Linearly related samples covering low to high and clinically significant levels.

Replicates samples repeat up to four times over 12 months, assists with trouble shooting and precision analysis.

Reference value assigned for key measurands derived from JCTLM registered laboratories.

Patient / donor samples (toxicology, porphyrins, serology / immunology).

Lyophilised samples; prepared on site (independent of commercial deliveries); designed to reflect what participants are likely to find in routine specimens in their laboratory; suitable for various methods.

Simulated environmental samples that challenge testing platforms used for the detection for select and security sensitive biological agents.