Suggested Division 15 Specifications AeroBlade Steel Return Grilles Model Description 23RL Steel return grilles shall be TITUS AeroBlade Series Model 23R (¾-inch blade spacing) for the sizes and mounting types as shown on the plans and outlet schedule (add -NT for narrow tee). The fixed deflection blades shall be available parallel to the long dimension of the grille. Construction shall be of steel with a 1¼-inch wide border on all sides and a minimum border gauge of 20. Corners shall be assembled with full penetration resistance welds with a reinforcing patch for extra strength. Blades shall be accurately formed to a proven curvature that has been certified according to current industry standards in a certified laboratory. Blades shall have a minimum gauge of 20 with a fixed deflection angle of 45°. Optional opposed-blade volume damper shall be constructed of heavy gauge steel. Damper must be operable from the face of the grille. The grille finish shall be #26 white. The finish shall be an anodic acrylic paint, baked at 315°F for 30 minutes. The pencil hardness must be HB to H. The paint must pass a 100-hour ASTM B117 Corrosive Environments Salt Spray Test without creepage, blistering or deterioration of film. The paint must pass a 250-hour ASTM D870 Water Immersion Test. The paint must also pass the ASTM D2794 Reverse Impact Cracking Test with a 50-inch pound force applied. The manufacturer shall provide published performance data for the grille. The grille shall be tested in accordance with ANSI/ASHRAE Standard 70-1991. For Narrow Tee Models add: Grilles shall be compatible with 24 x 24-inch modules for regressed narrow tee ceiling systems.