Section 1633.6 - Quality assurance requirements(a)Quality assurance. Each manufacturer shall implement a quality assurance program to ensure that mattress sets manufactured for sale are the same as the qualified and/or confirmed prototype on which they are based with respect to materials, components, design and methods of assembly, except as permitted by § 1633.4(b) . At a minimum these procedures shall include: (1) Controls, including incoming inspection procedures, of all mattress set materials, components and methods of assembly to ensure that they are the same as those used in the prototype on which they are based;(2) Designation of a production lot that is represented by the prototype; and(3) Inspection of mattress sets produced for sale sufficient to demonstrate that they are the same as the prototype on which they are based with respect to materials, components, design and methods of assembly.(b)Production testing. Manufacturers are encouraged to conduct, as part of the quality assurance program, random testing of mattress sets being produced for sale according to the requirements of §§ 1633.3 and 1633.7 .(c)Failure of mattress sets produced for sale to meet flammability standard - (1)Sale of mattress sets. If any test performed for quality assurance yields results which indicate that any mattress set of a production lot does not meet the criteria of § 1633.3(b) , or if a manufacturer obtains test results or other evidence that a component or material or construction/assembly process used could negatively affect the test performance of the mattress set as set forth in § 1633.3(b) , the manufacturer shall cease production and distribution in commerce of such mattress sets until corrective action is taken.(2)Corrective action. A manufacturer must take corrective action when any mattress set manufactured or imported for sale fails to meet the flammability test criteria set forth in § 1633.3(b) .