5. Procedure5.1 Tape a segment of p

5. Procedure5.1 Tape a segment of plastic sheet, approximately 18 by 18in. (457 by 457 mm), tightly to the concrete surface makingsure that all edges are sealed.5.2 Allow the plastic sheet to remain in place a minimum of16 h.5.3 After the allowed time has elapsed, remove the plasticsheet and visually inspect the underside of the sheet and theconcrete surface of the patch for the presence of moisture.5.4 Sampling:5.4.1 Floors—One test area per 500 ft 2 (46 m 2 ) or portionthereof, of surface areas unless otherwise specified.5.4.2 Walls and Ceilings—One test area per 500 ft 2 (46 m 2 )or portion thereof, of surface area unless otherwise specified.5.4.3 The recommended practice is a minimum of one testfor each 10 ft (3 m) of vertical rise in all elevation startingwithin 12 in. (300 mm) of the floor.