The state Department of Education on Tuesday identified seven Oahu schools housing 73 classrooms with the highest levels of carbon dioxide — a sign of poor ventilation, which is a risk factor for the spread of COVID-19 — and said steps to improve conditions already have begun.

However, the Hawaii State Teachers Association and other critics are demanding more detailed information and questioning why fixing the affected classrooms has taken 11 months and counting since a contractor began last fall to collect CO2 data from schools.

The campuses with the 73 classrooms with the highest levels of carbon dioxide are Kauluwela, Keone‘ula, Pu‘u­hale and Royal elementary schools; Mililani Middle School; and McKinley and Mililani high schools. The numbers of classrooms at each school ranged from 24 at Kauluwela and 19 at Keone‘ula, down to one classroom at Mililani High.

“Definitely, we prioritize the health and safety of our students, first and foremost,” state schools Superintendent Keith Hayashi said Tuesday afternoon during a media availability. “We will continue to monitor those classrooms. We will get them on our website so they (parents) know which classes are being addressed. We want to be sure to convey to the parents we are doing all we can, that we will ensure those classrooms meet the necessary (safety) criteria.”

Additional box fans and air purifiers are being added to those classrooms, and other improvements are being made as needed, and they will continue to be monitored, said Randall M. Tanaka, assistant superintendent for the DOE Office of Facilities and Operations.

On Tuesday night the department published on its website a list of the 73 classrooms, with a general description, square footage and where the classroom falls in the DOE’s five-tier priority system, but it did not include classroom numbers. DOE Communications Director Nanea Kalani said specific classroom numbers will be given directly by schools to their communities. “Parent letters are going out this week to families at the seven impacted schools,” she said.

The teachers union says the DOE’s steps so far are helpful but not enough. “Honestly, we just want them to be transparent. We want them to be clear about what they have found and what they have done,” said Andrea Eshelman, HSTA deputy executive director. She added that the union wants to know why improvements to classrooms in need have taken so long, whether all 12,000 of the state’s public school classrooms have been assessed for air quality, and how results will be made accessible.

The issue of classroom air safety has taken on new urgency because as about 160,000 public school students and more than 42,600 full- and part-time school employees return to campuses this week, masking is no longer required, although it is strongly encouraged by state education and health officials. The CDC recommends indoor masking in places where community levels of COVID-19 are high, which at last check included Honolulu, Maui and Hawaii counties.

Hayashi and Tanaka spoke with members of the media Tuesday after a July 26 letter from Tanaka to the HSTA outlining the results of classroom ventilation assessments and other steps by the DOE to improve classroom air quality was made public. The union says Tanaka’s letter marked the first time the DOE had responded with significant details to a formal request for information that the teachers union made almost a year ago, in September.

Of the 12,000 classrooms in public schools statewide, approximately 10%, or 1,261 classrooms, have limited access to outside air due to central air conditioning. The other classrooms have access to outside air with windows and doors, and thus can increase airflow into the classroom, according to the DOE.

Tanaka’s letter described a study initiated in September that in part assessed carbon dioxide levels in classrooms identified as potentially having limited ventilation. In the letter, Tanaka described the classroom carbon dioxide assessments among the department’s “steps to improve air quality to reduce the risk of airborne spread of COVID-19.”

A total of 335 classrooms were equipped with carbon dioxide sensors that tracked levels for 12 hours a day on weekdays, excluding holidays and school breaks. The data collected “informed” the estimated carbon dioxide levels for 904 other classrooms with similar room configurations and air-conditioning supply, according to the DOE. The average of the highest 5% of each classroom’s carbon dioxide readings, measured in parts per million, was used to place classrooms into five tiers. The tiers set the DOE’s priority for actions to increase ventilation:

Tier 1 (less than 800 ppm): 337 classrooms

Tier 2 (800 to 1,100 ppm): 525 classrooms

Tier 3 (1,100 to 1,500 ppm): 304 classrooms

Tier 4 (1,500 to 2,000 ppm): 70 classrooms

Tier 5 (more than 2,000 ppm): 3 classrooms

The 73 rooms ranked in tiers 4 and 5 include 67 classrooms, and six other rooms, including office and storage space, a workroom and a resource room, according to the DOE. “The Office of Facilities and Operations will follow up on the classrooms identified in tiers 3, 4 and 5 to ensure steps are being taken to improve air quality to the extent possible,” Tanaka said in the letter. In the media availability, Tanaka added that testing and data analysis are an ongoing process.

The 73 classrooms in tiers 4 and 5 are getting immediate priority for now, Tanaka said. Kalani later added that classrooms in Tier 3 will be addressed in coming weeks.

Twenty-two more classrooms that have limited access to outside air were left out of the tiers. Kalani said 10 classrooms had room numbers that didn’t match the DOE’s database, and 12 were manually assessed, so they have not been placed in the tiers.

The department maintains that it has made major strides to improve classroom air quality. Its latest “COVID-19 Health and Safety Guidance” document includes an updated section on ventilation, Kalani said. In addition, 12,000 20-inch box fans, for every classroom, and more than 4,000 HEPA air cleaners, for use especially in classrooms that lack doors or windows that open to the outside, have been purchased and distributed by the department.

Schools also were given supplies to build their own Corsi-Rosenthal air cleaners, using MERV-13 filters and box fans; 600 carbon dioxide sensors were purchased and distributed so schools could monitor their own levels; and central air conditioners are “maintained regularly to ensure optimal airflow,” Tanaka said.

POOR VENTILATION

The 73 rooms ranked in tiers 4 and 5 include 67 classrooms and six other rooms, including office and storage space, a workroom and a resource room. They are at the following seven schools on Oahu:

>> Kauluwela Elementary, 24 classrooms

>> Keone‘ula Elementary, 19 classrooms

>> McKinley High, 10 classrooms, 6 rooms

>> Pu‘uhale Elementary, 8 classrooms in library

>> Royal Elementary, 3 classrooms

>> Mililani High, 1 classroom

>> Mililani Middle, 2 classrooms

Source: State Department of Education