Detailed answer regarding Ceiling Fan Direction. During the summer, you want the air blowing directly on you so you will feel cooler from the wind chill effect (which is how fans cool you off). So stand under the fan and turn it up on high speed.
NRR STANDS FOR NOISE REDUCTION RATING. NRR (noise reduction rating) is a single number rating method which describes a hearing protection device (HPD) based on how much the overall noise level is reduced by the HPD. Most noise measurements in the industry are derived from the A-weighting scale.
THE CONCEPT OF CNR. CNR is in cable industry vernacular a pre-detection measurement-that is, a measurement performed in the frequency domain. By definition, CNR is the difference, in decibels, between the amplitude of an RF signal and the amplitude of noise present in the transmission path of the RF signal. The RF signal may be unmodulated (also called continuous wave, or CW) or modulated.