A 911 call came in from the Control Associates on Commerce Drive just off southbound Route 17 at 12:50 p.m., Allendale Police Chief Michael T. Dillon said.
The caller "reported that a few employees had felt ill," the chief said.
Allendale police, firefighters and EMS were among the responders.
They were told that the odor was first detected on Wednesday, Dillon said.
EMS evaluated the four employees, who didn't require further attention.
Firefighters conducted an extensive search, deemed the situation under control and turned the building back over to management, who the chief said "will continue to monitor possible causes of the odor."
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