The imaging equipment must meet the requirements regarding noise levels in operating mode, described in Blue Angel (the German Ecolabel), Office Equipment with Printing Function DE-UZ 205 (2017) or DE-UZ 219 (2021), section 3.51.
The stated A-weighted sound power level, LWAd, must be tested according to ISO 7779. The sound power level shall not exceed the limit value according to the following formula:
LWA,lim = 47 + 15 * lg ( SM/F + 10) dB
SM = page throughput in monochrome mode
SF = page throughput in colour mode
The stated A-weighted sound power level, LWAd, is calculated as follows:
LWAd =LWA1 + 3.0 dB
1Note that the calculation formula in DE-UZ 219 has been changed and made more stricter.