The article is based on an experimental device performing quantitative analysis of alcohol vapors from exhaled air (breathalyzer), developed at the Technical University of Cluj-Napoca, called alcoholmeter. The reliability research is conducted over the nine components of the alcoholmeter, in terms of reliability indicators. The features selected and analyzed within the Relex Software Architect environment. Failure rates for each component and the reliability for the alcoholmeter prototype were determined. Also, the component failure rates were ranked and then a graphical representation of all components of the system has been built, based on the calculations results.