A federal lawsuit has been filed by the Federal Trade Commission against Terralab Engineers Inc., alleging the West Jordan company conducted erroneous home-insulation tests.

The suit, filed in U.S. District Court in Salt Lake City, contends Terralab and its president, Douglas MacGregor, repeatedly violated regulations governing so-called "R-value" tests since June 1983.R-values are used to establish insulation materials' ability to retard heat transmission. A high R-value indicates a good insulator.

Claude Wild, regional director for the FTC in Denver, said Terralab tests had consistently produced R-values that were higher than the true R-values for the products.

Wild said the FTC filed the suit because "we were unable to reach a settlement with the company."

MacGregor refused to comment on the suit.

Terralab conducted R-value tests at temperatures other than the required 75 degrees, and the tests did not conform to the approved methods of the American Society of Testing and Materials, the FTC argues.

The agency also said the company performed tests on samples of polyurethane, polyisocyanurate and extruded polystyrene insulation materials that were not properly aged.

"The violations of the R-value rule have been many and widespread," the suit states. "Monetary penalties will not be adequate to deter the defendants from continued and future violations."

The suit said that each test can be considered a separate violation carrying a maximum $10,000 fine.

The FTC is seeking a court order to prevent Terralab from committing further violations and to force the company to pay all court costs.