Above are the results of additional firmness testing of the two sample cores. The sample cores were subjected to ASTM F 1566-09 Firmness testing in the previously tested section and compared to sections that have not been subjected to any physical testing. The samples consisted of the Queen unit’s innerspring core, the Full units core with the 2” piece of foam that was adhered to the core and of the core with the 2” cushion removed (core only).
The firmness testing shows the innerspring core to have 4..9% softening between the untested and tested areas which could be attributed to the relaxation of the pocket material which is normal after a 100,000 cycle durability test. The foam core with the 2” foam cushion attached showed 32.9% softening between the untested and tested area. The core alone showed 20.3% softening between the untested and tested area.
These results would indicate that the innerspring after a full durability test retains essentially all its firmness characteristics and that the cushioning material used to complete the mattress assembly is where the majority of the change of firmness does occur. The results also indicate the foam core of the full size sample contributed significantly to the amount of change in the mattress sample.
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Leggett & Platt, Incorporated
Manager, International Technical Center