Ventilation Issues Found In Majority Of California Classrooms With New HVAC Systems
DAVIS (CBS13) - Nearly 85 percent of HVAC units recently installed in California K-12 schools do not provide adequate ventilation, according to research done at UC Davis and the Berkeley Lab, and it is up to schools, not the state, to test for issues.
The study was conducted during the 2016-2017 school year and focused on 11 schools that installed new HVAC (heating, ventilation, and air conditioning) units within the past three years. The researchers evaluated the indoor temperature, humidity, and carbon dioxide concentrations in 104 classrooms for four weeks and found more than half had issues with hardware, fan control, and filter maintenance. Only 15 percent met the ventilation standard when measuring carbon dioxide concentrations.
As for temperature, about 60 percent of the classrooms involved in the study were warmer than the recommended average maximum temperature of 73 degrees. About a third of the teachers said they were dissatisfied with the temperature inside their classroom, with one in ten saying the temperature interfered "a lot with the learning environment."
California does have a Division of State Architect review process to make sure projects meet the 2016 Building Energy Efficiency Standards (Title 24). However, most replacement HVAC projects are exempt from the review process so schools are required to make sure the systems are in compliance.
The researchers did make a number of recommendations following the study, including replacing filters two to three times a school year, monitoring classroom carbon dioxide concentrations using sensors, and conducting ventilation rate testing.
The full study is being published in the Building and Environment journal.