7.—(1) In this Part—

“agency worker” means an employee whose contract of employment is of the kind mentioned in paragraph (b) of the definition of “contract of employment” in section 3;

“associated employer” shall be construed in accordance with subsection (5);

“comparable employee” shall be construed in accordance with subsection (2);

“full-time employee” means an employee who is not a part-time employee;

“normal hours of work” means, in relation to an employee, the average number of hours worked by the employee each day during a reference period;

“part-time employee” means an employee whose normal hours of work are less than the normal hours of work of an employee who is a comparable employee in relation to him or her;

“reference period” means a period which complies with the following conditions:

(a) the period is of not less than 7 days nor more than 12 months duration,

(b) the period is the same period by reference to which the normal hours of work of the other employee referred to in the definition of “part-time employee” in this section is determined, and

(c) the number of hours worked by the employee concerned in the period constitutes the normal number of hours worked by the employee in a period of that duration;

“relevant part-time employee” shall be construed in accordance with subsection (2).

(2) For the purposes of this Part, an employee is a comparable employee in relation to the employee firstly mentioned in the definition of “part-time employee” in this section (the “relevant part-time employee”) if—

(a) the employee and the relevant part-time employee are employed by the same employer or associated employers and one of the conditions referred to in subsection (3) is satisfied in respect of those employees,

(b) in case paragraph (a) does not apply (including a case where the relevant part-time employee is the sole employee of the employer), the employee is specified in a collective agreement, being an agreement that for the time being has effect in relation to the relevant part-time employee, to be a type of employee who is to be regarded for the purposes of this Part as a comparable employee in relation to the relevant part-time employee, or

(c) in case neither paragraph (a) nor (b) applies, the employee is employed in the same industry or sector of employment as the relevant part-time employee is employed in and one of the conditions referred to in subsection (3) is satisfied in respect of those employees,

and references in this Part to a comparable full-time employee in relation to a part-time employee shall be construed accordingly.

(3) The following are the conditions mentioned in subsection (2)—

(a) both of the employees concerned perform the same work under the same or similar conditions or each is interchangeable with the other in relation to the work,

(b) the work performed by one of the employees concerned is of the same or a similar nature to that performed by the other and any differences between the work performed or the conditions under which it is performed by each, either are of small importance in relation to the work as a whole or occur with such irregularity as not to be significant, and

(c) the work performed by the relevant part-time employee is equal or greater in value to the work performed by the other employee concerned, having regard to such matters as skill, physical or mental requirements, responsibility and working conditions.

(4) If the relevant part-time employee is an agency worker then the application of subsection (3) shall not result in any employee, other than another agency worker, being regarded, for the purposes of this Part, as a comparable employee in relation to him or her (and likewise, if the relevant part-time employee is a non-agency worker, the application of that subsection shall not result in an agency worker being regarded, for the purposes of this Part, as a comparable employee in relation to the relevant part-time employee).

(5) For the purposes of this Part, 2 employers shall be taken to be associated if one is a body corporate of which the other (whether directly or indirectly) has control or if both are bodies corporate of which a third person (whether directly or indirectly) has control.