Material Certification Types
APP uses the following terminology to address certification of raw materials.
Certificate of Conformance (CofC):
A document supplied by the material manufacturer that specifies that the materials supplied meet the requirements specified (typically the manufacturer's own stated properties). A CofC is typically not signed nor does it reference purchase order numbers (only lot numbers). The value of a CofC is limited to traceability.
Certificate of Analysis (CofA):
A document that states that the materials supplied meet the required specifications and has actual test results and methods. It is signed by the testing agency and typically ties to both the lot numbers involved and the purchase order. A CofA almost always has an additional cost and time requirements.
By default APP supplies a CofC which for most plastic molding materials only covers the manufacturer's published specifications. If a certification to a specification is required (ASTM, MIL, FED, MIS, Boeing, etc.) independent testing is often required. Testing to meet all the requirements of some standards is quite expensive and many times there are no materials available that meet all the requirements. There are exceptions; for instance, many thermosetting materials can be purchased to meet ASTMD standards with only small fees for a CofA.
One solution is to find a suitable material for the specification, have it tested to make sure it meets the requirements, and for future orders accept the material on a CofC. Testing could be required on a periodic basis.
Another solution is to only test some key characteristics of a selected material.
In all situations APP will help you find the most cost effective solution that meets the requirements for your plastic molding program.