Thermal Imaging as Security Theater

Seems like thermal imaging is the security theater technology of today.

These features are so tempting that thermal cameras are being installed at an increasing pace. They're used in airports and other public transportation centers to screen travelers, increasingly used by companies to screen employees and by businesses to screen customers, and even used in health care facilities to screen patients. Despite their prevalence, thermal cameras have many fatal limitations when used to screen for the coronavirus.

  • They are not intended for medical purposes.
  • Their accuracy can be reduced by their distance from the people being inspected.
  • They are "an imprecise method for scanning crowds" now put into a context where precision is critical.
  • They will create false positives, leaving people stigmatized, harassed, unfairly quarantined, and denied rightful opportunities to work, travel, shop, or seek medical help.
  • They will create false negatives, which, perhaps most significantly for public health purposes, "could miss many of the up to one-quarter or more people infected with the virus who do not exhibit symptoms," as the New York Times recently put it. Thus they will abjectly fail at the core task of slowing or preventing the further spread of the virus.

Posted on May 28, 2020 at 6:50 AM • 33 Comments

Comments

RjMay 28, 2020 8:03 AM

Error rates and such notwithstanding, these devices are also your typical IoT: they probably have significant security vulnerabilities and open up the operator's network to attacks it otherwise would be safe against.

h2odragonMay 28, 2020 8:37 AM

Even if you've got an accurate thermometer, most mammals can run +/- 5 degF from normal temperature throughout the day for any number of reasons. People are a bit narrower range, but theres still folks walking around with 95 degF rest temperatures who have to have a fairly bad fever to get up to a range the doctors recognize.

kaest2May 28, 2020 9:41 AM

how technically accurate are these thermal imaging systems ?

what is the basic margin of error of the device itself (in degrees)?

the post is quite vague on this (and there's a dead link to one reference)

Are these devices useful under "some" routine circumstances?

samMay 28, 2020 10:47 AM

"They are not intended for distance from the people being inspected."

Missing a closing quote in an anchor tag?

nobodyMay 28, 2020 12:09 PM

Mass thermal scanning is not completely effective against SARS2 due to the long, pre-symptomatic but infectious, incubation time. It does, however, have some utility in deterring symptomatic people from knowingly going out in public and infecting others.

WayneMay 28, 2020 1:44 PM

There's also the problem that you can be sick with COVID-19, symptomatic or asymptomatic, and not have a fever. My workplace says everyone is going to have their temperature taken upon entry, which is patently ridiculous. If you wear a baseball cap during your commute, your temperature will be higher. Day off with pay?

WayneMay 28, 2020 1:46 PM

Sorry, meant to add that the symptoms for COVID are all over the place: you might have a cough, or not. You might have a headache, or not. Your big toe might hurt.

The only way to know is with a blood test. Temperature can indicate any number of things. I typically run about 2 degrees low.

Petre Peter May 28, 2020 2:13 PM

More money wasted on useless technology. At least it shows that something is being done.

A dubious personMay 28, 2020 2:59 PM

@ sam:

The quote about "intended for distance" might be referring (very awkwardly - perhaps Bruce lost some words here?) to the cameras having a limited useful range - that they only work properly at short distances. I agree that the statement seems like gibberish as quoted.

@ All:

IIRC, a similar thing was done at some large airports when SARS was still spreading, but I don't remember its effectiveness ever being rigorously investigated. It seemed to me at the time that it might be a "be seen to be doing something" exercise. In this new case, I don't see any evidence that it isn't entirely such an exercise. (Does anyone here know more about that precedent?)

It's also possible that this is a way to funnel more government response/stimulus funding to companies in the surveillance-IT sector. An investigation into the companies who are profiting from this might be interesting.

I'm quite disappointed in the NYT though: "up to one-quarter or more" is not a number. I didn't read the article this brain-fart came from but note that it's characterized as "Technology," rather than "Opinion" (where I would normally expect to see such bold innumeracy published).

Bill PaxtonMay 28, 2020 3:08 PM

I mean, it is true that such things are security theater in liberal democracies which don't care about the elderly and the vulnerable and are happy to let them die.

The simple fact is that all such governments have completely failed, so should not have even pretended to try and control the spread of the virus.

It's still an overgeneralization, because when you have an integrated system to protect people, and your nation is an ethnically homogeneous functional entity rather than a shopping mall, these things do work. The Chinese had them in airports as standard screening equipment years ago, because in combination with a generally responsible population that cares about each other, they do provide value.

metaschimaMay 28, 2020 3:20 PM

This Covid stuff is getting off the rails, or maybe it derailed a while back. There is so much misinformation out there, so much media-induced panic, so many people playing doctor, so much government mandated overkill measures that are ineffective, and of course many many many wild conspiracy theories. I can understand the need to come up with conspiracy theories because things don't make sense, and subconsciously people know this and cannot believe the official sources. I cannot understand the government measures against this and why they are moving towards using this as an excuse to implement a new apparently global dystopia. I mean that's what's happening right now, whether you like it or not. This isn't about the virus anymore, maybe it never was about the virus in the first place.

lurkerMay 28, 2020 4:44 PM

@Petre Peter +1

@Wayne, metaschima
this SARS-Cov2 is one crafty l'il critter. Sure we sequenced its genome real quick, but standing back and watching it work brought on mass attacks of confusion. The widely varying results of its passage through different countries reflects the diversity of human physiology and the rich tapestry of political governance (or lack thereof). It also shows how different administrations have interpreted "we, the people". See @Clive's postings on the needs of the many outweighing the wants of the few.

hatfeldMay 28, 2020 4:50 PM

If you wear a baseball cap during your commute, your temperature will be higher. Day off with pay?

If you're lucky. Most people don't get unlimited paid sick days, and many get none. Let's hope the check doesn't trigger a 2-week quarantine requirement.

So, a paid sick day now, maybe. When you actually get coronavirus in a few months, and they've stopped checking and you've used up all your days? Work while sick, and tell the complainers to use their own sick days.

brunoMay 28, 2020 7:44 PM

The link in «They are not intended for distance from the people being inspected.» does not work.

tzMay 28, 2020 8:02 PM

Now the scene from the original Fantastic Four where Jonnny is in the hospital and the nurse says "You're hot!" and he replies "Thank you, you're hot too!".

Time for a heated discusstion.

Clive RobinsonMay 28, 2020 11:04 PM

@ A Dub,

IIRC, a similar thing was done at some large airports when SARS was still spreading, but I don't remember its effectiveness ever being rigorously investigated.

SARS-CoV-1 back in 2002 os now officially "extinct" and this was achieved by strict control of infectious people, by "Thermal Imaging".

SARS-CoV-1 differed quite a bit in it's behaviour from the current SARS-CoV-2 that has given us COVID-19.

With SARS-CoV-1 you only became infectious to others AFTER your fever had started, and from what I remember there were no asymptomatic infection recorded. The problem with SARS-CoV-2 is that you are infectious prior to any symptoms thus a thermal imager is not going to see you as infectious, and something like 50% are currently "guestermated" as having symptoms so mild as to be effectively asymptomatic whilst being infectious. But even those who have tested positive via an antigen test only a minor percentage show a fever. Some are saying that "anosmia" the loss of smell or taste is actually a more prevelant indicator in some age ranges and women.

Further SARS-CoV-2 whilst being equally as infectious to women as it is to men, the severity of recorded cases effects is generally twice as bad in men as it is in women.

As others have pointed out "You can not fight what you can not see" SARS-CoV-1 was easily seen by thermal imaging, thus it was easily faught and is now extinct.

SARS-CoV-2 however is hard to see and thus because of our political laxity in North America and Europe made worse by the voices of vested interests we have not just a pandemic but one with near uncontroled community spread. The more neo-liberal the views of the elected officials in general the longer the period of procrastination and the worse the pandemic and the much worse the community spread has become.

We had an opportunity to make SARS-CoV-2 extinct like we did SARS-CoV-1, but it was frittered away by those who held and continue to hold faild neo-liberal mantra to be more important than human life.

Thirty years ago I used to ask people their views about the need for "Expanding the economy by destroying non renewable natural resources" those younger than myself felt it was wrong, but way to many people older than me thought not only was it a good idea but it was essential... I was a little too polite back then to point out each human life is a non renewable natural resource, including their life. The people I was asking back then who were so pro ecological disaster were those who benifited from "Thatcher's Britain" and now form the core of the biggest "at risk group" for COVID-19...

As the old saying has it,

    As Ye Sow, So Shall Ye Reap

Which has a bit of history behind it. For instance it appears in the Old Testement --Job 4:8-- as "they that plow iniquity, and sow wickedness, reap the same". Then around 50BC the Roman orator, philosopher, and statesman, Marcus T. Cicero, was recorded to have said "As you have sown so shall you reap". With it appearing again in the New Testement --Galatians 6:7-- as "whatsoever a man soweth, that shall he also reap.".

You get the idea that history has shown for quite some time that "self interested" things realy are just not a good idea and neo-liberalism as a creed to live by falls right in that historical warning.

As I've noted people have choice, especially when it comes to "Individual-v-Social Rights and Responsabilities". It should be self evident by now that "mankinds high estate" is actually based on a functioning society where "A rising tide lifts all boats". The neo-liberal mantra is a parasitic one of "take and not return". Thus they believe themselves to be "entitled" and that anything for society is "stealing from their pockets". Thus conveniently hiding behind the faux mantra that it is they more than others who are dependent on the good will of society, and can not survive without it. Remember any time a politician or talking head says something is essential to the economy, history usually shows that it has never been essential to mankind. Oh and just remember that our "growibg economy" is based on "accumulated debt", that is the "entitled" are "stealing from the future" which not they but generations of unentitled citizens we call society will have to pay back with the attendent loss of health, liberty, prosperity, and life expectancy. Thus the entitled believe they should have "their todays for your childrens, grand childrens and great grand childrens tommorows".

Unless of course their "entitlement" gives rise as it almost certainly will to another significant disaster, such as yet another global pandemic. Why would I think this will happen. Well nature has shown us it is actualy not "The strong that survive" but the "resilient" in fact more often than not "strength" is a short lived trip into an evolutionary cul-de-sac. Resilience is a form of stamina that is having sufficient spare capacity to survive short to medium term extremis. Nature usually shows that you need about 50% of your normal capacity as spare. That is you put about 1/3rd of your maximum capacity away for emergancies, that are going to happen.

To the neo-liberal "spare capacity" is "money left on the table" and thus a major "no no" in their view. In fact to maximize profit they believe in cutting capacity below what would be considered "normal" because the "laws of supply and demand" indicate restricted capacity means higher prices thus more profit...

The problem with less than normal capacity in the likes of healthcare means that their are insufficient resources thus people who could live infact die even in normal times. But come the winter cold people die each year needlessly, then there is the next crop of deaths to be reaped with flu... Now we have COVID-19 and the body bags have been pilling up in container vehicals in the side streets around hospitals. That's the result of the neo-liberal deliberate reduction in capacity thus resilience.

Based on what we currently know, with sufficient capacity in first world healthcare the deathrate of COVID-19 will be around 1%. However without healthcare it will be 5-6%. If the US can keep it's healthcare unsaturated then less than 3million US citizens will die of COVID-19. However if US Healthcare saturates as it is starting to do in Alabama, then 16million or more US citizens will die. That's the difference neo-liberal thinking does for you in the short term.

And that's before we start adding in the fact that there are going to be food shortages in the near future especialy in protein foods. In the first world this is likely to mean 50-200% price rises. In the second world malnutrition and reduced life expectancy with increased long term ill health. But in the third world expect significant deaths due to starvation, and rampant spread of avoidable disease...

This is where the neo-liberals get their "Double tap" with "disaster capitalism" where they will manipulate the market for more profit. If you think the vast profits Amazon are making at the expense of their employees are obscene as they say "you've not seen anything yet"...

Please note that Amazon are in the forefront of installing these heat sensing cameras allegedly for their "employees benifit" it's actually nothing of the sort. Amazon are doing it for two reasons,

1, To reduce Amazon's legal liability to their employees.

2, To move their people and purchase tracking technology into the work place for "employee evaluation" prior to termination.

Yes just like those "crotch facing heat sensors" found under desks in a british newspaper office, these heat sensing devices will be used to reduce wages and job security of employees all in the name of "not leaving money on the table".

GarabaldiMay 28, 2020 11:22 PM

They will create false positives,

They will create false negatives,


Any useful* test will have false positives and false negatives.

Argue that the error rates are too high. Or argue that error rates haven't been measured. But arguing "errors exist" is pure Nihilism.

* "Reject everything" test has zero false positives, "accept everything" has zero false negatives, but neither of these is useful. Using "errors exist" as a test is a thinly disguised version of "reject everything"

ATNMay 29, 2020 3:40 AM

@ Bill Paxton:
> I mean, it is true that such things are security theater in liberal democracies which don't care about the elderly and the vulnerable and are happy to let them die.

Why "in liberal democracies", other government forms are doing better?

Also, elderly generation did not "pay their way in life", leaving massive debts at the government level to be paid by their children, under-inverting in health systems, leaving their children pay for their retirement, and now amassing more debts to keep them alive a bit longer (number of deaths from COVID-19 seem low for below 60 year old). At some point, if you are alive, you need to accept you will die one day.

> The simple fact is that all such governments have completely failed, so should not have even pretended to try and control the spread of the virus.

The reason to "slow down the spread of the virus" is to not overflow the health system, which I do agree with.

Like any virus, now that COVID-19 has spread to much to totally suppress, the only way forward is heard immunity, and I would be quite happy to catch it (and hopefully survive) - so I know my body will be able to handle it (or its mutations) in the future.
The likeliness COVID-19 will mutate seems quite high, due to the number and diversity of people infected, COVID-19 will find a way to "survive" (even if, being a virus, it is not technically alive). Viruses are on earth since probably the happening of multicellular lifeforms.
Finding a vaccine will probably only protect against the current form of COVID-19, not as efficient as being directly exposed to COVID-19.

Finally, I still wonder why all this theater appears today, and did not happen in 2014/2015 with the very high number of death due to the flue that year (61,000 in USA).

IsmarMay 29, 2020 4:37 AM

While out shopping with my children earlier this week, as a condition of entry to one of the clothing stores, we were all scanned by a hand-held infrared thermometer. Did I feel safer inside the store knowing no other customers had increased temperatures at that time- yes. Was a really safer - probably no. As with many other things, it is all about perception, and from that perspective these measures can serve as a calming mechanism in uncertain times but that is where their usefulness stops.
Plus, manufacturers of these devices are making a killing (so to speak) which cannot be bad for the economy 😉

OnlookerMay 29, 2020 7:50 AM

@Bruce

Your HTML is messed up. There's a double quote missing at the end of the HREF attribute in the link for the first bullet point. That's why people keep saying the link is dead. The missing double quote is also making the first and second list items merge. Also you've got a bunch of unnecessary P tags in the middle of the list.

For everybody else, here's how it should look:

These features are so tempting that thermal cameras are being installed at an increasing pace. They're used in airports and other public transportation centers to screen travelers, increasingly used by companies to screen employees and by businesses to screen customers, and even used in health care facilities to screen patients. Despite their prevalence, thermal cameras have many fatal limitations when used to screen for the coronavirus.

  • They are not intended for medical purposes.
  • Their accuracy can be reduced by their distance from the people being inspected.
  • They are "an imprecise method for scanning crowds" now put into a context where precision is critical.
  • They will create false positives, leaving people stigmatized, harassed, unfairly quarantined, and denied rightful opportunities to work, travel, shop, or seek medical help.
  • They will create false negatives, which, perhaps most significantly for public health purposes, "could miss many of the up to one-quarter or more people infected with the virus who do not exhibit symptoms," as the New York Times recently put it. Thus they will abjectly fail at the core task of slowing or preventing the further spread of the virus.

ApokrifMay 29, 2020 10:09 AM

@Bruce Schneier:
"They will create false positives"
"They will create false negatives"

Nobody says it's a silver bullet. Measuring body temperature should be done only in addition to other measures, or in certain contexts (e.g., people with high temperature could be sent to PCR or antibody testing, or could be requested not to visit old people, or to work from home for two weeks).

vas pupMay 29, 2020 1:56 PM

@all:
What is the base line for so called normal temperature?
Is average temperature for health population considered normal temperature? then average temperature of the patients in the hospital between autopsy unit and intensive care is normal-:)

lurkerMay 29, 2020 6:27 PM

this is a very wierd virus, probably the wierdest infection we've seen, ever... more than half of patients catching this having no symptoms whatsoever... such a broad range [of symptoms] we just don't understand why that is...
The first two quotes were told by colleagues to consultant clinical virologist Dr Chris Smith, the last is his own admission. He also links <Care Homes - dementia - APOE lipid control genes - Covid19 susceptibility>. Note that APOE is also significant in coronary diseases suffered by many Care Home patients. A Thermal Camera can't see genes...

https://www.rnz.co.nz/national/programmes/saturday/audio/2018748649/chris-smith-covid-19-testing-and-treatment

Jesse ThompsonMay 29, 2020 6:37 PM

I would hazard that one big difference between "IR measurement of potential fever is easily gamed" and "XYZ measurement of terrorist activity is easily gamed" is that the latter involves human antagonists as the primary threat model. They can directly study the countermeasures and then work to bypass them.

But in the case of COVID the antagonist is a virus. Given enough time a virus can also work to learn from countermeasures, but neither as directly nor as efficiently as a human terrorist.

Using thermal imaging to detect fever in a crowd will be imperfect. Sometimes it will detect a fever where there is none, or miss a fever that walked by. Sometimes it will detect a fever not caused by COVID, or allow folk to slip by who have contagious COVID but lack a fever.

But it sounds far more likely to me that this system would catch a person with fever who has COVID than it would that the TSA would ever nab a terrorist human. So the question boils down to how many valuable hits can it make, and how does that compare to the strikes that it allows through or the foul balls of safe people that it flags?

Especially when combined with other screening methods that have different strengths and weaknesses, this approach in general ought to be a valuable line of defense. Pull people aside caught by the thermal imaging for some skin-contact temp-taking. Politely ask them if they have noticed any symptoms, have been near others who have, have been traveling recently, etc etc.

If you pull somebody aside and skin temp is normal, they don't report anything unusual then that's strong evidence the thermal camera got them wrong in it's own measurement. Pull them aside and they're coughing and plem coming out their nostrils, send them home.

It's only security theater when you make a theater out of it. If you can use it to improve safety by some significant margin without significant expense, then it's what I would call garden variety security.

Clive RobinsonMay 30, 2020 4:31 AM

@ Jesse Thompson,

So the question boils down to how many valuable hits can it make, and how does that compare to the strikes that it allows through or the foul balls of safe people that it flags?

Depends on who you ask but,

1, Atleast 50% of people are asymptomatic.

2, Of those who eventually brcome symptomatic less than a third show fever.

3, You are infectious and shedding virus upto seven days before a you have a fever.

So less than one in six infectious people and quite some time after they have been infecting others.

Not exactly a good batting average to put it politely. Apparently loss of smell is a more reliable indicator and stands out as a much more distinct marker especially in the young and quite socialy mobile, where you would expect "silent spreaders" to be most likely.

GarabaldiMay 30, 2020 12:33 PM

@ Clive Robinson

So less than one in six infectious people and quite some time after they have been infecting others.
Not exactly a good batting average to put it politely.

But a pretty good career shooting percentage for a hockey player.

We do not know enough about the epidemic to know if we are playing baseball, hockey, go, or quidditch.

Moreover we should stop waiting for a magic bullet. Even a fairly weak measure can be a useful part of a coordinated response if it is cheap enough and complements other measures. R=1.05, result misery; R= 0.95, result less misery.

David EldenMay 30, 2020 1:53 PM

Surely this is hygiene theater[re] not security theater??
Dave.

lurkerMay 30, 2020 7:28 PM

security [mass noun] 1. the state of being free from danger or threat; Oxford English Dictionary

The security of civilization depends on a healthy active population. A pandemic that threatens that health is a security problem. @Bruce can moderate discussion beyond info-tech security if he wishes.

RjMay 31, 2020 7:41 AM

@lurker: "The security of civilization depends on a healthy active population. A pandemic that threatens that health is a security problem."

And a governmental response to a pandemic that limits activity is likewise a security problem!

The governmental response so far has been highly destructive to the global economy. This is not by accident. The purpose here is to destroy the "old" economy so that a "new" economy can be introduced. This new economy is envisioned to be a single unified global economy under a single point of control. Those who desire such a system say that it will be better. I disagree for reasons that are off topic for discussion on this forum; nevertheless, it should be mentioned that this is a very real possible reason for the governmental responses we have been seeing.

lurkerMay 31, 2020 11:28 AM

@Rj

This new economy is envisioned to be a single unified global economy under a ...
"... multilateral governance system" in the version I heard.

But most governments have sleep-walked into it, and will be presented with an offer they cannot refuse.

A dubious personJune 4, 2020 3:19 PM

@ Clive:

Thanks for the very informative compare-and-contrast with SARS-CoV-1.

Leave a comment

Allowed HTML: <a href="URL"> • <em> <cite> <i> • <strong> <b> • <sub> <sup> • <ul> <ol> <li> • <blockquote> <pre>

Sidebar photo of Bruce Schneier by Joe MacInnis.