Most haunts do the toxic waste with florescent green paint and they black light the foam so it glows. I like to light those kinds of sets with claxon lights so there is not a constant light source. If you can add an LED inside the glass of the gas mask that you can trigger on and off. Make a few dummies that are dressed like you so you can blend in, then you can trigger the LED and lunge for the scare. Highlighter guts can make your water glow.