving Visor	DIVATOR MK II is fitted with a low volume diving visor. The visor is designed to minimize the volume of air inside the face mask and so reduce the positive buoyancy effect. If it is required to trim the mask to a neutral buoyancy, weights are available which can be attached to the locating lugs on each side of the visor. In addition the visor is closer to the wearer's eyes which gives the user an increased angle of vision. The low volume diving visor is suitable for use with any DIVATOR MK II masks and is available as a retro-fit kit or complete assembly.
Breathing Valve	The breathing valve is of the demand type ie. air is only supplied during an inhalation. The valve is designed to give a slight positive pressure of approximately 200 Pa (20 mm water column) in the mask. The positive pressure (safety pressure) is turned on automatically when the user takes his/her first breath in the mask. This ensures that there is no way of forgetting to turn on the positive pressure or that it could become accidentally turned off. The positive pressure reduces the risk of inleakage (which is very important when diving in contaminated water) and the positive pressure in the mask is maintained irrespective of the diver's momentary air consumption. But if water should still have penetrated, the mask is easily drained by pushing the purge button of the breathing valve. When the mask is taken off, the black lever on the breathing valve should be turned in against the housing. The breathing valve is then shut off. Owing to the balanced valve function, the breathing resistance can be kept extremely low, in spite of variations in the secondary pressure which may occur e.g. in connection with surface supply diving.

Interspiro (AGA masks, Buddy Phones, etc,)