(a)
(2) Each installation or activity must evaluate its situations against the guidelines issued by the Office of Personnel Management to determine whether the local situation is covered by one or more of the defined categories.
(b)
(2) An employee entitled to an environmental differential on an actual exposure basis shall be paid a minimum of one hour's differential pay for the exposure. For exposure beyond one hour, the employee shall be paid in increments of one quarter hour for each 15 minutes or portion thereof in excess of 15 minutes. Entitlement begins with the first instance of exposure and ends one hour later, except that when exposure continues beyond the hour, it shall be considered ended at the end of the quarter hour in which exposure actually terminated.
(3) An employee entitled to an environmental differential on the basis of hours in a pay status shall be paid for all hours in a pay status on the day on which he/she is exposed to the situation.
(4) An employee may not be paid more than one environmental differential for a particular period of work.
(5) The payment of environmental differential pay is computed on the basis of the highest environmental differential rate authorized during the period of entitlement.
(6) The number of hours an employee is paid environmental differential shall not exceed the number of hours of duty performed by the employee on the day of exposure except as required by paragraph (b)(3) of this section.
(c)
(d) The schedule of environmental differentials is set out as appendix A to this subpart and is incorporated in and made a part of this section.