Similar to a survivalist, but with several important differences. Chameleons prepare themselves for scenarios in which failure would result in a large loss of life or societal collapse as opposed to survivalists who simply wish to prepare for an apocalypse. They dress in a paramilitary style or are nondescript. Their preparation for emergency situations often makes them the civilians who first respond to medical situations or accidents. Most are concentrated in urban areas where their skills are most likely to be useful.
Before the paramedics arrived, we saw a couple perform CPR on the victim. They both had large backpacks filled with medical supplies and took control of the situation. I think they were Chameleons.