VANCOUVER -- A dozen local presidents from the B.C. Teachers' Federation have released a statement calling for safety improvements at schools in the Fraser Health region.

Some of the requested safety measures are the same ones the union has been championing for months: a policy of mandatory masks in all indoor school settings, and a reduction in class sizes that would make physical distancing possible in every classroom.

The 12 presidents also asked that educators and school staff be "appropriately prioritized to receive vaccinations as soon as possible."

"Across the Fraser Health region, mask use is inconsistent, cohorts easily break down, and there is little room for physical distancing, especially in schools that are full or over capacity," they wrote in a public statement.

"More needs to be done to improve preventative measures. Many schools in the Fraser Health region are not safe enough and the status quo is unacceptable."

The union presidents also asked health officials for a clearer explanation of the threshold for declaring a COVID-19 outbreak in a school, as opposed to an exposure event. They referenced an incident at one unnamed school in Burnaby where a "number of staff and students in the same week contracted COVID-19," but an outbreak was never declared.

"It’s time to make changes, improve transparency, and take decisive action to improve the safety of our schools," they wrote.

Fraser Health has been a focus of much attention in recent months amid high coronavirus case numbers. Nearly two-thirds of the 761 new infections announced by B.C. health officials Thursday were in the Fraser Health region, which spans from Burnaby to Boston Barr.

There have already been COVID-19 exposure events at seven schools in the region since students and teachers returned to the classrooms on Monday, though there's no indication that anyone became sick as a result.

Provincial health officer Dr. Bonnie Henry has stressed that despite hundreds of exposure events in the first semester of the school year, there was very little actual COVID-19 transmission.

At a modelling presentation she gave days before Christmas, Henry said fewer than 0.7 per cent of B.C. students have been confirmed to have COVID-19.