Agree fully we need an inquiry. Lots that needs documentation if only to aid another group of clean air advocates in 25 years.

But to be clear. Anyone who asserts that evidence is poor about N95 effectiveness versus bioaerosols, is confirming they are not conversant with science The CSA standard on respiratory protection has been in place for decades. It EXPRESSLY sets out what real science supports as needed for protection against bioaerosols.

Z94.4-18 it’s all there.

It’s even presented through control
banding, nice graphics so easy to understand.

https://twitter.com/sameo416/status/1619478705591705600

One thing I've seen PH types not get is how difficult it is to draw firm conclusions from trend data involving very, very low levels of events.

Aviation is exceptionally safe, and you're not going to see a big trend shift over years. What you need to do is watch the weak signals

https://twitter.com/GYamey/status/1777063423743783311

Those weak signals are already there and recognized by bodies like the FAA, who are acting.

To throw out 'safest year ever' with what's going on in the aviation industry is absolute junk science.

It's very hard to determine causation with weak signals. As we've seen in the

A few words about the NTSB preliminary report into the Alaska Air door plug departure on 5 Jan 24, Boeing 737-9 Max, N704AL.

NTSB site if you want to read the report or review the photos: ntsb.gov/investigations… First, calling this 'rapid' decompression, so not technically 'explosive' decompression. The definition has to do with rate of change of pressure.

Missing door. Can see insulation (yellow) and the structural pads - 2 upper left, 1 upper right - of the door. 12 of those in total.

Alaska Airlines flight out of Portland rapid decompression after mid-rear fuselage lifted door blows out. 737 Max-9

Made about 16,000 ft MSL so not as serious a pressure diff as it could have been.

kptv.com/2024/01/06/pla… This isn’t an exit. It’s a structural doorway that’s fixed closed and covered with an interior wall panel. Periodically inspected.

This is an unusual structural failure. Unusual^2. It looks like the frame is gone.

Some concerns starting with use of far uv "skin safe" lights. I expect the exposure limits will be increased again with research, but right now it's possible to blow through those limits with a light of any power (say 10 or 12 watts and up).

Calculating incident energy and exposure can be easy, but it can also be complicated.

I can't teach this in a thread, but will try to illuminate the complexities involved.

A simple light source that emits constant energy in all directions it illuminates can be treated as an isotropic source.

Reflects how spectacularly poor we are at assessing risk.

When someone says I’m ok with the risk, it usually means they feel safe, not that they’ve performed a formal risk assessment.

No one I know has been disabled in an MVA, doesn’t lead me to conclude there’s no risk.

https://twitter.com/brownecfm/status/1727278534560035131

This is the reason cvd is causing such widespread harm, the serious immediate impact is relatively low, and the longer term impacts aren’t usually immediate.

If 50% were dying while visibly hemorrhaging, there’d be more urgency broadly.

Think 1918 flu or the Plague.

Bunch of comments about the “values before science” report just released.

Trying to satirize it and discovered I can’t. It’s a problem. Here’s why.

CW: colonial violence Setting up that ‘values before science’ is a problem requires the assumption that science itself contains an ethics/moral value system that stands alone.

I’m not sure that’s accurate.

And in cases where we ‘follow the science’ our cultural values allow grave harms without pause

"For the pandemic, everyone looked to medical doctors and public health officials for guidance, and they certainly have expertise in what's happening with the virus when it's in your body and what we can do about it on a population scale. But I think they were not savvy to what we can do in the indoor environment to reduce the risk of transmission, because they weren't really aware of the mechanics of transmission.

There's a short Youtube video going around of an AME explaining why aircraft ventilation is so good and aircraft cabins are free of contaminants. I did some checking to get ready for @TheReSisters2 @MaryJoNabuurs @coopSpeak community tonight. Sharing my fact check here. AME = aircraft maintenance engineer, holder of a federal Transport Canada mechanics license.

I've done 3 threads looking at cabin ventilation and disease transmission from published literature. First is here:

https://twitter.com/sameo416/status/1546895587374600192?s=20

Listening to the radio today, heard Midnight Oil's song The Dead Heart. Listened to them since college, but I'd never really heard the lyrics of this song before.

I knew their hit "Beds are Burning" was about Indigenous rights. These lyrics really caught me today. We carry in our hearts the true country
And that cannot be stolen
We follow in the steps of our ancestry
And that cannot be broken

A thread about the movement aka safety differently, and how this is another thing industry could teach public health and infectious disease physicians.

For decades the prevailing safety method was based on compliance. Cause if you reduced errors to zero, there’s be no accidents! This was loosely based on early research that said if you could reduce near miss or minor injury accidents to zero, you’d eliminate serious and fatality accidents.

Again, cause it’s all about eliminating errors.

But people noted that while the low impact incidents were reduced,

An addendum to that earlier thread on risk assessment.

First, our default as humans is to be very very poor at understanding risk. This is apparent in most people’s personal lives or while they’re driving.

One reason - we do things without getting bit and conclude they’re safe

https://twitter.com/sameo416/status/1649617882597453824

Normalization of deviance is the technical term. We do a particular thing repeatedly and conclude it’s safe because nothing happened, when the reality is the cheese holes just didn’t line up for us.

Classic example involving pilot ejection seat 🪂.

Some comments popping up from people who aren’t denying LC and enduring impacts from c-vid, but are asking seemingly rationale questions about prevalence and endurance.

It reveals a basic misunderstanding about risk mitigation, something we’ve seen ++ in medical responses. If you have credible evidence of a potential risk, what you do not do is say, “we need to understand this risk better before we act”. This has been the primary medical policy response to c-vid in NA.

“We need high quality evidence”.

That’s not the way risk management works.

Had the honour today of helping to obligate new graduates at the UofA.

This is the ritual calling of an engineer. A ceremony written by Rudyard Kipling originally, updated a lot to modernize language and content. The goal of the ritual is to reinforce the obligations engineers have to society and to ethical behaviour.

It reflects the high standards expected in protecting the public welfare, also captured in legally binding codes of ethics.

I had the privilege to speak to an engineering class yesterday about Settler and Indigenous cosmologies. "Immiscible World Views" is the title.

When I first gave that talk a Dean of Engineering asked me if I really believed that these were "immiscible" (un-mixable) cosmologies. I do. I also see that many Indigenous are able to operate in bi-cosmic space, as we live immersed inside a different culture.

This is sort of like when I lived in Germany. I figured out how to navigate 'those curious German ways' quite well, and even to speak the language.

Some engineering method based comments on the Loeb mask study, and by extension on the Cochrane review weighting the same. Engineering method. Our work is highly empirical. Even numeric models that approximate reality are expected to provide outputs that are accurate and precise with respect to what is being modelled. This is how most design work is done virtually today, with physical items later.

It’s super encouraging to hear erudite commentary from a member of the medical community.

I’m outside the esoteric circle (Fleck) and easily dismissed as an ignorant engineer. In spite of becoming quite familiar with EBM and engaging in many discussions with EBM experts. The reverse is not true. The MDs who accuse my ilk of epistemic trespassing or trying to tell them what to do invariably have zero knowledge of engineering or natural science and our methods, and are not involved in interdisciplinary teams where that understanding can grow.

This is awesome.

I’ve been thinking about gravity waves lately as well. What do we say about a “gold standard” promotion that has absolutely no predictive power? As an engineer, I’d call it a weak statistical analysis only, as it models and predicts nothing.

https://twitter.com/toshiakima/status/1627184313593909248

The many MDs who make disparaging comments about engineering maybe need to consider that our methods allow us to predict things extremely accurately. This is how we make things that last 100 years. And how we do amazingly complex designs on paper without needing 100’s of

Was reflecting (after meeting some of my heroes two weeks back) on what it is that motivates people to keep advocating. In several discussions I’ve heard about exhaustion, some despair, with the constant battling to push aside misinformation. And this isn’t a my opinion vs your opinion type dynamic. Much of what is being resisted is based in bad science that does not reflect the consensus in the community. Eg, that Covid is spread mainly by large droplets. This is literal flat earth science and has been for decades.

A push-back on those who continue to say randomized controlled trials (RCT) are the "gold standard" for answering questions in science.

They are not. This statement gets tossed around often today, some are just careless, but others actually believe this is true. My first comment - science is a very broad field. If you're making pan-science assertions like that, chances are you're displaying your ignorance of other disciplines.

Over 35 years in engineering, practiced several discrete disciplines, and I don't know engineering that well.

This is a good comment.

Have to object to the broad assertion that RCT are the gold standard in science. They are not. Maybe specific ?’s of medical science, but there is a lot of science beyond medicine that considers RCTs to be poor and weak methodology when applied elsewhere

https://twitter.com/dr_kkjetelina/status/1623015798498541568

This line from the substack, “Only included randomized control trials (RCTs). This is typical for meta-analyses as RCTs are the “gold standard” for scientific questions.”

RCTs are not the gold standard for scientific questions. We need to be cautious about such broad statements.