Personal Mercury Monitor for Exposure Measurements

Personal Mercury Monitor for Exposure Measurements Project Summary Abstract Workers in the oil and natural gas industry are vulnerable to exposure to toxic mercury Hg vapor as a result of routine inspection and maintenance of equipment such as compressors and other process equipment that concentrate species of low volatility over time Exposure of workers to mercury is of concern in many other industries as well including the chlor alkali industry where mercury is used as an electrode gold and silver mining where these precious metals are extracted with mercury manufacture of fluorescent and other lamps dentistry etc The mercury monitors currently on the market are large and difficult to transport and operate in many of the settings where mercury exposure occurs As a result there is a great need for a personal mercury monitor to protect the health of industrial workers Mercury vapor concentrations are best measured by absorbance of the nm emission line of a low pressure Hg lamp the same method used for measurements of ambient ozone Compared to ozone however mercury detection is times more sensitive In preliminary work we modified our recently developed Personal Ozone Monitor POM for mercury concentration measurements This pocket sized instrument weighs only lb and consumes only watts of power In a proof of concept application earlier this year the modified POM displayed excellent precision for Hg of g m in field testing by a leading oil and gas company on their oil and gas production platforms in the North Sea during annual inspection and maintenance A problem discovered with this prototype instrument however is that the necessarily small internal mercury scrubber cm volume has very limited capacity due to the limited number of adsorption sites on the sorbent surface In order to solve the problem of limited scrubber capacity for Hg we propose to develop a photochemical mercury scrubber that photo oxidizes Hg in the gas phase to nanoparticles of HgO that pass through the instrument We have demonstrated and quantified this Hg scrubbing principle in laboratory experiments Advantages of the photochemical mercury scrubber include theoretically unlimited scrubbing capacity endowment of the personal mercury monitor with high selectivity against other UV absorbing species such as ozone NO and volatile aromatic compounds that may occur in industrial environments and elimination of any interference due to sudden changes in humidity With these advantages and our company s previous innovations in miniaturizing instruments for detecting airborne trace gases a breakthrough in technology for monitoring mercury exposure in the workplace is achievable The deliverable for this project if funded will be a pocket sized personal mercury monitor with precision and accuracy comparable to much larger fixed location monitors Deployment of the Hermes Personal Mercury Monitor will improve the safety of workers in all industries where exposure to mercury vapor is a potential hazard Project Narrative Workers in the oil and natural gas industry are particularly vulnerable to exposure to mercury vapor because of their proximity to its sources and maintenance requirements of equipment that often concentrates species of low volatility We will develop a new pocket sized personal mercury monitor that will allow workers to monitor their exposure to this neurotoxin in real time