The operational philosophy of the BM Front End is the same as that for the ID Front End. The FE components are functionally equivalent but of differing design. This is because the power and the power densities that are handled by various components in the BM Front End are significantly smaller. Hence, the engineering of the BM components is less challenging.

Reference TB-5 explains several nuances regarding the placement of components in the BM Front End. This is of little significance to the FC and operations. One note of interest is that the vacuum pipe in the BM Front End is normally six inches in diameter and increases to eight inches in diameter at the location of the window outside the ratchet wall. The large size of this vacuum line coupled with the simpler component designs due to the lower heat loads on the BM line does not afford an intrinsic vacuum delay in the BM front ends. Hence, the large size of the BM vacuum line is used to fashion a delay tank in an unused two-meter portion of the vacuum transport by inserting eight baffles with apertures. In contrast, the ID Front End is expected to provide good vacuum delay because of the engineered and intrinsic ample aperture in the ID Front End.