Mercury analyzer RA-915 light is a low cost analytical instrument for measuring mercury concentrations in air. It is intended for assesment of indoor/outdoor air quality in residential and industrial settings. Mercury is among most abundant environmental pollutants which adversely affects ecological systems and human beings. It shows high toxicity, mobility, and ability of accumulation in trophic chains of water and continental biocenosis. Therefore, it is recognized to be one of the most hazardous global environmental pollutants.