Royal International Inspection Laboratory RIIL provides proficiency tests to other labs for many purposes:

• Evaluation of the performance of the laboratories for specific tests or measurements and monitoring laboratories' continuing performance
• Identification of problems in laboratories and initiation of actions for improvement which, for example, may be related to inadequate test or measurement procedures, individual staff performance or calibration of equipment.
• Establishment of the effectiveness and comparability of test or measurement methods.
• Provision of additional confidence to laboratory customers
• Identification of inter-laboratory differences
• Education of participating laboratories based on the outcomes of such comparisons
• Evaluation of the performance characteristic of method-often described as collaborative trials
•  Assignment of values to Reference Materials and assessment of their suitability for use in specific test or measurement procedures