ISO 20457 is the international standard governing tolerances and acceptance conditions for plastic molded parts. Within this standard, Tolerance Group 5 (TG5)
The allowable deviation in TG5 scales with the size of the part; larger parts naturally have wider absolute tolerances. Iso 20457 Tg5
Third, TG5 addresses . A perennial fear in recycling is the presence of legacy hazardous substances (e.g., brominated flame retardants in e-waste plastics). TG5 does not set health limits—that is the realm of chemical safety regulations—but it specifies detection and reporting standards . If a batch exceeds a defined threshold for a restricted substance, TG5’s protocol triggers a clear pathway: rejection, downcycling into a non-sensitive use, or decontamination. ISO 20457 is the international standard governing tolerances
Choosing TG4 requires tighter process controls and often higher-quality mold steel, which can significantly increase tooling costs . Part Dimensions: The allowable deviation in TG5 scales
Elara’s blood went cold. “Which test?”
TG5 is often the "sweet spot" for technical plastic parts that require a reliable fit without the extreme costs of ultra-high precision molding. Common Use Cases
But six weeks later, after a grueling round of revisions and a landmark experimental study from NIST proving Elara’s math correct, the revised clause passed.