The checklist we give customers doing their own audits:
1. Incoming component inspection area — are they actually testing LED reels and driver batches when they arrive, or just trusting the supplier's label? Look for an integrating sphere (for LED testing) and a programmable electronic load (for driver testing). If these aren't present, quality control starts at final assembly, not at components — that's late.
2. Production line organization — is there an ESD (electrostatic discharge) management system? Wrist straps, grounded mats, humidity control? LEDs die silently from ESD damage that doesn't show up for months.
3. In-line testing stations — there should be at least a power-on + wattage test at the end of the assembly line, not just a visual check. A proper line tests every unit, not just a sample.
4. Aging/burn-in room — finished products should spend at least 4–8 hours powered on at elevated temperature before packing. This catches infant-mortality failures before they reach your customer.
5. Third-party lab relationships — ask which accredited labs they use for LM-79, LVD, and EMC testing. If they can't name one, they're doing everything in-house or not testing at all.
6. Export documentation capability — can they produce a certificate of origin, a commercial invoice that matches L/C terms, and the CE Technical File without days of back-and-forth? The administrative competence of the export department is a proxy for the general competence of the company.
If an audit isn't practical, hire SGS, Bureau Veritas, or Intertek to do it — they have local offices in every major Chinese manufacturing city and charge a few hundred dollars for a half-day factory audit.