Which method is appropriate for OSHA personal samples according to the source material?

• A. OSHA Reference Method
• B. NIOSH Method 7400
• C. EPA Method 9
• D. ISO 17025

Answer: (A)

OSHA personal sampling relies on a defined reference method because it provides the standardized procedure OSHA recognizes for regulatorily valid measurements. The reference method specifies how to collect the sample (sampling device, media, pump flow, and duration), how to preserve and ship the sample, and how the contaminant is quantified. Using this method ensures the results are defensible and directly comparable across workplaces under OSHA rules. Other methods exist, such as NIOSH procedures or EPA methods, but they are different standards or agency approaches and are not the official basis for OSHA personal samples unless OSHA specifically approves them as equivalents. ISO 17025 is a quality-management standard for labs, not a sampling/analytical method. So the appropriate choice is the OSHA Reference Method.