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Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by cryoshon on Tuesday October 20, 2015 @04:17PM (#10421537)
I don't consent to any form of non-necessary irradiation, regardless of the quantity.

Not sure why the NYPD gets to irradiate me without consequences (which constitutes a search of my person, without a warrant or consent, not to mention having a potential medical impact on people not suspected of any crime) when we can hardly point cameras at them despite it being explicitly legal.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by randyrand on Tuesday October 20, 2015 @05:21PM (#10421896)
Your consent is not needed even for unnecessary radiation. If I shine my high beams on your car, or have a cellular phone call next to well - too bad. I'm entitled to bombard you with radiation if I want to.

But for the sake of argument Ill assume you just care about ionizing radiation (UV, Xray, Gamma, Neutron, etc). In that case I agree consent should be needed for medium to high dose. It's unfeasible to get the consent of everyone for low doses (x-ray machine x-rays can travel for miles and theoretically infinitely far).

In this case it appears the dose is only about that of eating a banana. Hard to argue you need to consent to that for radiation concerns unless you also agree that everyone should consent to every xray scan that every hospital executes, or every time your colleague brings in bananas to work. Privacy concern is valid though. Radiation one is just fear mongering if OP is correct.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @05:33PM (#10421967)
That's PER SCAN. Do you think the Police roll up, do a scan, and then take off? No. They're sitting there scanning constantly (most likely), so to use your analogy, that's a lot of banana eating.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by jostmey on Tuesday October 20, 2015 @11:25PM (#10423506)
And are we assuming that the person is inside a metal vehicle? What if someone is outdoors?

How much radiation does this scanner actually emit? The numbers are meaninglessness without more information. Why doesn't the manufacturer just publish the hard numbers?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by jsprogrammer on Tuesday October 20, 2015 @06:56PM (#10422426)
Yep, let's see the actual discharge history of the vans.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by AnimalMuppet on Tuesday October 20, 2015 @05:56PM (#10422084)
Even more banana eating for the cops running the thing...
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by pohl on Tuesday October 20, 2015 @06:45PM (#10422376)
...assuming there's no shielding between the equipment and the cabin, right? Turns out there is shielding:

"Law enforcement officers operate the system in conditions of complete safety from inside shielded cabins." (Source: http://www.nethun.it/index_en.php?sez=security_en&sec=rm )

Don't miss this delicious advertisement video:

https://www.youtube.com/watch?v=iABPKd0vFxQ

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @05:58PM (#10422102)
Did you even read the article?

     can be operated remotely from more than 1,500 feet 
Yeah, totally dangerous for the cop </sarcasm>
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by AnimalMuppet on Tuesday October 20, 2015 @06:04PM (#10422140)
Can be, yes. How often will it be? How often will it be operated remotely, and there's no other police in the immediate vicinity doing traffic control or some such?

[Edit: the article also talks about scanning the inside of a house in 15 seconds. That's not going to happen if they drive up the van, park it, get out, walk 1500 feet away, scan the house, walk back... (Yes, I know, they can drive away and back in another vehicle. It's still not likely to be operated remotely in that usage - all the activity makes it too conspicuous.)]

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by coldtea on Tuesday October 20, 2015 @06:21PM (#10422233)
>Can be, yes. How often will it be?

The answer can even be ALWAYS, if remote controlling it is mandated by protocol.

>How often will it be operated remotely, and there's no other police in the immediate vicinity doing traffic control or some such?

That doesn't come into play at all. Do you think those kind of surveillance happens in busy streets with traffic control cops dancing around?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by AnimalMuppet on Tuesday October 20, 2015 @06:26PM (#10422256)
Top-level comment by sandworm101:

> They are not hard to spot. Watch the media entrances of events, where the on-location vans drive through. Look for where traffic is routed through a single lane. Inevitably they will route traffic past an unmarked van. Or, look for an unmarked van trolling any parking lots within any security cordon.

That "look for where traffic is routed through a single lane" makes me strongly suspect there's going to be traffic officers in the very near vicinity.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by coldtea on Tuesday October 20, 2015 @06:46PM (#10422380)
>That "look for where traffic is routed through a single lane" makes me strongly suspect there's going to be traffic officers in the very near vicinity.

In that case those "traffic officers" will be further down directing traffic to the van, not in the van's target.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by hamiltonkibbe on Wednesday October 21, 2015 @12:43AM (#10423767)
"Don't worry, the spec'd dose rate from this Therac-25 is way below Denver background levels... No need for a dosimeter here..."
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by Gibbon1 on Tuesday October 20, 2015 @07:25PM (#10422555)
Someone doesn't understand the difference between ionizing radiation and non-ionizing radiation.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by wavefunction on Tuesday October 20, 2015 @08:40PM (#10422864)
Perhaps the issue isn't as settled as you might think.

Please refer to the link I posted just above this for a study from MIT linking non-ionizing radiation to permanent damage to cellular DNA.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by Gibbon1 on Tuesday October 20, 2015 @11:34PM (#10423546)
The effects of ionizing radiation are pretty well settled. Non-ionizing, people have been unsuccessfully chasing that ghost for decades.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by YeGoblynQueenne on Thursday October 22, 2015 @08:06PM (#10436038)
I'm not really sure about that. UV rays from the sun are not ionising radiation, are they? I mean the ones that are known to cause skin cancer.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by mattkopecki on Tuesday October 20, 2015 @05:34PM (#10421971)
> If I shine my high beams on your car, or have a cellular phone call next to well - too bad. I'm entitled to bombard you with radiation if I want to.

I think this is a really good point, actually. Do all these electronic devices need to be FCC approved? And if so, how do these vans' dosage gybe with any FCC regulations?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by randyrand on Tuesday October 20, 2015 @05:37PM (#10421985)
All electronics yes. But (nearly?) everything emits radiation. Candles, fire, your body. and those things are not FCC approved.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by bediger4000 on Tuesday October 20, 2015 @06:28PM (#10422273)
That's equivocation at its best. Candles do not emit ionizing radiation in measurable quantities. X-Ray machines do. There's a huge distinction, similar to the distinction we make between shining an incandescent bulb up at a helicopter or passenger plane, and shining a laser pointer.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:07PM (#10423185)
So we regulate X-Ray machines keep the radiation leak below the level that would oblige to ask people in the area for consent. GP has a point. The concern in this thread is based entirely on the notion that "radiation" is a scary-sounding thing.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by CydeWeys on Tuesday October 20, 2015 @10:46PM (#10423371)
No, the concern in this thread is based entirely on the notion that innocent people are potentially being exposed to X-rays, without their knowledge or consent.

You're arguing against a strawman. HN commenters aren't idiots. The technology in question is using ionizing X-rays, which can have harmful health effects.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:55PM (#10423409)
I never assume HN commenters are idiots. That's the very reason I hang out here - I learn a lot from what people say in this place.

Having said that, this thread is dominated by commenters who refuse to do the math. X-rays sound scary but they aren't death rays; if you add up the numbers you'll see that it's not even worth to talk about them here. There's higher probability they'll harm someone by introducing more cars onto streets.

EDIT: oh, I forgot. The Chart: https://xkcd.com/radiation/.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by learc83 on Wednesday October 21, 2015 @12:39AM (#10423751)
What if there is a machine malfunction? Lack of proper maintenance? Operator error? Sure there should be fail-safes, but accidents happen.

Bouncing around in the back of a van, something goes wrong. Instead of a rapidly moving beam of x-rays that doesn't stay in one location long enough to cause problems, you get a focused beam.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Wednesday October 21, 2015 @01:11AM (#10423830)
Those are fair concerns. I haven't seen the estimate for maximum amount of radiation the X-ray machine could generate when malfunctioning. We need those to see whether or not there is something to worry about.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by learc83 on Wednesday October 21, 2015 @10:34AM (#10425657)
If it works anything like the backscatter machines the TSA was using (rapidly moving beam), a failure mode like what I mentioned is definitely enough to be dangerous. There was a physics professor from Arizona state who said that the TSA machines could even cause radiation burns if the fail-safes failed and the beam kept going while stuck in one position.

It many not work that way though. Who knows? That's the problem with being secretive about the whole thing. They don't publicly release data on potential malfunctions.

One of my biggest concerns is the amount of training the operators receive on recognizing and reporting potential malfunctions. I suspect it's not sufficient, but again who knows? They won't talk about it because terrorists.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Wednesday October 21, 2015 @11:27AM (#10426087)
I agree, those are causes for concern. It doesn't matter if they're using radiation - whether they'd be using chemicals, biological agents or voodoo, as the issues of proper training and secrecy around a device that fails dangerously is a serious matter. They should be opposed as everything from waste of tax money to being a public safety issue, just not because of the radiation per se.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by CydeWeys on Wednesday October 21, 2015 @08:15PM (#10429728)
I disagree. I think it is worth it to talk about them, for three main reasons:

1. Even if this machine only gives off radiation equivalent to, say, a dental X-ray, I still did not give my consent for it, whereas I did give my consent for the dental X-ray. Consent is important. There are a lot of things that are OK with someone's consent, but not OK otherwise, and we don't have the right to make these decisions for someone. 2. Medical X-rays have positive expected trade-offs for receiving the dose of radiation. Compare this to an X-ray police van than I happen to walk past; there's not really any argument that can be made for why my exposure to this X-ray radiation is worth it for me. 3. The machine can malfunction, or be used improperly, and give off substantially more X-ray radiation than expected or designed. Safeguards are in place for other uses of X-ray to protect against this, e.g. you wear a lead apron to protect the rest of your body during a dental X-ray, and the assistant taking the X-ray leaves the room entirely. Safeguards of these sort aren't possible with the presence of an unknowing public.

There's also of course the entire privacy aspect that we haven't even delved into yet, but the health issues alone are concerning.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by YeGoblynQueenne on Thursday October 22, 2015 @08:02PM (#10436019)
"radiation" is a scary-sounding thing.

That's because scientists who know about this sort of thing have repeatedly warned the public that it can kill you dead in a very scary manner.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by mattkopecki on Tuesday October 20, 2015 @07:50PM (#10422673)
So, in any case, the FCC has set limits for acceptable amounts of radiation exposure from certain classes of the electronics that we find all around us every day, and I guess I was just wondering how those limits would compare to the radiation dosage of these vans.

It might not be approved by the FCC, but if it's equivalent to something that the FCC would allow you to carry around in your pocket anyway, it's hard to justify being upset these vans driving around from the perspective of being exposed unawares to their radiation.

There are a number of other reasons to be upset about such vans, though.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by retrogradeorbit on Tuesday October 20, 2015 @08:54PM (#10422913)
Go point a laser directly in your open eye. Don't worry. Any blindness you endure is FCC approved.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:09PM (#10423194)
A banana dose is equivalent here to light bouncing from my skin directly in your open eye. Does my skin need to be FCC-approved?

I didn't expect HN of all places to fall into "radiation sounds scary therefore its bad for you" line of thinking.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by retrogradeorbit on Wednesday October 21, 2015 @02:29AM (#10423993)
So why don't you try the laser experiment. Use a 1 milliwatt laser. That's _less_ energy than the light bouncing from your skin. That's nothing. And it's non ionizing radiation. So it's totally safe. Point it right in your eye. See what happens. By the completely over simplified thinking that you are undertaking here you will be fine. Right?
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Wednesday October 21, 2015 @02:55AM (#10424050)
I meant that light bouncing from skin to eye is a proper analogy for banana dose.

But since you challenge me - I shined the usual ~5mW red laser pointers many times straight into the eye, and had strangers shine them at me as well. It's annoying, but it doesn't hurt. My vision is ok. I'm totally fine.

See also: https://en.wikipedia.org/wiki/Laser_pointer#Eye_injury.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by digler999 on Wednesday October 21, 2015 @12:52PM (#10426682)
> It's unfeasible to get the consent of everyone

then don't do it.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by YeGoblynQueenne on Thursday October 22, 2015 @07:54PM (#10435982)
>> It's unfeasible to get the consent of everyone

a.k.a. "I didn't ask because I knew you would say no".

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TrevorJ on Wednesday October 21, 2015 @11:15AM (#10425993)
The difference is it's invasive. You couldn't shine a flashlight up people's skirts.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by jegutman on Tuesday October 20, 2015 @07:22PM (#10422544)
An airport security screen is about equivalent to eating 2.5 bananas, don't tell OP that bananas are so scary.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by wavefunction on Tuesday October 20, 2015 @08:38PM (#10422856)
Do bananas do this?

http://www.technologyreview.com/view/416066/how-terahertz-wa...

Tell us more about bananas...

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by jryan49 on Tuesday October 20, 2015 @09:25PM (#10422993)
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by aaronkrolik on Tuesday October 20, 2015 @04:21PM (#10421566)
I fail to see how my post is implying that you should be fine with non-necessary irradiation. I'm quoting and linking the manufacturers website.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by cryoshon on Tuesday October 20, 2015 @04:31PM (#10421618)
The quantities of radiation quoted by the manufacturer are extremely low. The actual effective absorbed dose might be different from what they actually say, of course.

I am anticipating that someone will come forth to defend this illegal searching by claiming that the radiation dose is negligible or irrelevant. I want to counter this defense by posing the matter as philosophical rather than an empirical question of whether the irradiation is harmful or not.

EDIT: Ah, in the time that it took me to write this, I have been proven correct.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by CamperBob2 on Tuesday October 20, 2015 @04:56PM (#10421757)
The quantities of radiation quoted by the manufacturer are extremely low.... when the machines are in proper working order, and maintained and operated as intended by the manufacturer.

My dentist had to take a course in health physics before being allowed to use an X-ray machine on humans. So did my doctor. What makes TSA agents and New York cops so special?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by aaronkrolik on Tuesday October 20, 2015 @04:44PM (#10421684)
Again, i was simply quoting the manufacturer. Adding information to the conversation. You dont have to believe it or agree with it, but it's a side that should be heard rather than downvoted.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @05:48PM (#10422041)
it's only objective in the context of people who understand the magnitude of the numbers being quoted. No data is provided as to alternate sources of radiation. An analogy is made by the manufacturer, but they have incentive to claim that level is as low as possible.

And, without any other information, the specific quotation being presented appears to imply you think it's no big deal (since you didn't offer any interpretation or make a statement relating to your opinion on the matter).

(though to note, I didn't downvote you, I'm just explaining how the information could be seen as "subjective" and not "objective").

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by deet on Tuesday October 20, 2015 @05:57PM (#10422092)
I don't think you should be downvoted, but realize that people might be responding negatively because the citation you provided is exactly the citation that defenders of the vans and backscatter scanners at airports provide to dismiss safety concerns. So, without context around your citation, it might seem that you're trying to provide an opinionated defense of the safety of the vans.

As others have mentioned, there are also issues regarding whether those numbers can really be interpreted to mean that they are relatively safe. The manufacturers of backscatter tech claim that's true, but others suggest that because of the concentration in the skin, it's not a good estimate of safety. To interpret your cited numbers, the discussion also needs that side of the story, which other commenters have provided, but your original post did not.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by bmelton on Tuesday October 20, 2015 @07:53PM (#10422688)
> there are also issues regarding whether those numbers can really be interpreted to mean that they are relatively safe.

And contributing the manufacturer's stated specifications ADDS to that conversation, which meets the criteria for 'goodness'.

Not directing this at you, as you've already acknowledged that the OP should not have been downvoted, but additive facts should, probably as a rule, never be downvoted on account of knee-jerk reactions.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by mikeyouse on Tuesday October 20, 2015 @04:36PM (#10421639)
How's this for a compromise:

Philosophically, the government should not be irradiating people without their consent under any circumstance. Empirically, there is no* health risk from doing so with these vans.

* By any reasonable measure of increased incidence of cancer from small doses of radiation.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @05:50PM (#10422056)
Except there's nothing to support the latter statements. The statement made by the manufacturer 1) could be totally false, 2) refers to a specific single-use of the technology.

They're claiming a specific output per-scan. What if the police are using this van with 10-second scan intervals, pointed at the same building, with people inside, for several hours? That's a fairly plausible scenario which could result in several ORDERS OF MAGNITUDE more irradiation.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:20PM (#10423256)
> That's a fairly plausible scenario which could result in several ORDERS OF MAGNITUDE more irradiation.

"Orders of magnitude" is not a magic phrase you get to throw around to scare people.

Assuming 10 seconds intervals and instantaneous scans going on for 8-12 hours you've gone up just about 3 orders of magnitude. That is, from banana-equivalent dose to about the background radiation dose, per this handy radiation reference[0]. In other words, people in that building receive twice the amount of radiation that they would naturally do.

That is assuming a hell and a lot of scans while also ignoring the protection offered by distance and the building itself.

I refuse to be scared.

[0] - https://xkcd.com/radiation/

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @11:07PM (#10423444)
It wasn't thrown around to scare people, it was used because it's accurate. I fail to see how my statement is inaccurate considering by your own admission there are indeed several (3) orders of magnitude difference.

The point I was trying to make was saying that it's some negligible number is wrong. By your own handy reference, it's the equivalent of 2 Dentist x-rays.

The dentist at least has the decency to put a lead bib over you.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @11:21PM (#10423485)
> I fail to see how my statement is inaccurate considering by your own admission there are indeed several (3) orders of magnitude difference.

"Three orders of magnitude" is a meaningless thing without context, and I just pointed out that in this context it still doesn't change the conclusion that the exposure is neglible and not worth considering.

> The dentist at least has the decency to put a lead bib over you.

That's because people are irrational and you need to dance around them for their own sake.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Tuesday October 20, 2015 @11:39PM (#10423562)
My context:

Person A says 1 does of product A is Amount X.

What I'm saying is: That's not entirely relevant if we don't know how many doses people actually get.

I agree about irrational, among other things.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @11:54PM (#10423607)
> What I'm saying is: That's not entirely relevant if we don't know how many doses people actually get.

True. But then if we count up the reasonable upper bound of possible doses you could get, like "several thousands times a day times amount X", and it still adds up to "not harmful", should we keep being distressed about it?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by rnovak on Wednesday October 21, 2015 @12:08AM (#10423656)
See, I'm totally okay with that explanation then. If the upper bound is insignificant, then I see no reason to worry about the health aspects.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by onnoonno on Wednesday October 21, 2015 @07:04AM (#10424674)
Get your calculation right:

Assuming 100nSv per scan (first comment in this post). 10s per scan. ~4000 scans in 12h.

-> 400uSv = 0.4mSv.

Background where I live: 2mSv per year. So this is a fifth of the yearly background dose at my place. But in a single day.

For example, scan the entrance/exit of a parking garage (such as one under supervision) regularly, and you have a realistic chance of severely harming the guy at the ticket booth.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Wednesday October 21, 2015 @11:41AM (#10426182)
Ok. You're right. I fucked up big.

I skipped an order of magnitude here. Your calculation seems correct, so we're up to about a mamogram / day (still ignoring the distance and shielding effects of the building, but we're computing the reasonable upper bound on exposure).

Over the year this 0.4 mSv adds up to about 146 mSv. Per the Handy Chart, it's between EPA dose limits for emergency workers protecting valuable property and for those in lifesaving operations. It's about 1.5 times the "lowest dose clearly linked to increased cancer risk".

So in the worst reasonable case, this seems to be indeed causing an unnecessary increase of cancer risk. Personally I think the conditions for that upper bound are very extreme so the real dose in actual use would not be nowhere near the amount calculated above, but at this point I have to agree there's a reason to be concerned and demand more information about the deployment and capabilities (especially radiation output in failure modes) of those machines.

In short: most likely still not in any way dangerous, but the revised margins are much slimmer, therefore there is a reason for concern.

I apologize for misleading anyone by accidentally skipping a zero.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by vacri on Wednesday October 21, 2015 @01:16AM (#10423841)
> Philosophically, the government should not be irradiating people without their consent under any circumstance.

So you are against public broadcasting systems? You also don't think that a government should have a moral duty to operate an emergency broadcast system for helping people deal with natural disasters? X-rays and radio waves are both EM radiation.

To be even more pedantic, this stance also means that a government building would not be able to have any lights or heaters (amongst other things). Or a cop searching for a suspect at night wouldn't be able to use a torch.

I think it's a bad, absolutist philosophical point to make.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by ytpete on Wednesday October 21, 2015 @03:56AM (#10424188)
I think the poster was referring only to ionizing radiation (the kind proven to increase cancer risk). Light fixtures and heaters (infrared) don't fall into that category.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by vacri on Wednesday October 21, 2015 @05:52AM (#10424482)
You are correct - I was mostly speaking for effect. But the absolutism is still a problem. For example, if you get into a car accident and are taken to an emergency department in a state where your life is in jeopardy but you are unable to provide consent - should the medical staff have the moral right to do x-rays, which greatly aid their diagnoses?
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by CamperBob2 on Wednesday October 21, 2015 @05:09PM (#10428723)
The medical staff had to take health physics courses and receive state certification before being allowed to use x-ray machines on humans.

The cop took physics in high school and got a 'B'. Oh, wait, no, that wasn't physics, that was physical ed.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by ytpete on Monday October 26, 2015 @10:48PM (#10455958)
Also, the medical staff are irradiating you for the direct purpose of aiding you specifically. The police are irradiating you because they've decided you are by default a suspect worthy of search simply by virtue of passing by - the benefit you receive in return for any health risk is debatable at best.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by coldtea on Tuesday October 20, 2015 @06:23PM (#10422247)
Was it supposed to imply anything? Or it was just an information dump for information's sake, leaving it to the readers to make their own conclusions?

Because regardless of what your post's purpose was, people are obviously gonna read that extract as "hey, it's inside safety limits, so it's ok".

When we post something without further comment it's quite safe to assume that people will think we agree with it, and we're using it to pass a message (especially the most obvious reading it has). The only other interpretation that's (a little less) common, is for people to think we've quoted it sarcastically.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by oh_sigh on Wednesday October 21, 2015 @12:59AM (#10423802)
I suspect you don't actually hold true to this policy of not consenting to "any form of non-necessary irradiation, regardless of the quantity."
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by vacri on Tuesday October 20, 2015 @10:54PM (#10423401)
> I don't consent to any form of non-necessary irradiation, regardless of the quantity.

TV, radio, cell towers...

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by VLM on Tuesday October 20, 2015 @04:48PM (#10421713)
"I don't consent to any form of non-necessary irradiation, regardless of the quantity."

Standing in front of the US capitol building for about an hour is also about 0.1 uSv. Granite is quite radioactive, you know. Some kitchen countertops are much worse.

0.1 uSv is also the generally accepted as the "banana equivalent dose". Bananas are a decent source of potassium, which aside from being an essential element is also somewhat radioactive.

There is no fixed accepted dose rate for flying. More than a couple and less than a dozen uSv/hr is about as accurate as you're gonna get. Depends on flight path and altitude and who knows what all else. The claim that its a couple minutes of flight is not all that far from the truth, more or less.

People who don't really understand what they're afraid of can't rationally minimize risks anyway. Perhaps the granite in a kitchen countertop or architectural decorative feature would increase cancer death rate by 0.0001% but cancer due to chemical catalyst contamination in a replacement laminate countertop MIGHT be ten times the cancer death rate of radioactive granite. Or maybe not.

Assuming they're telling the truth about the dose, I wouldn't worry about the radiation dose. Its small enough to be measured but biologically irrelevant.

What is highly suspicious is a police state violating constitutional amendments probably isn't very concerned with citizen health and probably feels no need to tell the truth. I could see some PR guy claiming its only 1 banana-equivalent-dose or an hour sitting at a granite countertop or whatever because he knows its irrelevant, even if the actual dose is so high that passersby hair is falling out and they're getting radiation burns because its an enormously higher dose. I mean, the government would never lie to us, would they?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by colordrops on Tuesday October 20, 2015 @05:09PM (#10421826)
Your argument is fallacious.

An analogy of your argument: gravity exerts harmless levels of physical force on your body, therefore the government has the right to exert harmless levels of physical force on your body.

By the way, radiation exposure is cumulative throughout your lifetime. There is no safe minimum level of radiation exposure. How much radiation you get on a flight is irrelevant to the topic at hand.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by nitrogen on Tuesday October 20, 2015 @06:47PM (#10422382)
By the way, radiation exposure is cumulative throughout your lifetime. There is no safe minimum level of radiation exposure. How much radiation you get on a flight is irrelevant to the topic at hand.

AIUI the "linear no threshold" model of radiation is widely accepted, but not universally accepted. https://en.wikipedia.org/wiki/Linear_no-threshold_model#Cont...

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:33PM (#10423315)
> By the way, radiation exposure is cumulative throughout your lifetime. There is no safe minimum level of radiation exposure. How much radiation you get on a flight is irrelevant to the topic at hand.

It still doesn't matter; assuming the official values are correct within two orders of magnitude, those scans still get dwarfed by the natural background radiation you are exposed to every day.

Complaining about this, or expecting someone to get consent for such levels of radiation, is ridiculous (yes, there are very important reasons for which one should oppose those scans, but radiation is not one of them). It's just failure of thinking by refusing to do the math. By the same token, why should we allow you to increase risk of heart attack of everyone here by using scary-sounding words like "radiation exposure" in the comments? Stress adds up too.

Please meditate over this handy reference chart: https://xkcd.com/radiation/.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by colordrops on Tuesday October 20, 2015 @10:51PM (#10423391)
I think most of us here are aware of the basic nature of radiation exposure and have also seen this popular XKCD chart. I personally had to learn a lot about radiation exposure due to a bout with thyroid cancer and radiation treatment and scans. But that is not the point. It's not about the dangers of radiation. It's about the right to expose people to radiation at all, regardless of the danger level.

By your reasoning, it would be OK for the police to take a few pennies here and there from large bank accounts.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @11:01PM (#10423422)
> By your reasoning, it would be OK for the police to take a few pennies here and there from large bank accounts.

By my reasoning it's ok for the police to drive around in their cars even though they add up to traffic, which costs a lot of people some pennies lost in gasoline and opportunity cost.

The only reason we're talking about it is because "radiation" sound scary while other things, like "time lost in increased traffic" do not. At the levels of danger we're talking about here we should not be bringing concept of people's rights, lest we want to also regulate disagreeing in Internet comments because of increased heart attack risk from stress.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by YeGoblynQueenne on Thursday October 22, 2015 @08:48PM (#10436180)
> The only reason we're talking about it is because "radiation" sound scary

Radiation doesn't "sound" scary, it is scary. And for very good reason: because at the hands of people who don't understand the dangers, it can be absolutely devastatingly lethal.

Take for instance the irradiation accident in Goiania (Brazil) where a radioactive source was removed from a trashed teletherapy machine by people scavenging for scrap.

This is from the IAEA report on the case:

After the source capsule was ruptured, the remnants of the source assembly were sold for scrap to a junkyard owner. He noticed that the source material glowed blue in the dark. Several persons were fascinated by this and over a period of days friends and relatives came and saw the phenomenon. Fragments of the source the size of rice grains were distributed to several families. Theis proceeded for five days, by which time a number of people were showing gastrointestinal symptoms arising from their exposure to radiation from the source.

(online here: http://www-pub.iaea.org/mtcd/publications/pdf/pub815_web.pdf)

Result, 249 people contaminated, 4 of which died and 28 suffeed radiation burns, plus environmental contamination kilometers away.

That's why people are scared of radiation. Because it can seriously mess you up.

And I fear that going around and saying "it's totally harmless, like eating a banana" is really not helping the people who use it to be really, really careful how they use it. And they should- because if they don't then it's not at all harmless.

Basically, a backscatter van like the ones we discuss here, if left at the hands of people who do not have any training as radiologists (and possibly even then) is, indeed, for all intends and purposes, a chariot of death with an invisible death ray gun.

Tell me what keeps the operators of this sort of van from forgetting the scanner to "ON" pointing at a crowded building and going for a wee, or a coffee, or taking a nap or whatever. People have done much, much more stupid things than that. See above- glow-in-the-dark powder. They thought it was magical fairy dust and daubed it on their babies [edit: actually that was in a very similar accident, in Ciudad Juarez]. 'Nuff said?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by YeGoblynQueenne on Thursday October 22, 2015 @08:30PM (#10436116)
"those scans still get dwarfed by the natural background radiation you are exposed to every day."

As others have said, the effects of radiation are additive, therefore those scans are not "dwarfed" by the natural background radiation etc, they increase it.

Take heat as an analogy. If the background level is at your body temperature and seventy different processes raise it by 1 degree C, you'll boil in your own skin. The background level is safe, each raise is safe, but added up they kill you.

The question is: is this possible with those vans? Is it conceivable that, in some cases, for some people, they may cause a lethal increase in their daily dose of radiation? Is it possible to know this for sure? Uncertain death is even scarier than certain death and for very good reason.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by VLM on Tuesday October 20, 2015 @05:38PM (#10421990)
A far better gravitational analogy, assuming I did the numbers right in my head, when a cop stands a normal distance away from me while talking to me, the gravitational force he exerts on my body is assaulting me with about ten billionths of a newton. Depending on how many donuts he's eaten in his career the force might be higher but it would be in the "dozens of billionths of a newton" for sure. And no means no, and no level of assault is acceptable.

Having a cop stand to either side of me superficially would balance the gravitational force, but unfortunately I'd still be getting violently physically assaulted by tidal forces as my flesh stretches out ever so microscopically toward them both.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by hugh4 on Tuesday October 20, 2015 @05:33PM (#10421966)
The government already entitles itself to do far worse things than bounce a few photons off me now and then -- eg every year they pry open my wallet and entitle themselves to a very large fraction of my income.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by nosuchthing on Tuesday October 20, 2015 @05:46PM (#10422035)
You're free to move to other municipalities without public services, infrastructure, and taxes.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @11:04PM (#10423437)
You should also be wary to chose the new place carefully, there are many areas on Earth where the background radiation is higher than in NY with a scan-van on every corner working constantly.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by dguaraglia on Tuesday October 20, 2015 @05:53PM (#10422073)
So, by that argument, we should just let the government do anything then? I once had a similar argument with a friend who insisted there should be stricter gun laws "because the government already has tanks and planes, so the second amendment doesn't make any sense anymore; they could always bomb the shit out of the public if they wanted."

I think the opposite is truth: we need to act now while we still have some power, rather than assume a defeatist attitude and let our children and their children at the mercy of a fully omnipotent government.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by anon1mous on Tuesday October 20, 2015 @06:13PM (#10422190)
That's a lost battle, the future is dark :(
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by hugh4 on Tuesday October 20, 2015 @06:49PM (#10422389)
No, my actual argument is that all arguments of the form "If the government is allowed to do X then they have to be allowed to do Y, Z and Z' " are a bit silly.
Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by suneilp on Tuesday October 20, 2015 @05:56PM (#10422090)
The problem is that x-rays use ionizing radiation which is more dangerous. Some people could be more sensitive or in a more likely scenario they get a lot of x-rays and/or ct scans due to medical issues which requires them being very careful about spacing out scans and exposure to other sources.

Then there is the possibility someone walks in between the van and target. At some point you have to stop the argument that this and that does x and y so z is ok. People are afraid of excessive radiation and the government isn't listening to people.

One thing that infuriates me is that people making these arguments don't even know that x-rays (and cats) use ionizing radiation which is what carries real risks. Incidentally, MRIs do not use ionizing radiation so you can stay in there a "while". Thats how they can do so many cool studies using MRIs.

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by TeMPOraL on Tuesday October 20, 2015 @10:44PM (#10423358)
The problem is people refuse to do the math, or to listen to people who did the math. All they hear is "that scary r-thing".

At this point I think this link will beat Meditations on Moloch in the "most often posted in comments by this user" statistic, but once again I'm pointing to this helpful chart: https://xkcd.com/radiation/.

> People are afraid of excessive radiation and the government isn't listening to people.

People are afraid of a lot of things, and at this point I'm not sure how we should deal with it on a social level anymore. They are scared of radiation, therefore allow for lots of unnecessary deaths, destruction of the environment and even more radiation by refusing to replace coal plants with nuclear ones. They're also afraid of vaccines, microwaves and cell-phone EM radiation (how they were never afraid of radio waves in pre-cellphone era is beyond me, but maybe they initially were but got over it).

That people are afraid of things that aren't dangerous doesn't mean we should stop doing that things. As for how to make people not afraid, I don't know anymore. Maybe we should just pay the advertising industry to fix that with propaganda?

Re:The NYPD Is Using Mobile X-Ray Vans to Spy on Unknown Tar... by caf on Tuesday October 20, 2015 @07:40PM (#10422630)
Interestingly, due to the altitude it flew at Concorde included a radiation detector that triggered a cockpit warning light when the incident ionizing radiation exceeded a preset limit. The standard operating procedure if the warning was triggered was to descend to a lower altitude.

(Presumably this was more about the aircrew's cumulative dose than the passengers).