Biological Safety

Aerosol Transmissible Diseases

The Cal/OSHA Aerosol Transmissible Diseases (ATD) standard was adopted in 2009 to protect employees who are at increased risk of contracting certain airborne infections due to their work activities. The standard is codified in title 8 of the California Code of Regulations, section 5199

This California workplace safety law requires certain employers with employees exposed to aerosol transmissible diseases (ATD) to have effective written safety plans, provide protective equipment as needed, and train employees on safety procedures.

California Workplace Guide to ATD
Cal/OSHA ATD Fact Sheet

Scope of the Regulations with Regard to Laboratory and Field Research

Principal investigators with research involving any of the agents listed in “Appendix D: Aerosol Transmissible Pathogens – Laboratory” of Title 8, Section 5199 must establish, implement and maintain a written biosafety and exposure control plan that meets the requirements of subsection (f) on Laboratories. Appendix D includes human cytomegalovirus, shiga toxin-producting E. coli, and herpes simplex virus 1 and 2.

Additionally, § 5199.1 Aerosol Transmissible Diseases - Zoonotic explicitly covers operations involving the capture, sampling, or transportation of wildlife and operations involving samples, cultures, or other materials potentially containing zoonotic aerosol transmissible pathogens.

Principal investigators must complete a Biological Use Authorization (BUA) that describes the work procedures that minimize the production of aerosols, the use of personal protective equipment, cleaning and decontamination procedures, locations of emergency healthcare services, and the symptoms of infection for the main aerosol transmissible diseases or zoonoses associated with the project. The BUA can function as the written biosafety and exposure control plan, or the PI may complete the full length ATD Biosafety Plan template (linked below). The exposure control plan must be reviewed, updated annually and as needed, and filed with the campus biosafety officer to document compliance with the standard.


The ATD standard applies to specific workplace settings, and interim guidance from Cal/OSHA regarding the pandemic does not expand the scope of the ATD standard.

Campus leadership has developed the UCSB COVID-19 Prevention Plan, an overarching document for the entire campus describing general guidance and mitigation strategies to limit the transmission of the COVID-19 virus. In addition, a Worksite Specific Safety Plan (WSSP) was created as a template to assist departments with the development of their location specific work plan to ensure compliance with all local and state requirements for re-opening.

For questions on the ATD standard, contact the biosafety officer at 805.893.8894.
For questions on the Workplace Specific Safety Plan, please contact

Cal/OSHA Aerosol Transmissible Diseases Standard
Cal OSHA Title 8, Section 5199, Appendix D: Aerosol Transmissible Pathogens – Laboratory
Cal/OSHA § 5199.1 Aerosol Transmissible Diseases - Zoonotic
Full length Cal/OSHA ATD Biosafety Plan template, January 2020
ATD Addendum
Respiratory Protection Manual