(Portland, OR) -- A group of nearly 40 nurses in the Portland Public School District are voicing concerns regarding COVID-19 protocols in the classrooms. The nurses issued a letter to district administrators yesterday. They say out-of-date tests are being used, students need to be provided with KN-95 masks, and many schools need better air filtration. They are also concerned contact tracing isn't as effective as it could be. The school district has said the precautions being taken will reduce the risk that the virus will spread.