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.
Integrating Sound Level Meter. In atmospheric sounding and noise pollution, ambient noise level (sometimes called background noise level, reference sound level, or room noise level) is the background sound pressure level at a given location, normally specified as a reference level to study a new intrusive sound source.