What are the standards for indoor air quality?
Understanding each of the factors contributing to the indoor environment is crucial to maintaining the health and safety of building occupants. Each factor is, in itself, a broad set of issues. In total, they contain the formula for a healthy, productive environment.
Indoor air quality criteria are measured by the following key categories:
- Relative Humidity
- Outside Air Ventilation
- Carbon Dioxide Levels
- Air Filtration
Relative humidity refers to the amount of moisture present in the air. Too much moisture and mold growth could become an issue. Too little moisture and occupants could experience dry skin and a greater risk of infection or illness.
There are several visual indicators of excessive moisture. Condensation on windows and wet stains on ceilings or walls can indicate that moisture levels are too high. Dry skin, sore throats, and static shocks are common signs of too little moisture in the air. To be most accurate in determining levels, it is recommended to use a relative humidity sensor or hygrometer.
Outside Air Ventilation
In this instance, outside air refers to the amount of outside air circulating within a building. This can be measured by an airflow sensor and remedied with proper ventilation equipment. Ensure that unit ventilators aren’t blocked, air filters are in proper working order, and that they are effectively bringing in outside air.
Carbon Dioxide Levels
Often, tight building envelopes and poor ventilation/filtration lead to elevated CO2 levels. As a result, high levels of CO2 often cause impaired cognitive abilities for building occupants. To measure CO2 levels throughout your building, take a CO2 monitor through each room of your building, holding it in the center of each room to get a proper reading. Buildings must be occuped to receive the most accurate CO2 readings.
Air filters are the most popular strategy for improving indoor air quality. Air filters are designed to collect solid particulates in the air that circulate through the heating and cooling system of a building. The most common particles they collect include dust, pollen, hair, animal fur, mold, and bacteria.
Air filters are rated by their performance and efficiency and given a minimum efficiency reporting value, or MERV rating. A higher MERV rating indicates better filtration. While it may seem best to have a higher MERV rating, high MERV ratings can interfere with heating and cooling effectiveness throughout a building so it is best to right-size your air filters for your HVAC system.
While indoor air quality is important, Performance Services recommends taking a holistic view when evaluating the indoor environment and occupant comfort. Lighting, acoustics, and temperature should not be overlooked as they too play a significant role in the focus and performance of building occupants.