Everyone out on the field needs to have a mask on, no matter who it is or what they do. As far as what I carry on the field with me, I have my XSV pants(very nice), jersey, mask(duh), pod pack, 2 battle swabs, & marker set-up.
When we get together for a sorte in the Swamp. I wear all black with a standerd Mask, 4 reloads, assault marker with a 20 oz canister (and a 9 oz emergancy bottle), then i also carry a ten round side arm that uses the small 1 oz cillinder.
We go till we can't go no more