B2B buyers must ensure frames meet international safety standards to avoid legal liabilities. For the EU market, compliance with ISO 4210 (Safety requirements for bicycles) is mandatory. For the US, ensure adherence to CPSC 16 CFR Part 1512. Key technical checks include head tube alignment, bottom bracket threading (BSA vs. Press-fit), and dropout spacing (e.g., 142x12mm thru-axle for modern discs). Request fatigue test reports (horizontal and vertical force tests) from the supplier to guarantee the frame can withstand at least 100,000 cycles without cracking.