Mercury Analyzers: Total (THg) and Organic (MHg) Brooks Rand Instruments comes from a long tradition of commitment to advancing the accurate, reliable identification and measurement of trace metals. As the offspring of Brooks Rand Labs, the nation’s first and foremost provider of low-level mercury and methylmercury analysis, our company has a unique understanding of our customers’ needs. We know first-hand the day-to-day concerns and challenges faced by those who operate commercial and academic labs.