A breathalyzer is n instrument that measures the alcohol content in a person’s blood stream. It is done so as to avoid accidents on the road due to drink driving. It is conducted as a “field sobriety test” by the officers and the test is called “preliminary breath test” or “preliminary alcohol screening”. It is a handheld unit which makes use of the electrochemical platinum fuel cell.
The Multiple Use Breathalyzer works on the same principle as the normal breathalyzer. It does not directly measure the alcohol content in the blood but it examines the alcohol content in the air that is exhaled. It only gives an approximate measure of alcohol present.