Environmental Health & Safety

Indoor Air Quality During Smokey Conditions

The UC Riverside campus has dozens of buildings and each building performs differently based on its design, age, equipment, and critical human factors.

"It Smells Smoky in Here..."

We can't stress enough the importance of keeping doors and windows closed when it's smoky outdoors. Indoor air will commonly smell of smoke during a wildfire event, but when we test it, we find it’s consistently better (i.e., containing lower particulate matter) than being outdoors. Most buildings contain MERV-rated filters that reduce harmful particulate pollution, but do not have charcoal filters that eliminate odors.

Facilities Services’ Role During a Smoke Event

Facilities Services is responsible for maintaining critical air-conditioning and ventilation systems throughout the year. Their teams are incredibly busy on hot and smoky days monitoring HVAC performance. Air filters are replaced on a schedule throughout the year, but Facilities Services will monitor filters during and after a prolonged smoke event and change as needed. 

Learn more about ventilation in buildings on the Facilities Services website. 

Employees with indoor air quality concerns can:

Contact Facilities Services: 

Report an indoor air safety concern to EH&S:

Please note, staff are incredibly busy on smoky days so response times may be impacted. 

Based on operational needs, employees can work with their supervisor to request alternate working arrangements. The Campus AQI Decision-Making Matrix (PDF file) describes actions based on outdoor conditions during wildfire smoke events. 

Laboratory Buildings

The HVAC systems serving laboratory spaces are different from those serving other types of spaces on campus.  The system serving a lab space supplies 100% outside air, meaning no air exhausted from a lab space is recirculated back into the system - it is all exhausted outside the building. 

indoor air quality lab diagram

Non-Laboratory Buildings

HVAC systems serving other types of spaces, such as office, classroom, and/or community spaces have different ventilation requirements than laboratory buildings. Systems serving non-laboratory spaces are designed to bring in at minimum the amount of outside air required for the design occupancy of the spaces (or the measured occupancy in the case of Demand Controlled Ventilation) and mix it with air returned from the spaces. Most systems are also designed to bring in more outside air (up to 100%) when outdoor conditions are favorable (i.e., not too hot or cold). This mixed air is then filtered at the central unit before it is supplied back to the space.

Indoor Air Quality Classroom diagram

Buildings without Mechanical Ventilation Filtration Systems

There are a number of ways to reduce smoke exposure in buildings or homes without ventilation & filtration:
  • Smoke can irritate the eyes and airways, causing cough, a dry scratchy throat, runny nose, trouble breathing, and irritated sinuses. Stay hydrated by drinking water during heavy smoke events.
  • Stay inside with the doors and windows closed.
  • At home, create a “clean room” with a portable HEPA air purifier properly sized for your space. 
  • Seek shelter elsewhere if you do not have an air conditioner and it is too warm to stay inside with the windows closed.
  • Do not add to indoor air pollution. Do not burn candles or use gas, propane, wood-burning stoves, fireplaces, or aerosol sprays. Do not fry or broil meat, smoke tobacco products, or vacuum. All of these can increase air pollution indoors.
  • Take it easier during smoky times to reduce how much smoke you inhale. If it looks or smells smoky outside, avoid strenuous activities such as mowing the lawn or going for a run.
  • Know your air quality. Stay tuned to local media for changes in smoke or weather conditions. Riverside information can be found at the EPA Air Nowwebsites.
  • Long-term smoke events usually have periods when the air is better. When air quality improves, even temporarily, air out your home to reduce indoor air pollution, and step outside yourself when you have a chance!
  • Outdoor workers and employees in campus buildings without mechanical ventilation filtration systems may pick up N95 respirators for voluntary use from EH&S when the air quality index is unhealthy outdoors (>150).  Request a N95 Respirator.