Principle 1
Analytical measurements should be made to satisfy an agreed requirement.

Principle 2
Analytical measurements should be made using methods and equipment which have been tested to ensure they are fit for purpose.

Principle 3
Staff making analytical measurements should be both qualified and competent to undertake the task.

Principle 4
There should be a regular independent assessment of the technical performance of a laboratory.

Principle 5
Analytical measurements made in one location should be consistent with those elsewhere.

Principle 6
Organisations making analytical measurements should have well defined quality control and quality assurance procedures.