"clean room produces less than half the noise of any rival facility – 30dB versus 65dB.
Uh? 30dB ≠ ≈ half 65dB. And I'll ignore the confusingly placed dash.
Anyway, '65dB' relative to what. And does it refer to sound or EMR/RF? They are different you know.
Presumably, '65dB' refers to nominal/ambient sound level, if so then 30 dB down on that isn't much if the anechoic chamber is state of the art. And what frequency/range of frequencies does this apply to?
Perhaps 30dB versus 65dB actually means 'anechoic chambers typically attenuate 65dB and this one is better by another 30dB'. If so, then it would be truly a state-of-the-art facility.
If it's EMR/RF then again the figures make no sense. The EMR/RF attenuation of Faraday cages is measured in dB relative to background radiation and specified across bands of frequencies. So what are those frequencies?
If the Faraday cage attenuated some 65 dB down on background then this is good figure but it's hardly state of the art (unless that limit is determined by radiation from plant and equipment being used within the cage).
Incidentally, dB is a logarithmic ratio. Here's a very shortened precis from the Wiki defn.
The number of decibels is ten times the logarithm to base 10 of the ratio of the two power quantities.
This article left me not much the wiser.