Good indoor air filters

Good indoor air quality (IAQ) depends on a number of factors,

including
• effective filtration,
which provides the primary defence for building occupants and HVAC equipment against particular pollutants. Today's higher standards in filtration, coupled with rigorous attention paid to filter selection and maintenance, helps to produce cleaner, purer air and reduce IAQ problems. Selecting
• HVAC air filters
based on the needs of the facility instead of simply their initial costs will lead to a review of filter efficiency as a determining factor. Air Filtration efficiency defines how well the filter will
• remove contaminants.
Low-efficiency air filters are typically used to keep lint and dust from clogging the heating and cooling coils of an HVAC system. Medium- and high-efficiency air filters are typically used to remove bacteria, pollen, soot, and other small particulates.

Selecting air filters

There are many types of HVAC filters on the market today: In most buildings, the best filter choice is a medium-efficiency pleated air filter, which has a higher removal efficiency than low-efficiency filters, and more adequately removes the particles that cause IAQ problems, unlike high-efficiency filters, which would clog. The pleated air filters used in HVAC systems are made with a wide range of materials (media), including fibreglass, polyester, cotton, paper, and synthetic non-woven materials. Recent advances in non-woven technologies have allowed for a step-change improvement in both performance and value of synthetic media over the standard cotton/poly blends used for years in HVAC filters.

Advantages of Synthentic media filters over traditional meadia filters

Unlike traditional cotton/poly media, the synthetic media in more modern filters can be made of thermally bonded, continuous hydrophobic (moisture-repelling) polyolefin fibres that resist shedding and do not absorb moisture. This is important in resisting bacterial growth, and it keeps shed fibres from getting into the HVAC coils or into the breathing air. Moreover, synthetic media can be manufactured without the use of chemical binders, meaning that humidity will not affect the web structure and will not cause the glue to soften and, thus, fibres to shed. Unlike cotton/poly filter media, which are made with a surface-loading structure, synthetic filter media can be made with a gradient density structure that provides a solid mechanical foundation to maintain high efficiency over the useful life of the filter