Low Background Counting Facility

SNOLAB HPGe Gamma Counters:

The SNOLAB Low Background Counting Facility offers gamma counting of materials using low background HPGe detectors. Different HPGe detectors at SNOLAB to screen materials for radioisotopes U, Th, K, Co-60, Cs-137 includes:

PGT Coaxial Detector (PGT)
Canberra Coaxial Detector (Lively)
Canberra Well Detector
Eurisys Mesures Coaxial Detector (Vue Des Aples)
Canberra Coaxial Detector (Gopher)

Details on the Detector properties and sensitivities can be found on Gamma Counting Facilities page.

Please visit the Assay Request Form page to request for gamma counting services.

Alpha Counting:

We perform measurements of surface alpha contamination in
materials using the XIA UltraLo-1800 alpha counter. The sensitivity
of the XIA alpha counter at SNOLAB in terms of emissivity is 0.00158±0.00011 alpha/cm²/h.

Specifications for sample:

Maximum sample weight: 9kg
Maximum sample thickness: 6.3mm

Please visit the Assay Request Form page to request for alpha counting services.

Radon Emanation Measurements:

We provide Radon emanation study of all construction materials for new, existing, and proposed experiments (to be located) at SNOLAB. We also provide services to experiments outside of SNOLAB around the globe. Sample materials are measured for ²²²Rn to ensure radiopurity. Two different techniques are employed at SNOLAB for Rn emanation studies:

Electrostatic Counter(ESC) Rn Emanation Study: ESCs are operated and maintained by Laurentian University at SNOLAB in support of the EXO Low Background screening and development program.

Radon Emanation Studies using Liquid Nitrogen Cooled Traps:
The Radon detection system includes a low radioactivity acrylic emanation chamber, a radon transferring board, and a low background Lucas scintillation (ZnS) cell. Radon in the sample material is trapped using a primary trap (The board has two liquid nitrogen cooled traps filled with Bronze wool and chromosorb wool to trap radon) and a secondary concentrated trap. In the final step, radon from the secondary trap is transferred to a Lucas cell, which is then alpha counted using photomultiplier tubes.

Please visit the Assay Request Form page to request for Radon emanation counting services.


SNOLAB currently operates low background facilities in the SNOLAB surface laboratories and in the deep underground laboratory at the 6800 ft level (6000 m.w.e.) of the Creighton Mine, which is located near Sudbury, Ontario, Canada.