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Officers are working to keep drug impaired drivers off the streets and now have a new tool at their disposal to help do so says police Chief Shelley Zimmerman.

The San Diego Police Department announces that they are deploying two "Drager 5000" testing devices which will screen saliva samples for 7 non- alcoholic substances, including cocaine, marijuana, amphetamines and prescription narcotics.

“It’s all about safety,” she told reporters at a midday briefing at Dana Point on Mission Bay.

The new devices will make their debut on the streets tonight during the annual St. Patrick's Day checkpoint that will be set up at a currently undisclosed location.

These new devices are expected to be put to regular use at checkpoint locations as well as DUI "saturation patrols" according to SDPD traffic-unit Officer Mark McCullough.

Motorists will get the choice of undergoing an oral swab and if the refuse that then they will be arrested on suspicion and will be given a blood test anyway.