Rationale

The current wording in section 12 Period of Exposure is sometimes interpreted by users or accrediting bodies in a way that causes confusion on how to handle test interruptions in relation to period of exposure. Although section 12 is clear with its mandatory language that B117 does not define the period of exposure, there is still the question of how to handle the time used for test interruptions due to examining samples, rotating samples, collection rates or other such issues. It is proposed to add wording to note 15 to further clarify the issue