ALEXANDRIA, Va., June 12 -- United States Patent no. 12,295,813, issued on May 13, was assigned to 3M Innovative Properties Co. (St. Paul, Minn.).
"Dual hearing protection system" was invented by Paul D. Henry (Carmel, Ind.), David L. Albean (Indianapolis), Oscar L. Karekull (Huskvarna, Sweden), Cameron J. Fackler (Indianapolis), Andreas T. Andersson (Nissafors, Sweden) and Abel Gladstone Mangam (Varnamo, Sweden).
According to the abstract* released by the U.S. Patent & Trademark Office: "A hearing protection system is provided. The hearing protection system has a first active hearing protection system. The first active hearing protection system is level-dependent. The hearing protection system also has a second active hearing protection ...