The sample preparation laboratories of PCIGR are located on the 3rd floor of the EOS Main building, just below the roof. The three labs are completely independent in terms of air supply. They are accessed by a vestibule. The entire air-handling system is HEPA-filtered (total of 42 HEPA-filters), with two levels of pre-filtration. The labs were designed to achieve Class 1000 – all the measurements are close to Class 100. Each lab is equipped with two or three Class 100 laminar flow hoods. In each lab, one hood is an exhaust hood and the tracer lab is also equipped with a perchloric hood.
The three clean labs are divided according to specific analytical needs and the level of the required chemical processing: the tracer lab is devoted to “routine” Sr-Nd-Hf separation for isotopic studies, together with separation for heavy stable isotope studies; the U-Pb lab is only used for U-Pb zircon (+baddeleyite/monazite/titanite) chemistry and the low level tracer lab is devoted to low-level chemical analyses and preparations that have special requirements (ppm to ppb level).
Access to the labs is strictly limited to the users and requires complete gowning. Sample preparation, dish-washing, and bomb dissolution are carried out in the prep room, before taking only the cleanest necessary items into the chem labs. Two systems of high-capacity Elix/MilliQ water filtration are installed to provide ultra-clean water and all of the acids are either quartz-distilled or sub-boiled according to the needs. Our blank levels are accordingly excellent, in the 10-100 pg range for all the elements that we are dealing with. We carry out a bi-weekly monitoring of the cleanliness of all the reagents and the air quality of the labs.