Miles-Platts Precision technical mouldings and tool making

Miles-Platts Precision technical mouldings and tool making


Layout of the Yellow Card

Layout of the yellow card

Approval of Engineering Plastics

UL approval is generally essential before equipment can be sold in the United States. Approval tests on equipment are lengthy and expensive. The operation can however be greatly simplified if UL-approved materials, i.e. appearing on the yellow cards, are used. Engineering plastics manufacturers are therefore having an increasing number of materials approved, to make things easier for users.

Man using computer

Approvals covers three aspects:

  • flame class, governed by the UL 94 standard,
  • temperature indices, governed by the UL 746 B standard,
  • basic properties, determined under the UL 746 A standard.

The results are given for each material, in each colour, and for a specific thickness, which is the actual thickness of the specimen tested. This means that comparisons between materials are valid only if the thickness is the same.

Updated On: 01/08/2015