You do not always need a new test report for every design, but a report only covers the materials and process that were tested. The usual approach is to test each combination of materials, retest whenever a material, supplier or process changes, and retest production lots at regular intervals.
For children's products sold in the US, the rules are more formal: an initial certification test, then periodic tests and retests after material changes.
When one report can cover several designs
If several designs use the same alloy, the same plating, the same solder and the same stones from the same suppliers, one set of component tests can support all of them. This is component testing, and US rules allow it for children's products under set conditions. It is also how most EU and UK buyers manage due diligence on large ranges.
The catch is that the components really must be the same. A maker who switches to a cheaper alloy for one design, or buys plating chemicals from a new supplier, has changed the product, even if it looks identical.
When to retest
- A new base metal, alloy, solder, coating or plating supplier.
- A change in the plating process or thickness.
- A new maker, even for an existing design.
- A failed test or a customer complaint.
- At set intervals for continuing production. For US children's products, periodic testing is required at least once a year, or less often where the rules allow a documented production testing plan.
Batch testing as a safety net
Even with design-level reports, many buyers test a sample from each production lot, or every few lots, especially with a new maker. Rajkot workshops often buy metal and findings in small quantities from changing sources, so material drift is a real risk. A quick XRF screen of each lot, plus a full lab test at intervals, is a common and affordable compromise.
Link every report to a lot number and keep the records. A report without a clear link to the goods shipped is weak evidence if a customs officer or retailer asks.
What this means for a buyer
Test by material set, write a ban on unapproved material changes into your purchase order, and retest whenever anything changes. Creston & Co works for buyers only, for a fixed fee agreed in writing. We track which materials each maker uses, draw samples from production lots and send them to accredited labs. Start with a free sourcing review.