Waltham, MA - Waltham fire responded to a fire alarm activation at the Waltham High school on December 30. Engine 2, 7 and Tower 1 arrived and found numerous people outside the building. A medic unit was then requested. It was determined there were high carbon monoxide readings of 200 ppm in several areas in the school. After about an hour and half, firefighters had cleared the building of carbon monoxide and determined that there was an issue with one of the boilers. Although the school was closed for vacation, there were some administrators and the high school basketball team who were practicing in the school. None required medical assitance.