Clark Elementary School

Clark students spend the day in poorly ventilated classrooms

Unless air purifiers are run consistently

Like nearly all PPS schools, Clark's HVAC system delivers low air-change rates in classrooms and other learning spaces. The district's own measurements show that Clark does not meet health-based goals for ventilation. The best way to reach healthy air targets is with a combination of building ventilation and effective in-room filtration, but ventilation in Clark is poor, and it is critical that Clark receives ongoing support for placing and using in-room air purifiers.

The one air purifier originally assigned to Clark‘s rooms is insufficient and undersized for Clark classrooms and large spaces. Two or more air purifiers per classroom can substantially improve air quality, reduce respiratory viruses and air pollutants, and achieve effective air cleaning, while running at quiet settings.

Two air purifiers are needed in Clark's classrooms, auditorium, kitchen, and teacher's lounge to more effectively clean the air. That’s why the Oregon Health Authority provided additional free air purifiers for Clark in 2023. Clark received enough additional units that each classroom should have two air purifiers each! But teachers and staff at Clark have also not gotten great guidance on how and why to use both air purifier. At other PPS schools where teachers didn't get sufficient guidance on using their air purifiers, we've been able to help the school community build better understanding and air quality practices, especially when parents at a school work with us. To connect and support next steps for clean classroom air at Clark, join our Clark group, and learn more about Clark‘s air quality below.

Without air purifiers, Clark does not have clean indoor air

One air purifier is undersized for Clark classrooms

With only one air purifier per classroom, Clark classrooms still lack clean air:

Although the Intellipure air purifiers originally assigned to Clark improve the school's clean airflow rates, they are insufficient in Clark classrooms. Even with an Intellipure air purifier running at its reasonable noise level (half speed), the classroom with the lowest ventilation from the HVAC system — room 15 — is still far below healthy airflow targets. With room 15 at 2.8 air changes per hour, kids’ and staff’s viruses in their respiratory aerosols linger for over 49 minutes.

At 2.8 air changes/hour, 49 minutes is how long it takes for the HVAC system and Intellipure air purifier to clear out 90% of the respiratory aerosols being produced when kids and staff breathe, talk, sing, cough and sneeze.

With only one air purifier per classroom:

✘ Worst-airflow classroom (room 15) is still less than 3 air changes per hour

✘ 1 other Clark classroom has less than 3 air changes per hour

✘ 19 classrooms are between 3 and 6 air changes – below recommendations

If one Intellipure unit is running at its quiet noise level, only 1 classroom meets our minimum goal for healthy ventilation and filtration of 6 air changes per hour or more, clearing 90% of aerosols out in 23 minutes or less.

Rm 11: 6.3***

***Good airflow: Just 22 minutes to clear 90% of aerosols in room Rm 11

This classroom has good airflow, but it could be even better. At 12 air changes an hour, aerosols clear out by 90% in under 12 minutes.

Clark needs two air purifiers per classroom to clean classroom air

Two air purifiers make a big difference — but some rooms still fall short

In some Clark classrooms, the baseline ventilation is so low that two air purifiers alone cannot fully solve the problem. Even so, using both an Intellipure and a Medify Pro still makes a major difference in these rooms, reducing exposure for students and staff compared with using only one unit, or none.

For example, Clark‘s worst-airflow classroom — Room 15 — is 5.1 air changes per hour even with two air purifiers. Although this is still below the minimum healthy air target of 6, it is far better than the 1.7 air changes per hour the room gets with no air purifiers running. Room 14 follows the same overall pattern: it reaches only 5.3 air changes per hour with two air purifiers, meaning that viruses, bacteria, asthma triggers, and other air pollutants linger in the classroom air for over 26 minutes. But without both air purifiers, Room 14 is only 1.9 air changes per hour. Room 7 is a third example with the same story. Even when operating two units, Room 7 is only 5.4 air changes per hour, but that airflow level is an important health protective improvement over the 2.8 air changes the room gets if relying on the HVAC system alone.

Visualizing how much air purifiers improve Clark classroom airflow

The graphs below show how little ventilation most Clark classrooms get without any air purifiers running. They also show how the addition of one air purifier per classroom shifts the rooms’ airflow rates higher but still leaves most rooms below health-based benchmarks for clean air. With two air purifiers per classroom, the pattern changes. Although two air purifiers still leave most classrooms short of 6 air changes per hour, having two units per room moves 9 classrooms into the healthy air range above 6, and the lowest airflow classrooms are much improved.

Number of classrooms vs air changes per hour

Next steps: support and strengthen Clark's clean air practices and daily use of two air purifiers

Clark received enough additional air purifiers that every classroom should have two units. The next step is ensuring Clark teachers and staff are supported in using their units and understand how and why they want to run multiple air purifiers. Many schools have not been given clear information about how multiple air purifiers running quietly together are needed to clean the air in a full classroom of 20 or 30 kids. And teachers have not been given good guidance on how and when to use both units. But these second units need to be in classrooms and other school spaces providing critical benefits of clean indoor air, such as reduced illness, improved learning, and better attendance.

Placing and using this clean air infrastructure needs action at all levels, from district leadership to the classroom. Parents, caregivers, and school staff also have key roles to play to support daily use of two air purifiers in Clark classrooms and ensure clean classroom air. Join SIAFOS and our Clark group to connect with others who care about clean, cool classroom air at Clark.

How can you help with clean air for Clark?

Let’s support Clark in using clean air tools well — Sign up to help ensure air purifiers are in place and running quietly to keep Clark classroom air clean!

Two air purifiers running at quiet settings in each classroom would provide more air filtration to the 15 Clark classrooms that do not even get 3 changes of air per hour and the 7 classrooms that only get between 3 and 6! Using multiple air purifiers would also ensure Clark‘s cafeteria, where kids pack in close to eat lunch, and library and other key spaces get better air quality, too.

Join us to be part of a group of parents and community members advocating for strategic, effective, and science-based planning for sufficient ventilation and filtration capacity in PPS schools — including Clark. PPS air quality efforts have cycled between strong progress as well as periods of inaction and missteps. We are now working more collaboratively with district leadership, yet long-standing gaps in ventilation and air filtration persist across the district — which is why parent, staff, and community involvement at the classroom level, school level, and district level remains so important.

Changing our schools in PPS to have good air quality practices only happens when families and staff work together. When you join us, we’ll connect you with others and share simple processes that help PPS kids and staff, including kids and staff at Clark, learn and work in classrooms with cleaner air, less illness, and healthier learning environments. Sign up below to join our organizing for PPS air quality!

*Notes on our numbers

Air changes per hour given on this page are “equivalent” and include ventilation and filtration.  These numbers are based on the district’s airflow report for Clark, conducted in August 2021 (available at safeairoregon.org/original-airflow-reports) but corrected gaps and errors.