The goggles look like standard Air Ministry RAF Mk.Vb Spectacles with the flip shield removed. The mask I cannot identify. The microphone on the mask looks like the same type used by the RCAF in Canada on the Type D oxygen mask. It is a somewhat bulky bakelite affair which resembles a small hockey puck! You can see it being used with the D masks in the other photo of the group of airmen from the same unit. The mask kind of resembles a Gutta Percha, maybe an early example. Interesting photo.