Download or read book Method of Testing General Ventilation Air-cleaning Devices for Removal Efficiency by Particle Size written by American Society of Heating, Refrigerating and Air-Conditioning Engineers and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically, standards for testing air cleaners have been developed in response to the needs of the times. Protection of machinery and coils came first, then reduction of soiling. Now concerns about indoor air quality and respirable particles, protection of products during manufacturing, and protection of HVAC equipment have prompted development of this test standard based on particle size ... This standard addresses two air-cleaner performance characteristics of importance to users: the ability of the device to remove particles from the airstream and its resistance to airflow ... A sample of air from a general ventilation system contains particles with a broad range of sizes having varied effects, sometimes dependent on particle size. Coarse particles, for example, cause energy waste when they cover heat transfer surfaces. Fine particles cause soiling and discoloration of interior surfaces and furnishings as well as possible health effects when inhaled by occupants of the space. When air cleaners are tested and reported for efficiency in accordance with this standard, there is a basis for comparison and selection for specific tasks. The test procedure uses laboratory-generated KCl particles dispersed into the airstream as the test aerosol. A particle counter measures and counts the particles in 12 size ranges, both upstream and downstream, for the efficiency determinations. This standard also delineates a method of loading the air cleaner with synthetic dust to simulate field conditions. A set of particle size removal efficiency (PSE) performance curves at incremental dust loading is developed and, together with an initial clean performance curve, is the basis of a composite curve representing the minimum performance in each size range. Points on the composite curve are averaged and the averages are then used to determine the minimum efficiency reporting value (MERV) of the air cleaner. Coarse air cleaners may be tested for particle size removal efficiency when they are clean, with results reported in the prescribed format. (An example of a coarse air cleaner is the so-called “furnace” filter, a flat panel with a cardboard frame and spun glass fiber media.) However, the standard also provides the basis for evaluation using the loading dust efficiency by weight, or “arrestance,” as well as an estimate of predicted life called “dust holding capacity.”--Foreword, page 2.