Members of any board established under this section who are otherwise employed by the Federal Government shall serve without compensation but shall be reimbursed for travel, subsistence, and other necessary expenses incurred by them in carrying out its duties under this section.

Members of any board established under this section who are not subject to paragraph (1) shall receive compensation at a rate prescribed by the Director but not to exceed the daily rate prescribed for GS–18 of the General Schedule under section 5332 of title 5, including travel for each day they are engaged in the performance of their duties under this section and shall be entitled to reimbursement for travel, subsistence, and other necessary expenses incurred by them in carrying out their duties under this section.