Since a few days, I am back to my previous laboratory to collect some more samples. While looking after my rats, I measured the noise level with a dBmeter. The conditions are:
- 8.30 am
- doors are left open (except in the housing unit) as it is usually the case
- five samples per room: one in each corner of the room (without moving any furniture) and one in the middle
- measures taken at ear height
- device: YF-20 (YFE)
The general mean is 61.7+/-3.3dB. But if we go into the details, a Kruskall-Wallis ANOVA shows most of the rooms have the same dB levels. But there is a significant statistical difference between the room where we perform experiments and the housing unit (p < 0.05). And there is a very significant statistical difference between the experiments room and the second office (p < 0.005). A significant statistical difference is also there between the two offices (p < 0.05; now guess in which one I am …).
Although very high compared to other labs, these levels are not considered as harmfull (same level as a busy restaurant – but you don’t stay 8hours a day in a restaurant). And anyway I am alway wearing ear plugs (3M 1100). On their box, it’s written they reduce noise level by 20-30dB.