Sometimes the help you can offer others in life is all about being in the right place at the right time, but it’s also extra handy if you happen be carrying a carbon monoxide detector. You know, just in case the Dunkin’ Donuts you’re in at 4 a.m. has dangerous levels of the stuff.

A Dunkin’ Donuts customer who just so happened to be an ambulance technician wearing a carbon monoxide detector walked into a New York restaurant in the wee hours of Friday, seeking a cup of morning coffee, reports the Associated Press.

When he entered the store, his detector went off, meaning there were high levels of the poisonous gas in the place. So he did what any good emergency responder would do and had all the employees leave the Dunkin’ and called the police.

Upon further investigation, officials found that a vent in one of the ovens was the source of the problem. Police told the New York Post that the carbon-monoxide level was at an elevated 35 parts per million.

As for whether or not the store had its own functioning, carbon monoxide detectors, instead of just relying on customers to bring their own, that’s unclear. But if you’re in a store and feel tired, nauseated, get a headache or want to vomit, those are all signs of carbon monoxide.

Dunkin’ Donuts patron sounds carbon monoxide alarm [Associated PRess]

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