Public Workshop #2 on Updating the Indoor Air Quality Guidelines for Nitrogen Dioxide
Categories
Public Workshop
Purpose of Workshop
CARB is evaluating the health evidence and approaches for updating California's indoor air quality guidelines for NO2 to protect public health. Based on information presented at the first NO2 guidelines workshop held in May 2023 and previous work by other guideline developing health agencies, CARB has identified possible approaches for updating its indoor NO2 guidelines. For each approach, we are considering the development of both 1-hour and 24-hour guidelines to cover acute and chronic exposures. CARB will present options, which include developing or adopting scientifically based 1-hour and 24-hour values from existing IAQ guidelines that have undergone public review and analysis or developing new guideline values based on an evaluation of recent scientific literature and health data not previously considered. After the presentation, CARB will open the meeting for comment and discussion. Our objective is to get feedback on the proposed approaches, their relative strengths and weaknesses, technical issues, and input on health protectiveness and feasibility.
Background
CARB’s existing 2005 indoor air quality guidelines for NO2 and other pollutants were developed as part of the 2005 Indoor Air Quality Report to the Legislature. They were based upon CARB’s outdoor standard for a 1-hour averaging time, and WHO’s indoor guideline for a 24-hour averaging time. These guidelines were one of the first efforts to provide information on safe levels for air pollutants indoors. Since the 2005 report, numerous studies have been published about the health effects of NO2. Other agencies, most notably Health Canada and WHO, have continued to update their indoor guidelines and adopt lower indoor pollutant levels to protect public health. The most recent Health Canada and WHO guidelines for indoor NO2 levels are significantly lower than CARB’s current NO2 guideline levels and support the need to reevaluate CARB’s indoor air guidelines.
Contact
If you have questions regarding this workshop, please contact Jeffery Williams in CARB’s Research Division at Jeffery.williams@arb.ca.gov.
If you require a special accommodation or need this document in an alternate format (i.e., Braille, large print) or another language, please email Jeff Williams as soon as possible, but no later than ten business days before the workshop. TTY/TDD/Speech to Speech users may dial 711 for the California Relay Service.