Let’s talk indoor air quality… Combining work and home, people spend approximately 90% of their time indoors. Indoor air quality is about the health and well-being of a building’s occupants and visitors. The HVAC industry is all about improving and maintaining air quality. It’s not a matter of pure indoor air, but providing quality air at an affordable cost.
According to a Cornell University Study on the Cause of Poor Indoor Air Quality (IAQ). Poor indoor air quality can lead to…
- Dry mucous membranes and skin
- Erythema (reddening or flushing of the skin); rashes
- Mental fatigue, headache, and sleepiness
- Airway infections, cough
- Hoarseness, wheezing
- Nausea, dizziness
- Unspecific hypersensitivity reactions
The skeptical hypochondriac is right now stating “these symptoms are common to a myriad of other issues.”
That is correct! However, if a building’s occupant develops symptoms several hours after entering work, and feels better after leaving the building during evening hours, weekends or a vacation, there may be a valid concern.
Although many of these symptoms may be caused by other health conditions, or allergies; including the common cold or flu, poor IAQ may worsen matters, and make diagnosing or identifying the source of an illness more difficult. For those who love acronyms, here is a myriad of names for buildings with poor IAQ … Sick Building Syndrome (SBS), Tight Building Syndrome (TBS), Building-Related Illness (BRI) and Multiple Chemical Sensitivities (MCS).
Poor IAQ ranges from pollutants given off by a building or furnishing materials, cleaning products, office machines, and pesticides to name a few. As HVAC professionals, we must concern ourselves with providing adequate fresh air, ventilation system design & maintenance.
Where building ventilation is inadequate, the resulting low air exchange rate is such that insufficient fresh air brought into a building does not dilute or flush out contaminants, and can become concentrated within a building.
Quality indoor air is not a 100% pure air requirement, but a request for indoor air which is not significantly worse than the air outside (assuming outdoor air quality meets EPA standards or the like).
MicroMetl Corporation is an industry leader in providing HVAC equipment and accessories. The intent of this site is to inform readers of our products, and general product functionality, by offering direct and indirect HVAC industry related topics. Before attempting to work on any Electrical or Mechanical equipment, always consult local building codes and all applicable local, state, and/or federal laws. We further urge you to contact only licensed, trained and certified HVAC personal, engineers, electricians, etc. MicroMetl is not liable or responsible for any errors, omissions, or inaccurate information provided.
High CO2 Levels
Overturning decades of conventional wisdom, researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have found that moderately high indoor concentrations of Carbon Dioxide (CO2) can significantly impair decision-making.
… On nine scales of decision-making performance, test subjects showed significant reductions on six of the scales at CO2 levels of 1,000 parts per million (ppm) and large reductions on seven of the scales at 2,500 ppm. The most dramatic declines in performance, in which subjects were rated as “dysfunctional,” were for taking initiative and thinking strategically. “Previous studies have looked at 10,000 ppm, 20,000 ppm; that’s the level at which scientists thought effects started,” said Berkeley Lab scientist Mark Mendell, also a co-author of the study. “That’s why these findings are so startling.”
Department of Energy’s Lawrence Berkeley National Laboratory
The primary source of indoor CO2 are us humans. While typical outdoor concentrations are around 380 ppm to 500 ppm, indoor concentrations can go up to several thousand ppm if not properly ventilated.
If Improper Air Ventilation is suspected… What Can Be Done?
The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) publishes ANSI/ASHRAE Standard 62.1-2013 – (Ventilation for Acceptable Indoor Air Quality) to allow HVAC professions to implement and maintain quality indoor air.
Here are a few HVAC Accessories to assist with compliance toward the ASHRAE standard.
Outside Air Hoods – Air flow often set with a damper to allow outside air to enter your rooftop unit. They are initially economical, but waste energy by causing your rooftop unit to remove humidity if present, and to condition the full brunt of whatever outside air temperature is present.
Economizer – Economizers are as implied… economical! Economizers contain controls which will intelligently control the volume of outside air, allow Free Cooling, and often contain a Barometric Relief to prevent over pressurization.
Energy Recovery Ventilation Units (ERV) – A larger upfront cost with the best long term payback. An ERV allows fresh air into a building, while retaining pre-conditioned heating or cooling, can double as a Power Exhaust, and can be configured to permit Free Cooling if desired.
CO2 Detection – A CO2 Detector can be connected to an Economizer, or ERV allowing the quantity of outside air to proportionally increase as the occupancy increases (On Demand), removing CO2 accordingly.
Indoor air quality requires very specific solutions which often must be tailored to specific needs. Feel free to contact your MicroMetl Representative, or our Customer Service Department with any of your HVAC Accessory Requirements!