Article
John P. Lapotaire, CIEC
How Important is Humidity for Indoor Air Quality IAQ
The New Webster’s Dictionary defines air conditioning as: “The process of regulating the quality, temperature, humidity, and circulation of air in a space enclosure.” These are the criteria for basic comfort management for the occupants within the modern office environment. The designer, building owner, or management company who disregards this is opening the doors to litigation which will be much more costly than any savings assumed to be created by not maintaining proper indoor comfort conditions.
The premise behind the concerns for IAQ and IEQ are the comfort and well-being of the occupants within the workplace. The modern workforce has changed, with increased numbers of highly skilled and talented employees in the close confines of the office place. Losses in productivity within this workforce can be extremely expensive to the employer and requires new thinking regarding the work environment.
Thermal comfort is a main component of IAQ and IEQ and has been shown to be the primary concern of occupants in many studies. The low cost of addressing a thermal comfort condition can be greatly exceeded by the expensive losses created by increased illnesses, discomfort, absenteeism and poor productivity. Health care costs are also skyrocketing, adding to the expenses of the employer and the desire to avoid preventable health issues.
In warmer climates and weather conditions, the acceptable indoor conditions can usually be attained through a properly designed hvac system, which will ventilate the space and heat, cool, dehumidify, and filter the air distributed into the space. Maintaining the desired 50% to 60% rh indoors is easily accomplished with the typical hvac system during this period.
The introduction of dry outside air through the ventilation system in colder weather can reduce the indoor relative humidity to subarid conditions as low as 3%. The low humidity causes the occupants to feel chilled and uncomfortable and also causes increased susceptibility to colds; flu; pneumonia; dry skin; dry itchy eyes; and contact lens irritation.
Absenteeism in the workplace is much more prevalent during colder weather due to the above causes. It costs the employers billions of dollars in salary and productivity losses annually. The installation of a humidification system designed to maintain 35% to 45% rh during colder weather is highly recommended to maintain proper comfort and well-being of the occupants. The benefits gained in increased productivity and reduced absenteeism will allow a return on investment within a very short period of time. Humidity control in the modern office space is essential to IAQ and IEQ.
Berlin is a member of ASHRAE, chairman of ASHRAE SPC164P, and chairman a/the humidifier section’s engineering committee of ARI (Air-Conditioning and Refrigeration Institute) He is vice president of marketing and sales of Nortec Industries Inc. (Ogdensburg, NY) and has over 35 years’ experience in the design and marketing of residential, industrial, and commercial humidification systems.
•John P. Lapotaire, CIEC•Certified Indoor Environmental Consultant•Microshield Environmental Services, LLC• www.Microshield-ES.com
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