Shield bonds

At joints in the shield and where access doors are necessary, continuous electrical and mechanical bonds are required. Therefore, the joints should be permanent where possible (by welding or brazing) or semi-permanent with good, clean, machined metallic surfaces bolted together with a radio-frequency (rf) gasket between them. The rf gasket will ensure continuous low-impedance contact throughout the joint. Bonding straps of copper or braid may be used where direct bonds are not possible, and these function reasonably well at lower frequencies. However, this type of bond is never as good as a direct bond. In general, since a low impedance path between points is required, it can be accomplished only when the path length between the points is short in comparison with the wavelength being rejected.