Traditionally, cellular foam products have been checked for load deflection by determining the load required to cause a 25% deflection. In automotive seating, on the other hand, the load deflection is checked by determining the thickness under constant force conditions to (a) indicate the initial softness of the seat cushion, (b) measure how thick the seat cushion is under the average passenger load (a measurement of padding left for “ride” and seated height), and (c) determine a value to indicate resiliency. In this method these measurements are made by determining the thickness of the seat cushion under fixed loads of 4.5 N, 110 N, and 220 N with a 323 cm2 circular indentor foot.
SAE J815-2007 history
2012SAE J815-2012 Load Deflection Testing of Urethane Foams for Automotive Seating
2007SAE J815-2007 Load Deflection Testing of Urethane Foams for Automotive Seating
2002SAE J815-2002 Load Deflection Testing of Urethane Foams for Automotive Seating
2001SAE J815-2001 Load Deflection Testing of Urethane Foams for Automotive Seating
1998SAE J815-1998 Load Deflection Testing of Urethane Foams for Automotive Seating
1994SAE J815-1994 LOAD DEFLECTION TESTING OF URETHANE FOAMS FOR AUTOMOTIVE SEATING
1962SAE J815-1962 Load Deflection Testing of Urethane Foams for Automotive Seating