Wednesday, March 23, 2011

Monitoring radiation in Kona Hawaii

As soon as we realized that a half dozen nuclear reactor cores were overheating and melting down in Japan, we turned on our 3 radiation detectors  to see if the radiation was going up here in Kona. We have not given our detectors much attention since moving to Hawaii. Unlike the wide variations in readings we would get on the mainland, the detectors have been consistent here day after day with the same low readings. We knew when we moved to Hawaii that there were no local massive nuclear reactors or nuclear weapons factories. And we knew that wind patterns were favorable for low radiation fallout in case of a disaster elsewhere. However, the extent of damage and ongoing radiation contamination at the Fukoshima nuclear power plant is disturbing.

In Hawaii we are 2200 miles closer to the reactors in Japan than the US mainland and if for some reason the wind blew directly this way (fortunately it rarely does) we might get more concentrated nuclear contamination and a higher dose of radiation.   We are happy that our detectors are showing the normal low levels of background radiation (.016 mREM/hour), so far.

We started monitoring radiation over 20 years ago while living in Los Alamos, New Mexico. When measuring radiation dosage, it’s all about the rate of exposure, in other words, how much radiation and for how long. Fortunately our bodies are capable of and used to repairing the damage from background radiation. The problem occurs when the rate of damage from radiation exceeds our body’s ability to repair itself. OSHA uses REMs (Roentgen Equivalent Man) to quantify radiation exposures. Over the years OSHA has come up with the whole body maximum exposure rate of 1.25 REM over any 3 month period and a total maximum exposure of 5 REM per year.

Dosage is also measured by RAD (Roentgen Absorbed Dose), a measure of the actual amount of radiation absorbed. Sieverts have been promoted by the medical industry because it takes into consideration the volume of the portion of the body exposed and the amount of time of exposure. But in a nuclear disaster like the one in Japan, the distinction is less relevant because every part of the body is getting dosed. Even so, Sieverts are being used to report the dosage to the public. One Sievert (Sv) is equal to 100 REM. To add to the confusion, radiation exposure is also being reported in Grays and nanoGrays, yet another measurement of radiation dose

We created a radiation unit converter Google gadget that allows you to enter in any value and see the values of the other dose units so you can compare them.



Here is what we are finding about the radiation exposure in Japan:
  • Reports from an independent radiation monitoring site on the internet is showing 38 microREM per hour in Tokyo.
  • The IAEA Radiation team took measurements at distances from 56 to 200 km from the Fukushima nuclear power plant on March 20 and they found contamination levels that ranged from 2 to 160 microSieverts per hour. The Nuclear and Industrial Safety Agency said on March 23 that the workers at the Fukushima plant had withdrawn after radiation monitoring showed levels of 500 millisieverts per hour.
  • Our readings in Kona Hawaii range between .005 and .020 mREM per hour.

6 comments:

Steve Wasko said...

Thank you for sharing. We are destined for Kona in 3 weeks and appreciate this information being shared.

y said...

Please post more comments about what radiation levels you are seeing!! What are you detecting B-decay (e.g., Iodine 131) isotopes or Gamma decay isotopes?

Unfortunately the only B-radiation detectors in Hawaii were conveniently offline or malfunctioning (makes me sick) see these: This one just came online AFTER the predicted wave of radiation passed the islands (how convenient) http://www.radiationnetwork.com/AlaskaHawaii.htm

And this one refuses to post the B-radiation readings...B radiation is basically the only type of radiation that we should have seen higer levels of, not gamma. Gamma would not be predicted to increase substantially unless there was an explosion related to a core meltdown..so far one core is partially melted down but no explosion. So please post more information we all are relying on you and other members of the public to provide us with honest, unbiased information, which we can't rely upon from the any institutionalized source based upon the convenient failures and delays.

y said...

Forgot to add the second one which the Beta sensor is out of order. Beta radiation is mainly what is expected from this initial Japanese reactor release.

http://www.epa.gov/radiation/rert/radnet-honolulu-bg.html

Please post any other links to useful radiation monitoring sites in Hawaii. There are many good private geiger counters on the mainland (SF, CA).

y said...

Hi again, I did not see any comment posted so I'll reiterate.

All other official websites with radiation monitoring readings are not operating properly. This one did not come online for Hawaii until AFTER the predicted radiation cloud passed us: http://www.radiationnetwork.com/AlaskaHawaii.htm

And this one says the Beta radiation sensor has malfunctioned for the whole duration of the event. http://www.epa.gov/radiation/rert/radnet-honolulu-bg.html

This is frustrating to say the least because Beta decay isotopes (e.g., Iodine 131) are the main forms of radiation from this Japanese Nuclear Reactor event thus far..we would not expect to see Gamma radiation in any appreciable amounds unless one of the cores melted down and exploded. Can you please post your B-decay radiation readings for the whole event? Please keep posting on this because there is no other source of honest, unbiased information on the radiation situation in Hawaii. Thank you very much!!!

HiloLiving said...

Thanks for the information and questions Y. We agree that it is a concern when key instruments are not working and it does not promote public confidence.
Our detectors are very simple, they do a count per minute for total alpha, beta, and gamma radiation. We do not have a gamma spectrometer to tell which isotopes are causing the counts.
Fortunately our detectors are all showing low levels consistent with the same background levels we have seen for year. In the past on the mainland, we found these simple detectors very sensitive to releases of all types as well as contamination on the ground.
We will continue to measure the radiation levels in Kona and write about what we see. Thanks again for your interest and comments.

Kristina Laura said...

I truly like to reading your post. Thank you so much for taking the time to share such a nice information.
Geiger Counter