ABSTRACT
The Environmental Protection Agency has published two methods for sampling and analyzing mercury in gaseous and particulate emissions in conjunction with publication of National Emission Standards for Hazardous Air Pollutants. In the sampling of mercury and its compounds from the air, two basic procedures are available. These procedures utilize either the chemical reactivity of the sampled components in various aqueous media or the extraordinarily efficient extraction of mercury from air by the noble metals. A number of less laborious methods of sampling mercury vapor, compounds, and particulates have been developed which utilize absorption of vapor on silver and gold and on alloys of these materials. Use of silver on charcoal absorbent is highly efficient and may be used to remove mercury vapor from many gas streams. A wide variety of methods have been developed to measure airborne mercury-containing materials in the atmosphere based on the strong absorption of ultraviolet light at 253.7 nm by elemental mercury vapor.
