UPDATE: Cause of Hazmat Scare Remains Unknown

Editor's Note: This story was revised at 12:50 p.m. on Thursday to include new information from HealthPoint.

Healthpoint's Redmond clinic is set to reopen Friday morning after additional tests by an industrial hygienist failed to detect anything abnormal, clinic spokeswoman Diana Olsen said Thursday.

“They’re not finding anything," she said. "We’ve declared it safe for everybody to go back in.”

Olsen said the industrial hygienist also collected samples that will be tested in a lab as an extra precaution.

Thirteen staff members from the clinic were treated and released at Evergreen Medical Center in Redmond after they reported feeling nauseous and dizzy Wednesday morning.

Crews from the responded to the scene at the HealthPoint clinic on Northeast 87th Street at about 9:30 a.m., said department spokesman Jim Bove. Initial air tests did not show anything abnormal, and the Eastside Hazardous Materials Team was called in to perform its own tests, which also did not detect anything amiss.

An FBI Haz-Mat team was called to the scene as a precautionary measure, Bove said, and crews from the Woodinville and Bellevue fire departments were also on the scene.

"At this point ... there are really no red flags going up on our end," Bove said.

Northeast 87th Street was closed between 161st and 164th avenues northeast for several hours and reopened at about 2:30 p.m.

Debbie Wilkinson, chief operations officer for HealthPoint, said employees in the health center noticed something was amiss when they detected an odor toward the back of the building.

"Staff started feeling light-headed and nauseous," she said, adding that the workers have no idea what caused them to feel sick.

"It's an unknown at this point," Wilkinson said.

Bove said a total of 20 staff members and four or five patients were evacuated from the clinic. Three other nonprofit offices that are located in the same building, including Habitat for Humanity of East King County, were also evacuated.

Employees were allowed to re-enter the building at around 2:30 p.m.