The Regulations do not specify the method of conducting the health assessment. It might be conducted by a qualified medical practitioner, but it could consist of a health questionnaire assessed by a health professional, such as a nurse.
The purpose of the assessment is to identify any factors that might be detrimental to the health of a worker as a result of night work, in which case he or she is entitled to be transferred to suitable day work where this is possible. In such a situation, the Regulations provide that a 'registered medical practitioner' must have advised the employer that the worker is suffering from health problems that the practitioner considers to be connected with the performance by that night worker of night work.