Check their film [if available] for other personal protection items worn, besides the gas masks. Filling chemical munitions [unless binary agents - which would be too advanced for the excremists] is a nasty business and would require a full protection suit and heavy gloves. If they were wearing their masks with T-shirts, then it is 200% BS propaganda flick.
True....but it certainly shows 'intent' and should be worth a MOAB or two..(grin)