A carbon dioxide leak at a Boulder, Colorado, swimming pool closed a recreation center for the day as staff worked to fix it.

On October 15, the Boulder Fire-Resue was dispatched to the North Boulder Recreation Center after reports of the smell of natural gas.

Crews immediately evacuated the building while they investigated the report. Rather than a natural gas incident, crews determined it was a HAZMAT issue, requiring the cooperation of the Boulder County Hazmat Team. A hazmat team entered the building, where they measured elevated levels of carbon dioxide. They found that the elevated levels of carbon dioxide were due to the pool’s carbon dioxide tank, which was emitting carbon dioxide either because it had been overfilled or had a bad valve. Carbon dioxide is used at the facility as part of balancing pH levels in the swimming pool to assist in disinfection.

No injuries were reported. The facility remained closed for the day while the building’s contractor made repairs.