error as “B” (one per 100 years or even less frequently) does not align with much of what we know about human error rates and the ability of human beings to defeat sophisticated engineering solutions. As another example, the Committee does not believe that the assumptions made about PAPR (powered air purifying respirator) failure rates on p. 11-8 are realistic. This could be addressed using a sensitivity analysis to see whether an increase has any effect on the overall assessment.
The statement on p. 11-9, lines 24-26 that an undetected needle stick would affect only one worker and is “estimated to be in frequency category B (one in 100 to 10,000 years)” is a strong statement that should be explained. (See also discussion under Chapters 4 and 8, above.) Similarly, on p. 11-27, line 31, the statement that there is “no risk of person-to-person transmission” is overly strong and in fact contradicts cases sited in chapter 3 of person to person transmission (e.g., for cutaneous anthrax). It would also be helpful to point readers to the source (in the report) of analysis and information on which conclusions about “operational information” are based (p. 11-29, line 5).
As noted earlier, the Committee finds that this penultimate draft of the RA is a substantial improvement over past documents we have reviewed. In the terms in which our Statement of Task is written, the RA is now closer to reaching its goal of being “scientifically and technically sound” and, in general, addresses the concerns raised in the original NRC review of the “DSRASSA” document in 2007. While there are many approaches to preparing a risk assessment and in some aspects the Committee would have used approaches other than those found in this draft, this is no reason to fault the document. It is clear that NIH and the Blue Ribbon Panel have gone to unprecedented lengths to improve the risk assessment for the NIEDL and have made substantial advances. It is the Committee’s hope that the comments in this letter report will be taken as suggestions for improving the final draft report further. We wish NIH well as it moves into the next phases of this complex process and prepares for the solicitation of public comments on the final draft. It is the Committee’s view that no further advice from this group would be useful nor should it be required.