AIR QUALITY

Boston Public Schools implements a “layered risk reduction approach” to Indoor Air Quality (IAQ) Management, as recommended by the U.S. Environmental Protection Agency (EPA) and U.S. Department of Education. This approach includes following available public health and ventilation technical guidance from national, state, and local experts such as the Centers for Disease Control and Prevention (CDC) and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Learn more here about the BPS layered risk reduction approach to managing IAQ and improving a healthy school environment.

BPS school buildings fall into one of three categories: buildings with central HVAC, buildings with steam heat and limited mechanical ventilation, and buildings with steam heat and no mechanical ventilation. The buildings with steam heat and limited mechanical ventilation, and the buildings with steam heat and no mechanical ventilation rely on operable windows as their primary source of ventilation.

Additional details on each school are below.

Ventilation / Air Purifiers / Air Filters

Beginning in 2020, BPS implemented the following strategies to improve indoor air quality and thermal comfort within school buildings, and assist with reducing the risk of disease transmission:

• Inspected 27,000 windows and completed necessary repairs on 12,000 windows.
• Distributed more than 6,400 fans for exhausting air out of classrooms.
• Distributed Medify-40 HEPA air purifiers to all classrooms, and Delos compact air purifiers to offices where necessary. Air purifier filters are changed every six months.
  • Air purifier guidance.
  • Air purifier set-up.
• For the schools with HVAC systems, BPS upgraded more than 4,300 filters to MERV-13 filters, where allowable by the equipment. All HVAC filters are replaced in accordance with regular, ongoing building system maintenance.
• Conducted 750+ air exchange/ACH tests across all schools, helping us make adjustments to increasing fresh air intakes in mechanical ventilation systems, and demonstrating the excellent air changes per hour provided by operable windows.
• Raised classroom temperature set-points to offset the need for open windows and improve thermal comfort.
• Ran exhaust fans 24 hours/day, seven days/week.
• Implemented 2 hour pre- and post-occupancy flushing of buildings. The new ASHRAE 241 standard recommends only post-occupancy flushing.
• Installed indoor air quality sensors in all classrooms, Main Offices, and Nurse’s Offices in all school buildings, sharing the data live through an online, public dashboard. Learn more here.
• Installed ~4100 window air conditioning units in classrooms as of Sept. 2023; we estimate that every school will have cooling, where allowable, by December 2023.
• We have implemented full HVAC systems in our new school builds, and continue to explore funding, permits, and plans for implementing more ventilation systems across the district.

Buildings with Central HVAC

What It Is and How It Works

There are 38 school buildings in the district with all-inclusive heating, ventilation, and air conditioning (HVAC) systems. These systems maintain air quality, control temperatures, and regulate humidity by pulling fresh, filtered air into the building and blowing indoor air outside. Buildings in this category typically have limited operational windows. 

All central HVAC systems are operated and monitored remotely using an Automatic Temperature Controls (ATC) system, which allows the BPS Planning & Engineering team to see whether the equipment is operating properly and to make adjustments when needed. 

Preventative Maintenance & Repairs 

The Planning & Engineering team manages all preventative maintenance and repairs to HVAC systems using highly qualified mechanics and technicians. Central HVAC systems are inspected, serviced, and repaired on a seasonal schedule. For example, preparation for air conditioning operations begins in January and includes service to all HVAC equipment. Air filter changes are scheduled based on recommendations from the equipment manufacturers and industry best practices, but scheduled replacements are adjusted when needed.

Buildings with Steam Heat

What It Is and How It Works 

There are 27 buildings in the district with steam heat and no mechanical ventilation. Instead of mechanical ventilation systems that circulate air using ducts and fans, these buildings use windows as the primary source of airflow. Heat is provided by steam-heating boilers and radiators. These buildings do have exhaust fans in all bathrooms, which continuously blow indoor air outside of the building. 

All steam heat systems are controlled and monitored remotely using an Automatic Temperature Controls (ATC) system, which allows the BPS Planning & Engineering team to see whether the equipment is operating properly and to make adjustments when needed. 

Preventative Maintenance & Repairs 

The Planning & Engineering team manages all preventative maintenance and repairs to heating systems using highly qualified mechanics and technicians. Steam heat systems are inspected, serviced, and repaired on a seasonal schedule. For example, preparation for heating operations begins in July of each year and includes service to all boiler and radiator equipment. Boilers are also inspected annually by the MA Department of Public Safety. 

Buildings with Steam Heat and Limited Ventilation 

What It Is and How It Works 

Mechanical ventilation systems circulate fresh air using ducts and fans rather than relying on natural airflow through open windows or doors. There are 68 school buildings in the district with steam heat and limited mechanical ventilation. These buildings use steam-heating boilers and radiators as their heating source. Windows are the primary source of ventilation, but they also have some mechanical ventilation such as exhaust fans, which continuously blow indoor air to the outdoors, and unit ventilators that filter and control the temperature of outdoor air blown into a classroom.

All steam heat and limited ventilation systems are scheduled, operated, and monitored remotely using an Automatic Temperature Controls (ATC) system, which allows the BPS Planning & Engineering team to see whether the equipment is operating properly and to make adjustments when needed. 

Preventative Maintenance & Repairs

The Planning & Engineering team manages all preventative maintenance and repairs to heating and ventilation systems using highly qualified mechanics and technicians. These systems are inspected, serviced, and repaired on a seasonal schedule. For example, preparation for heating operations begins in June and includes service to all boiler and radiator equipment. Boilers are also inspected annually by the MA Department of Public Safety. Air filter changes are scheduled based on recommendations from the equipment manufacturers and industry best practices, but scheduled replacements are adjusted when needed.