A breathalyer test is a machine that is used to measure a person's blood alcohol level.It is a tool that is employed by police officers to determine whether a person is legally able to drive in relation to their blood alcohol level. The degree to which a person's blood alcohol level can be and still be within legal guidelines differs in some states and countries. It works through a person blowing into a straw that is hooked to the device. A set amount of time is needed to be maintained in the breath that is being measured. There are two types of breathalyzer tests and the one that is used by police officers is less effective than the larger breathalyzer testing unit that the police stations will have, as do hospitals.
Justipedia explains Breathalyzer Test
If a person is pulled over while driving and asked to perform a breathalyer test, it is required to be taken. Ignoring the request will end up with the person being taken to the police station or sent to the hospital to determine their blood alcohol level via blood test. If a person attempts to give the sample and is unable to do so through use of the hand held breathalyzer test, they will be taken to the station to fulfill a better sample. The police have it in their ability in every country to force a driver to take a breathalyzer test where there is reasonable doubt that the driver may be under the influence of alcohol and/or drugs.