Overall it looks to me like Young is trying to give a high level introduction to biosafety, including giving specific examples of historical failures to explain why you care how the air is flowing. Then you’re responding by citing papers that say “better to manage airflow this way and not this way” as if they conflict with her explanations, but I don’t actually see conflicts?
Fair! The post was supposed to be a little bit of a call to being curious and controlling for a thinker’s big idea rather than confidently pointing to conflicts. It is also worth noting that optimal number of biosafety failures (and maybe even pandemics?) is not 0. As Bryan Caplan said:
Whenever there is a disaster, the normal reaction is, “Something has to be done to stop this from ever happening again.” Again, the question is: Maybe we should just stay the course, because this is the right number of disasters to have? Which horrifies people. But look, we shouldn’t have earthquake codes so strict that no building ever collapses, no matter what, because the effect on housing costs would be astronomical. So why don’t you tell me what is the correct number of houses to collapse in earthquakes [or airflow issues in biosafety labs]? And then we’re only going to cover it in the media if we exceed that number. You just imagine people’s heads exploding, like, “No, we have to cover every single one so that we can have the proper reaction!” This proper reaction is what makes housing costs too high.
Of course, it still makes sense to be aware of the risks, and I think it is great that Alison has contributed to that! I have added the above quotation and sentences before and after it in this comment to the post.
Below are some quick replies to the other parts of your comment, but I wanted to say the above 1st because for me it is the most important part.
Note also that when Young talks about controlling air flow she’s talking about something much broader than directional airflow. That also includes things like biosafety cabinets and positive pressure suits, and I don’t think anyone is saying these aren’t critical tools?
I have not looked into that, but I guess they are important.
I don’t think these are in tension? The Bennet study is talking about how to design BSL-3 labs, and Young is describing a situation where a CDC lab wasn’t being operated as designed. It reads to me like after an accident the CDC lab’s airflow management wasn’t operational at all. This would still have been be a serious issue if the lab had been designed along Bennet’s recommendations, focusing on inflow velocity.
Right, directional airflow should have been working, but Alison also seemed to imply there is a need for a differential pressure gradient, which is in tension with Kurth 2022 saying:
Only a 2005 study by (Bennett et al.,2005) addresses the relationship between negative pressure and protection from cross-contamination in BSL-3 laboratories in an evidence-based manner and concludes that pressure differentials has no effect on protection from cross-contamination.
Fair! The post was supposed to be a little bit of a call to being curious and controlling for a thinker’s big idea rather than confidently pointing to conflicts. It is also worth noting that optimal number of biosafety failures (and maybe even pandemics?) is not 0. As Bryan Caplan said:
Of course, it still makes sense to be aware of the risks, and I think it is great that Alison has contributed to that! I have added the above quotation and sentences before and after it in this comment to the post.
Below are some quick replies to the other parts of your comment, but I wanted to say the above 1st because for me it is the most important part.
Right.
I have not looked into that, but I guess they are important.
Right, directional airflow should have been working, but Alison also seemed to imply there is a need for a differential pressure gradient, which is in tension with Kurth 2022 saying: