How to Choose a Testing Laboratory
Choosing a laboratory is less about finding the biggest name and more about matching your specific test, material and industry requirement to a laboratory whose documented scope covers it.
Start with the test, not the laboratory
Write down the standard or method you need (if you know it), the material or product, and the decision the result supports. A laboratory that is excellent at polymer tensile testing may have no capability in EMC or microbiology.
Check capability before accreditation
- Does the laboratory list your specific method or standard in its published scope or capability list?
- Does it work with your material or product type routinely?
- Can it handle your sample size, quantity and condition?
Then check accreditation — against the scope
ISO/IEC 17025 accreditation applies to specific methods listed in the laboratory's scope of accreditation, not to the laboratory as a whole. Ask for the scope and confirm your method is on it.
Practical factors that decide between shortlisted laboratories
- Realistic turnaround for your timeline, stated for your method
- Whether they ask good questions about your sample and requirement
- Reporting format and whether it meets your customer's or regulator's expectations
- Experience in your industry and with your end use
Common questions
- Should I always choose an accredited laboratory?
- Where a customer, regulator or specification requires accredited results, yes — and the specific method must be on the accreditation scope. For exploratory or internal work, a capable non-accredited laboratory may be appropriate.
- Is the cheapest quotation the best choice?
- Not usually. Compare what is included: number of specimens, report detail, retest policy and turnaround. A slightly higher quote with a complete scope is often cheaper than a low quote with extras.