Where applicable, the respect of the requirements and standards shall be determined by the use of means as stipulated in the legislation applicable to the requirement or standard in question.

In other cases and where appropriate, the determination shall be carried out by the use of any appropriate means defined by the competent control authority which ensure precision at least equivalent to that required for official determinations under the national rules.

Where appropriate, the on-the-spot checks may be conducted by the application of remote-sensing techniques.