The Wallingford Fire Department, police and the Federal Bureau of Investigation investigated at 89 North Plains Industrial Road after white powder was found strewn in various places on Friday morning.
The owner of the remodeling and restoration company found the powder sprinkled in several places in front of a garage when he arrived to work around 6 a.m., according to authorities.
Preliminary tests indicate that the substance is not harmful, fire officials said, and the owner of the industrial park plans to hire a contractor to clean up the mess.
The FBI will conduct further tests on the substance the police are trying to determine whether a crime was committed or if this was an accident.
"It's quite possible it's an accident. We don't know at this point how it got there and why it's there, but that's part of the investigation," Lt. Marc Mikulski, of Wallingford Police, said.
Police said the business owner rents a garage. The company name was not immediately available.