We report low-frequency resistance fluctuation (noise) measurements in semiconducting and metallic Ti/Au-contacted single-wall carbon nanotube devices. In both types of devices, the noise power spectra has a "1/f" dependence, and is proportional to the squared current. Semiconducting devices were found to have three orders of magnitude higher noise levels compared to the metallic ones. In vacuum, the resistance increases but noise decreases by over an order of magnitude for both metallic and semiconducting devices. The resistance and noise levels recover to their original values when the samples are brought back to atmospheric pressure. Both noise and resistance change simultaneously when the chamber is evacuated. However, when the chamber is brought back to atmospheric pressure, the noise level takes several tens of hours longer to recover.
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