Automatic crash detection features on Apple iPhones and Apple watches have resulted in 18 false alarms to the St. John’s Regional Fire Department in the last five months.

The manager of technology and communications with the St. John’s Regional Fire Department, Jason Mercer, says the phone feature detects a quick stop or quick movement, prompting an emergency call to 911. The feature also allows the owner to cancel the call within 30 to 60 seconds, but even that fail-safe doesn’t account for human error.

Mercer says the feature is very helpful for someone who is involved in a crash and is unable to call 911 themselves, but the St. John’s Regional Fire Department is seeing a rising number of false calls from the Apple alerts.

It comes down to a common practice, which is to lay the phone on the roof of your vehicle while climbing aboard. As a result, firefighters are getting an increased number of calls from phones that have fallen off moving vehicles.

“We surmise that people may be accidently leaving their phones on the roof of their cars, and when they drive off, the phone hits the ground, and we get that call.” He says the fire department has to respond regardless, because they have no way of knowing which calls are actual emergencies and which are false alarms. “Since May, we’ve had 18 of theses calls that have been false. We have found phones sitting in the middle of the road, or on the side of the road, and later the owners have been able to pick them up.”