Hacker Industries, Inc. announced an increase from 66 to 82 Underwriters Laboratories listings for its line of floor underlayments sold under the brand names of FIRM-FILL Gypsum Concretes and GYP-SPAN Radiant. These 82 UL listings detail floor ceiling assemblies utilizing a Hacker Floor Underlayment as an integral component to achieve a 1-, 2-, 3- or 4-hour fire rating.