Customs and Practices of the Moldmaking Industry has been the official guide for the classification of injection molds for thermoplastic materials since the early 1980s, when the Moldmakers Division of what was then the Society of the Plastics Industry issued the guide. The 21-page document, which describes best practices for procuring prototype and production tooling, was last revised in 1996. The trade group is now called the Plastics Industry Association (PLASTICS), and the document is currently undergoing review for updates.
The guide is aimed at avoiding misunderstandings and conflicts by all parties involved in the mold procurement process. While common practices are often followed, mold buyers may specify many unique requirements and preferences, and the guide is a starting point to safeguard from any potential disputes and differences of opinion.