N.R. Murphy offers high efficiency filters among its many products

High efficiency filters are available from N.R. Murphy.

Known as a producer of dust-collecting equipment and fans, N.R. Murphy Ltd. is also a top source for high efficiency filters. These filters are among the key components that workplaces often require to ensure that indoor air is clean and safe.

High efficiency filters are recommended for applications that require extremely efficient filtration, particularly for employers that need very clean working environments.

A variety of sizes available

N.R. Murphy supplies absolute high-efficiency particulate air filters, or HEPA filters. This is a kind of mechanical air filter that operates by forcing air through a fine mesh that traps pollen, pet dander, dust mites, tobacco smoke, and other harmful particles. These filters are manufactured, tested, certified, and labelled according to current HEPA standards.

High efficiency filters by N.R. Murphy are more than 99.97 per cent efficient for particles measuring as small as 0.3 microns, and they approach an efficiency of 99.97 per cent for smaller particles. The company recommends them mostly for the chemical industry and in precision assembly areas.

Most installations of these filters require intermediate or high-efficiency prefilters upstream of the absolute filter, to keep most dust away and to prolong the absolute filter’s life as much as possible. Companies could use these prefilters on their own, although this would decrease the filtering efficiency by about 95 per cent with particles of 0.3 microns in size.

To give clients an idea of the relative sizes of common air contaminants, N.R. Murphy has included a handy chart on its website, illustrating the differences. According to the chart, the company’s high efficiency filters can eliminate substances as varied as dusts, fumes, pollen, bacteria, molds, viruses, and oil and tobacco smoke from air.

High efficiency filters are available in a variety of sizes, most commonly two square feet and ranging from seven to 12.5 inches deep, with airflow capacities from 200 to 2,000 cubic feet per minute. Depending on airflow capacity, the filters are usable individually or in series. N.R. Murphy can also supply holding frames and side entrance housings, with flanges for easy attachment to ductwork.

To learn more, contact N.R. Murphy.

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