The Canadian Certified Reference Materials Project announces the availability of reference uranium tailings sample UTS‐1, ‐2, ‐3 and ‐4. Eighteen laboratories participated in the interlaboratory program for total iron, titanium, aluminium, calcium, barium, uranium, thorium, total sulphur, sulphate and arsenic. Eight laboratories participated in the inter‐laboratory program for thorium‐230, radium‐226, lead‐210 and polonium‐210 in all four samples and for thorium‐232, radium‐228 and thorium