How long should industrial hygiene surveys be kept on file?

How long should industrial hygiene surveys be kept on file?
This was our response:


The intent of industrial hygiene surveys is to identify possible risks to worker health and the need for further evaluating and testing to determine if there is a risk of overexposure and regulatory compliance issues. Risks can include:

• Air Contaminants
• Chemical Hazards
• Biological Hazards
• Physical Hazards (noise, heat, radiation)
• Ergonomic Hazards

Employee exposure and medical records must be maintained for the duration of the worker’s employment and for 30 years from that date (29 CFR 1910.1020). Employee noise exposure records must be maintained for 2 years (29 CFR 1910.95).
Recognized hazards covered under the General Duty Clause of the OSH Act—ergonomics and heat illness—may also fall under the exposure and medical recordkeeping requirements.
OSHA will review baseline surveys for safety and health hazards, including all industrial hygiene sampling records during an inspection.