Validity factors
Sampler qualification
- Certified Industrial Hygienist (CIH) or equivalent
- Insured professional with documented methodology
- Florida business license
Sampling pump calibration
- Annual calibration required
- Documented flow rate verification
- Temperature/humidity recording during sample
Sample chain of custody
- Documented transfer to lab
- Timestamps, signatures
- Sample integrity preservation
Lab accreditation
- AIHA-LAP accreditation preferred
- AAFRB or equivalent for specific tests
- Documented QA/QC protocols
Interpretation qualifications
- Written analysis by qualified professional
- Reference to industry standards (IICRC S520, AIHA)
- Outdoor baseline comparison
Common validity challenges
"Do-it-yourself" kits
- Uncontrolled sampling conditions
- Lab uncertainty
- Typically discounted or rejected
Contractor "testing"
- Remediator has conflict of interest
- Interpretation biased
- Carrier challenges immediately
Sample-of-one
- Single air sample doesn't meet protocol
- Need comparison samples
- Need sampling distribution
Old samples
- Conditions change; samples have limited shelf-life
- Re-sample if claim runs long
What holds up
- Third-party CIH sampling
- Accredited lab analysis
- Multiple samples (indoor affected, indoor control, outdoor)
- Written interpretation per IICRC S520
- Coordination with claim timeline