top of page

What is "Air Flush"?

Clearing the Air: The Importance of Efficient Indoor Airflow

With the increase in concern for the rapid spread of viruses, implementing measures such as an Air Flush can help ensure airborne contaminants are mitigated.


Air flush is the process of increasing outside air ventilation for a period of time to replace indoor air with fresh air to improve overall quality. Per code, there is a minimum amount of outside air that is required to be brought into a building, and in certain areas like restrooms and janitor closets, there is a certain amount of exhaust that is needed. To achieve an air flush, the HVAC system can bump up the outside air to exceed what it normally provides. Sizing the equipment is necessary for the system to be able to handle an increased air flush. In new buildings, the system can be sized to bring in more outside air. In older buildings, a refurbishment of the equipment, such as a louver or coil replacement, is often needed so that the system has the capacity to bring in more outside air.

Most of the time, a building's HVAC system's outside air intake capacity is running at a code minimum level. Most units are capable of handling more outside air than the code minimum. "For example," says Michael Peterson, Senior Mechanical Designer, "The system can be programmed to bring in 25% outside air rather than 15%. Modifying the sequence of operations on the controls side can allow the user to program the system to, in the middle of the night, when it’s 85 degrees, open up the system and allow fresh air to flush in for two hours. This can be done automatically through the building management system."


Air flush is beneficial for multiple reasons. First, air flush can help remove any viruses or illnesses being circulated around, and in high occupancy buildings like schools, there is an increased amount of CO2 that is being breathed in and out by the occupants. An excessive amount of CO2 can cause various negative health effects such as headaches, dizziness, tiredness, difficulty breathing, and difficulty focusing. It is important that measures are taken to ensure sufficient air quality to mitigate any viruses or contaminants that are easily spread through the air. The quality of the air we breathe must continue to be a top priority in any building in which we live, work, and play.










Legal Disclaimer: All information contained in this article is provided for informational purposes only and should not be construed as professional, engineering, financial, real estate, tax, or any other type of advice. The information and opinions contained in this article reflect only the personal opinions of the author of the article, and are not the professional opinions of TJK Consulting Engineers, Inc. (“TJK”). The use of any information in this article for any purpose will be at the reader’s sole risk and without liability to TJK or the author of the article. TJK does not represent or warrant that the information contained in this article is accurate as of any particular date and notes that rules, regulations, codes, and procedures are constantly changing and evolving. TJK undertakes no obligation to confirm the accuracy or completeness of this information as of any particular date and TJK makes no representation that this information will be current or up to date as of the date the reader is reading it. The reader (i) acknowledges and agrees that there is no substitute for consultation with a licensed, qualified professional that can take into consideration all relevant facts and circumstances for the reader’s specific needs, and (ii) understands that no professional-client relationship exists between TJK and the reader without signing all of TJK’s engagement materials and agreements. All regulatory and governing bodies having jurisdiction over a particular matter or project should be consulted to ensure that all applicable and up-to-date rules, regulations, codes, and procedures are being followed.

Comments


Commenting has been turned off.
bottom of page