The Costco store in Waipio and surrounding businesses reopened following the release of refrigeration gas at the popular warehouse store Friday that forced an evacuation of the area.

Costco was reopened about 4 p.m. after fire officials determined that oxygen levels were safe, fire Capt. Terry Seelig said. Firefighters used fans to help push the gas out of the building.

Officials determined that the source of the leak, first reported shortly after 2 p.m., was a rupture in the line that feeds R22 refrigerant gas. That break caused about 400 pounds of the gas to release into the Costco building, Seelig said. 

While the type of gas released is not considered toxic or flammable, it can be an irritant to human skin, he said.

Four Costco employees complained of dizziness, but no one required medical attention, he said.

About 400 customers and 50 employees were in the building when it was evacuated, Seelig said.

An additional 150 workers and customers in neighboring businesses were also evacuated for a time, he said.