Okay, at the beginning of the episode when Daniel is rushing in after having been exposed, Carter says his hand was exposed to 7 somethings of radiation and his body to about 6. I tried a couple of times but never could quite make out the word, but I didn't recognize it as any sort of radiation dosage I'd heard of. Did they make up a word or did I just not understand/recognize it correctly?

Also, did anyone else find Daniel's actions in this episode reminescent of the guy that died from radiation during the manhattan project when they were working on the bomb and the two halves of plutonium came together and went critical?

Semi correctly. The word was Grays, which isn't strictly what should be used for biological dosage but it is a unit of exposure.

Okay, that's kinda what I thought she'd said, but I never heard of radiation measured like that. I was trying to figure out what the Asgard had to do with radiaton dosage. So, um, what is a gray other than an alien that looks suspiciously like the Asgard.

1 Gray is the amount of radiation required to deposit 1 Joule in 1 kilogram of some substance.

Truth is, I'm not entirely sure exactly how it is defined and how it differs from the Sievert, which is the unit of biological dosage.

Did manage to find this with some further looking:

gray (Gy): Unit of absorbed dose due to any type of radiation. An exposure to 1 gray results from radiation depositing one joule per kilogram of animal tissue or any other material.

sievert (Sv): A measure of dose (technically, dose equivalent) deposited in body tissue, averaged over the body. Such a dose would be caused by an exposure imparted by ionizing x or gamma radiation undergoing an energy loss of 1 joule per kilogram of body tissue (l gray). One sievert is equivalent to 100 mrem or 0.1 rem.

So if I'm reading that right, they basically ARE more or less the same thing.

http://users.rcn.com/jkimball.ma.ult...Radiation.html

It looks like the rad was replaced by the gray and the rem by the sievert. The difference between the two, at least according to this, is that the gray is the absolute exposure and the sievert takes into account the "quality" of the radiation, basically how well it deposits it's energy into the body.

I guess the gray probably WASN'T a good unit to use since if the radiation was xrays or gamma rays it would be 6-7 sieverts, but if it were, say, neutron radiation he would have gotten a dose of 30-35 sieverts and if it were alpha radiation it would have been more like 120-140 sieverts.

I think. I'm guessing that if it were alpha or neutron radiation, though, he would have had a lot more severe burns and would have dropped dead more or less on the spot.

So are we lead to believe that Daniel Jackson died because of exposure to 6-7 rems? I thought you needed much more for a fatal dose. Wasn't this the ep where he died or ascended, or am I mistaken?

__________________
"Oh no no no I'm a rocket man Rocket man burning out his fuse up here alone." -- Sir Elton John

J Pax

Yep. Pierre's favorite episode: LINK :P

What is considered to be a lethal dose is anything beyond 3Sv within the space of a few hours.

Try 6-7 HUNDRED rems. The gray/sievert are 100 rads/rems.

Actually, the full body exposure was over 7Gy of neutron radiation, which translates into over 35Sv. That is bloody lethal. Daniel should have been more careful.

Did they say it was neutron radiation? Honestly, with that kind of exposure, I would have expected that he would have died a lot quicker than 48 hours.

Look at it on the other hand, though. Sure you can say he should have been more careful, but even the guys in their rad suits got lethal doses and died faster than he did (maybe because our medicine is more advanced they were able to buy him a few more hours, or maybe just because they were in there about twice as long). But what if Daniel HADN'T done that? I seriously doubt that he would have had time to make it to the stargate and escape and it would have been a BIG bang I'm betting.

Ok, I thought someone said 1 gray = 1 RAD, or approx 1 REM. However I did check google calculator and is says 6 grays = 600 rem. I thought there was a multiplier in there, but haven't been messing with radiation for a few weeks and I almost always refer to RAD/REM in my studies.

__________________
"Oh no no no I'm a rocket man Rocket man burning out his fuse up here alone." -- Sir Elton John

J Pax

Oma kept him alive.

No, that's never said, and I seriously doubt it. Oma would have stepped into his mind sooner, but I'm fairly sure either 1) he simply had a lesser dose than the scientists, since he was behind the glass from the initial burst, or 2) his own near-ascendant status helped him hang on longer than normal.

I didn't think that it was, but glom watches this a lot more than I do, so I was thinking that maybe I'd missed it and was pondering further.

Perhaps it was a combination of things; lesser dose (though since the other guys were in rad suits presumably, I somewhat doubt that it was much less and they did say it was going right through the glass), biochemical makeup (perhaps we're slightly more resistant), perhaps they had also been getting exposure previously that added to the dose received in the accident. I really DO think that our modern medicine might have help to prolong his life at least somewhat. Look how much our medicine has advanced since the 40's. Symptoms that might have killed him sooner (maybe the seizure for instance) were controlled. Also don't forget Carter's attempt at healling. Even though he had a seizure afterwards, perhaps it helped slightly.

Yeah, the common answer here is that the SGC has had extensive contact with advanced alien cultures, so they should have some advanced "space medicine" going on. Quite likely that they had more advanced forms of radiation burn control than is normal.

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But he that sows lies in the end shall not lack of a harvest, and soon he may rest from toil indeed while others reap and sow in his stead. -J.R.R. Tolkien, The Silmarillion