I see that this disscusion is an undying one. Here are my suggestion at the topic.
-I see no problem with integrating a Ballisic Mask onto Gas Mask [it is not a typo]. As it would be simply a reinforced/armored variant of a combat gas mask.
-Also I see no problem with integrating a respirator into a Ballistic Mask as respirator itself is just set of filters. That keeps miniaturizing with time. At the beggining of bio/chem warfare at some point WWI they were big as 1.5L bottle so it was attached to chest, or backpack, with a hose to the mask itself. Nowdays commercial and military ones are quite small, the active carbon filtering system for most of biohazards is a size of big coin up to a size of can of sardines.
-Oh, so I wouldn't mind integrating respirato to a gas mask as it is a spall system, and doesn't need to be
inside gas mask itself, it could a back up. With another 'hose' for it. As you still need to activate the gas mask, so why not put the respirator on the 'exterior vent' of the gas mask?
-One of the last things that come to my mind, the respirator is not devined quite well. Does it or does it not cover your eyes? This is crucial for countermeasuring some hazards, like peper gas.
It makes me think of something closer to Cobra Commander.

-In my judgment this is a respirator, as it have a filter, not air supply of its own. As for me those simple medical mask and industrail mask so commonly seen on japanese streets also are some kind of respirators. So those wich Xenon posted would be more accurate.