Principle
There is a predictable relationship between blood alcohol concentration and breath alcohol concentration. Consequently, breathtesting is an accurate and reliable means of assessing alcohol intoxication. It has a well established basis within forensic science and law enforcement.
Because of the predictability of the blood/breath relationship, there is statutory control of breath alcohol concentration.
The UK legal limit for driving is 80 mg% in blood - this is equivalent to a breath alcohol concentration of 35 micrograms%.
The results from breath-testing can be used evidentially or for screening purposes.
Analysis
NIVHA uses fuel-cell based instruments (Lion Alcolmeters) which are accurate and dependable. Calibration is based on the use of a certified gaseous calibration standard and the procedures used follow good breathtesting practice guidelines.
