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 higher the MERV rating, the higher the effectiveness of the air filter Microparticle Performance Rating, or MPR for short, is a filter rating system developed by 3M to rate a filters ability to cature the smallest airborne particles. The higher the MPR rating the better the filters ability to capture particles from the air.