DANVERS, Mass. -- The CAI chemical plant that exploded in Danvers last week went uninspected by state and federal authorities because it was considered too small to be a priority, according to a new report.

NewsCenter 5's Gail Huff reported that state inspectors usually focus their attention on larger companies.

Emergency 911 calls indicated that few Danversport residents who called police after the explosion seemed to know they lived near a chemical plant, or that there could be an explosion in their neighborhood. Many thought a plane had crashed or a bomb had gone off.

Environmental regulators never inspected the plant, according to information obtained by the Boston Globe. Only 2 percent of companies like CAI are inspected by the state's Department of Environmental Protection, in comparison to the 20 percent of larger companies that are inspected each year. The federal government requires states to inspect plants that produce large amounts of hazardous waste -- at least five 55-gallon drums a month, according to the Globe report.

The state fire marshal, however, never inspected the Danvers plant in its 11-year-history, although they will if called in by a local fire department. The Danvers Fire Department never requested an inspection, although it did check the plant in 2002 and found no violations. The federal Environmental Protection Agency did not inspect it either.

As fire crews responded to the scene, however, they knew they had the potential for a large disaster.

"We have a large propane tank here still in the process of venting. Give me as many ambulances as you can down here. We have multiple injuries," a firefighter said on 911 tapes released Tuesday.

The CAI company was up to date in its compliance with environmental reporting laws.