The BIPM Kibble balance experiment is housed on a large concrete block in a closed cabinet inside a laboratory with an air conditioning system. The Kibble balance laboratory has two concrete foundations one for the Kibble balance (64 tonnes) and one for the gravimeter (10 tonnes). Each is isolated from the main floor of the building but remains in lateral contact with the earth to avoid low-frequency swinging motions (excited by surface Rayleigh waves). The horizontal and vertical rms velocities due to ground vibrations are respectively 1 µm s-1 and 0.76 µm s-1 (for frequencies between 0.003 Hz and 100 Hz).
|The Kibble balance laboratory|
A) concrete base for the Kibble balance (64 tonnes), isolated from floor;
B) concrete base for gravimeter (10 tonnes), isolated from floor