23/05/2018

Breath alcohol control

Breath alcohol control. The meters must be calibrated to give evidence-safe results. Reference materials are used for calibrating and checking the measuring instruments.

Source: BAM

BAM has been producing certified reference materials for many years accumulating expertise difficult to obtain. BAM, together with partner institutes, now supports other national metrology institutes in Europe to develop this expertise and to produce high-quality reference materials for their own national markets. Here are two examples.

Traffic accidents are the leading cause of death among 5- to 29-year-olds in Europe according to a WHO 2015 study1. Alcohol plays a role in many road accidents, and this affects all age groups, but there are big regional differences. Statistics show that countries in Northern Europe on average score better than other European countries. The goal must be to minimise the number of traffic victims in all countries. But which measures work best? Risks can be reduced by good transport infrastructure, better traffic laws, traffic education, speed limits or controls.

Determining breath alcohol

Breath alcohol controls: police use them to pull drunken drivers out of traffic, road users fear them. The test is simple: people being controlled by the police give a breath sample, i.e. they blow into a measuring device. Evidential breath alcohol measuring devices have two sensors that independently measure the ethanol content in their breath. The meter finally outputs a result and if they get caught with too much alcohol in their breath, they must pay a fine or even surrender their driving license.

Measurement protocol of a device for measuring breath alcohol

Measurement protocol of a device for measuring breath alcohol

Source: BAM

Devices that can provide reliable, court-proof data must be calibrated. In Germany, breath alcohol meters must be checked every six months. The calibration process uses a reference material manufactured and sold by BAM. The International Organisation of Legal Metrology (OIML) defines the requirements in Recommendation R 126 and these are high. The reference solution must be stable, homogeneity must be characterised and there has to be a certificate available for each material. Before a solution is delivered, BAM checks the reference material again to make sure that it can produce correct readings.

Where is the problem? Dr. Rosemarie Philipp from BAM’s Environmental Analysis Division says: "BAM have been producing such reference materials for more than ten years. We do this mainly for the German market. We produce about 150 litres of these ethanol solutions per month, which is also our capacity limit. We would not be able to cover the entire European market with our materials." Thus the issue is enabling other national metrology institutes in Europe to produce high-quality reference materials that can then be used for breath alcohol measurements in their countries. One aims at the deterrent effect of controls, fines and driving license withdrawal for drunk drivers. To make this happen across Europe, ALCOREF was launched, a project under the European Metrology Program for Innovation and Research (EMPIR) with a total of ten European partners where BAM is the project leader.

Solve problems at the European level

There are also international projects in the environmental field that help other European countries to implement Europe-wide standards such as the ENVCRM project, which aims to develop matrix reference materials for environmental analyses. BAM’s Inorganic Trace Analysis Division participates as a project partner in this project. Dr. Philipp explains: "Let us take the European Water Framework Directive, for example which sets limiting values that apply across Europe. Monitoring requires common reference materials or national reference materials of comparable quality standards in each country. Germany is interested in environmental standards being adhered to in other countries because pollutant transfer does not stop at national borders, rather pollutants are further spread by rivers or the air and then pollute the environment in neighbouring countries." International problems need international solutions. Whether environment or road safety – it is about common standards and ultimately a better quality of life. BAM and other national European state institutes pass on their know-how in joint projects to those metrological institutes that want to harmonise their standards or, according to EU law, are compelled to.