Pub goers will be breathalysed at some of Whitby’s watering holes this weekend and refused entry if they are drunk.
The machines are being trialled in the town to try and prevent fighting and anti-social behaviour among revellers.
Door-staff will be asking people to blow into the device and results work on a traffic light system.
It will show green for no alcohol, amber for some alcohol in the system and red for anyone who is three times or more over the drink drive limit. They will then refuse entry to anyone who blows red.
The pubs trialling the scheme are Raw nightclub, Beez, The Pier Inn and Rosies (The George).
Police say it helps door-staff when they are refusing entry to someone who is too drunk because the machine says how much they have drunk rather than it being personal opinion.
In other areas it has helped reduce disorder and people are even asking to be breathalysed to see how drunk they are.
Whitby’s new police inspector, Andy Everitt said: “What is the level of drunk? Everybody is different. We have introduced alcoblows which are like the breathalysers we use on motorists.
“They are calibrated to three times the drink drive limit, which we think is a reasonable level of drunk.
“It allows door staff to refuse someone subjectively rather than objectively and helps those working in the late night economy and the last stops before the club in the Wellington Street area.
“It is also highlighting where people are coming into town later but have already consumed a significant quantity of alcohol.”