Several students, staffers and a parent were taken to hospitals Thursday after they were exposed to high levels of carbon monoxide gas that apparently leaked from a defective boiler at an elementary school in Northeast Washington, D.C. Fire and EMS officials said.

Langley Elementary School will be closed Friday because of the broken broiler and a forecast of near-freezing temperatures, D.C. schools officials said.

Medics evaluated 76 people, including 56 juveniles, outside the school in the 100 block of T Street NE about 3:30 p.m., said Tim Wilson, a fire department spokesman.

Four students, two staffers and a parent were taken to hospitals in serious, but not life-threatening, condition, Wilson said. Carbon monoxide is an odorless and colorless gas, and its effects can be toxic.

Authorities ventilated the elementary school and levels of the gas dropped, Wilson said.