There was always an awkward moment for Timmy Reen after the fire was out. Standing amid the smoke and steam and wet debris, the other firefighters would shut off their oxygen tanks and pull off their face masks. But not Firefighter Reen.

The other guys ribbed him as they poked at ash and drywall, searching for embers. “Shut your bottle, Reen,” they’d say, nodding to his tank.

In the macho culture of the Fire Department of New York, showing too much concern over lingering smoke was a sure way to stand out. There’s a reason firefighters call themselves smoke eaters.

“Mind your own business,” he’d say. But sometimes the teasing would get to him and he’d pull his mask off. Even then, he’d hold his breath for 20 or 30 seconds before sneaking a sip of air from the mask dangling at his waist.

The funny thing was that this is what he got grief for — trying to avoid wafting carcinogens. Of all his idiosyncrasies, and there were lots, this was among the most rational.

A small sampling of the others: He brought his own sheets and pillowcase for overnights at the firehouse. He wiped down everything with his own stash of bleach wipes — including the inside of the fire engine. In his back pocket, he had a second remote control for the fire station’s TV, so he wouldn’t need to touch the shared one.