Complementing Biosafety Levels With Societal Safety Levels

Biosafety level (BSL) classifications of biological agents have succeeded at minimizing occupational risk inside laboratories, but largely neglect the potential for onward transmission. As a result, many non-transmissible pathogens that could kill at most one individual per person exposed require greater containment than 1918 influenza, a virus that killed 50-100 million and might cause a new pandemic today. Laboratory workers are consenting professionals; the public is not. We recommend complementing BSLs with explicit thresholds for expected societal harm. Here we formalize Societal Safety Levels (SSLs) based on expected public fatalities per year, which we quantify from (i) estimated probability of laboratory release, (ii) likelihood of societal transmission, and (iii) consequence. SSLs would apply specifically to laboratory research with replication-competent potential pandemic pathogens, and would not restrict field surveillance, sequencing, or countermeasure development using non-replicating systems or pandemic-incapable agents. We find that applying the 0.1 expected deaths per facility-year standard common across multiple major-hazard industries to potential pandemic pathogen research would require marked safety improvements. Complementing BSLs with SSLs would establish enforceable accident-safety thresholds for pandemic-capable pathogens, bringing high-risk biological research into alignment with the quantitative safety standards that help other hazardous industries operate with public acceptance.