Why fire trucks carry a tiny brass plug on every hose fitting

That tiny brass cap on a fire truck's bumper hose port isn't a dust cover. It's a 200 PSI-rated plug built to a threading standard invented after the 1904 Baltimore Fire, and its chain tether became mandatory because of a 1987 Memphis warehouse fire that nearly killed a crew. Here's the full story. Subscribe to Object Theory for more. #firetrucks #firefightingequipment #nfpastandards #engineering #hosefittings Some links may be affiliate; we earn a commission at no extra cost to you.