Safeguards Analytical Laboratory
IAEA Clean Laboratory for Safeguards
Since 1996, the IAEA has been implementing environmental sampling for Safeguards as a strengthening measure designed to detect clandestine or undeclared nuclear activities in countries subject to full-scope safeguards.
The Clean Laboratory for Safeguards was inaugurated in December, 1995 with the goal to provide a Class-100 clean-room capability for the provision and certification of environmental sampling kits and for the receipt, screening and distribution of environmental samples coming from safeguards inspections. This facility for clean handling of sampling materials and samples significantly reduces the risk of cross contamination which might lead to incorrect safeguards conclusions. The Clean Laboratory consists of over 200 m2 of laboratory space, with approximately 100 m2 at Class-100 cleanliness level. The laboratory is equipped with state-of-the-out analytical techniques as described below.
Environmental swipe samples are received at the Clean Laboratory and are given a code number to maintain confidentiality about their origin. The samples are then measured by low-background gamma spectrometry to detect the presence of actinide elements (primarily U and Pu) and fission or activation products (such as 60Co, 137Cs, 106Ru, etc.); the samples are then measured by radioisotope-excited X-ray fluorescence spectrometry to detect the presence of U, Pu or other important elements. Alpha/beta counting is then applied to the samples to detect actinides or beta-emitting isotopes such as 3H, 90Sr or 99mTc. Scanning electron microscopy is used to examine small particles removed from environmental samples. The size and morphology of these particles can be examined at high magnification and their elemental composition can be measured with X-ray fluorescence spectrometry using the electron probe attachment.
Following the screening measurements, sub-samples are distributed to laboratories of the IAEA Network of Analytical Laboratories (NWAL) for more detailed analyses. Selected samples are chosen for measurement in the Clean Laboratory by isotope dilution thermal ionization mass spectrometry, using a highly-sensitive instrument equipped with pulse-counting detection. The ultimate sensitivity of this method is in the femtogram range (10-15 grams) for U and Pu.
One of the main activities of the Clean Laboratory is the preparation of clean sampling kits for collecting environmental samples. A kit for the collection of swipe samples consists of all the supplies needed by an IAEA inspector in the field; clean swipe cloths, plastic minigrip bags, cleanroom gloves, the sample data form, pen and labels.
Cotton swipe kit for environmental sampling
A different type of swipe sampling kit is also provided for sampling inside hot cells, where the subsamples must be taken with remote manipulators and shipped back to the IAEA in a special lead-lined can because of their higher radiation level.
Analyst working in Clean Module