Posted on September 27th, 2009 257 comments
Chronic radiation is defined as the radiation received slowly or in a low-dose-rate from various sources. It is completely different in nature to the acute gamma or neutron radiation generated from the atomic bomb explosions that occurred in Japan at the end of World War II. Tantalizing insights from people living in higher-than-normal background radiation areas in the world and from nuclear energy workers receiving excess radiation over long years have suggested that chronic radiation might paradoxically be beneficial to humans. However, in the absence of an epidemiological study, it has been impossible to conclude whether chronic radiation is harmless or indeed beneficial to human beings. Fortuitously, an incredible Co-60 contamination incident occurred in Taiwan 21 years ago, which provided the data necessary to demonstrate that chronic radiation is beneficial to human beings.
The contamination occurred during the recycling of metal scrap when a Co-60 source was mixed with metal scrap, melted and drawn into steel bars in the mill. Unaware of the contamination, the steel bars were ultimately used in construction of more than 180 buildings in 1982-84. Most buildings were partitioned into about 1,700 apartments for dwelling, and some buildings for other purpose. The first contaminated apartment was discovered in 1992. The residents in the apartments totaled 10,000 individuals who had been exposed to chronic radiation for at least 9 years and as long as 21 years.
The beneficial health effects of radiation observed in the Taiwan Co-60 contamination incident are so unique, they could also coincidentally explain the theory developed by Dr. T.D. Luckey, and his Complete Dose-Response Curve as shown in the last page of his book, “Radiation Hormesis 1991.” The dose of chronic radiation of about 100 mSv/y is optimum to health with up to 10 Sv/y still being in the hormetic range. Dr. Luckey predicted in his paper at the 1999 American Nuclear Society annual meeting in Boston that if the American population received a supplemental radiation dose through the public health service of about 55 mSv, 49 % of the cancer deaths of the US population (about 200,000 Americans) could be prevented every year. Of course, many people were shocked by his suggestion. However, findings from this study suggest the potential of radioactive vaccines to prevent cancers.Uncategorized Atomic Bomb Explosions, Background radiation, Contamination Incident, Dose Response Curve, Effects Of Radiation, Energy Workers, Epidemiological Study, Excess Radiation, Gamma Radiation, Health Effects Of Radiation, low level radiation, Luckey, Metal Scrap, Msv, Neutron Radiation, Nuclear Energy, Radiation Areas, Radiation Hormesis, Socie, Steel Bars, World War Ii Top
Posted on June 3rd, 2009 219 comments
This counter is nice and is made in the USA, is pretty sensitive and comes calibrated, I did pay about $480 for it and it is one of the best ones out there. Here are key features -
The Radalert 100 is a general purpose geiger counter that measures alpha, beta, gamma, and x-radiation. Exciting new features of the Radalert 100 — as an upgraded version of the popular Radalert 50 — include a three-second update and a utility menu that allows you to change the default settings for several operating parameters. Its digital liquid crystal display (LCD) shows the current radiation level in your choice of milliroentgens per hour from .001 to 110 or counts per minute (cpm) from 0 to 350,000. When SI units are selected, the LCD shows readings in microsieverts per hour from .01 to 1100 or counts per second (cps) from 0 to 3,500. This instrument also offers an accumulated total and timer function, up to 9,999,000 counts and 40 hours. A red LED blinks and a beeper chirps with each count (the chirp can be muted). An audible alert sounds when the radiation reaches a user-adjustable level. The Radalert 100 meets CE certification requirements for Europe.
• Halogen-quenched Geiger-Meuller detector (LND712)
• Mica end window density is 1.5-2.0 mg/cm²
• Side wall is 0.012″ #446 stainless steel
• Detects Alpha, Beta, Gamma, and X-radiation
Display: 4-digit liquid crystal display with mode indicators
Operating range: mR/hr: .001-110 CPM: 0-350,000 µSv/hr: .01-1,100 CPS: 0-3,500 Total: 0-9,999,000 counts Timer: up to 40 hours
Calibration: Cesium 137 (gamma)
Sensitivity: 1000 cpm/mR/hr referenced to Cs-137
Accuracy: ±10% typical; ±15% max. (mR/hr & mSv/hr modes)
Alert: User-adjustable alert level to 50 mR/hr & 160,000 CPM
Count light: Red LED flashes with each count
Audio: Beeper chirps for each count (can be muted)
• Output: Stereo 3.5 mm jack sends counts to computers, data loggers, other CMOS-compatible devices, and headphones
• Input: Mono 2.5 mm jack provides electronic calibration input
Power: One 9-volt alkaline battery; average battery life is 2160 hours at normal background, 625 hours at 1 mR/hr with beeper off
Size: 150 x 80 x 30 mm (5.9″ x 3.2″ x 1.2″)
Weight: 225 grams (8 oz) including battery
Options: Computer cable and software (IBM PC compatible)
CE CertifiedBasics Alpha Beta Gamma, Cesium 137, Chirp, Chirps, Compatible Devices, Cs 137, Data Loggers, Display Lcd, Gamma Radiation, Gamma Sensitivity, Geiger Counter, Led Flashes, Liquid Crystal Display, low level radiation, Meuller, Radalert, Radiation Level, Stereo 3, Timer Function, Utility Menu, X Radiation Top
Posted on June 1st, 2009 2 comments
Ionizing radiation is radiation that changes the structure of individual atoms by ionizing them. The ions produced in turn ionize more atoms. Substances that produce ionizing radiation are called radioactive.
Radioactivity is a natural phenomenon. Nuclear reactions take place continuously on the sun and all other stars. The emitted radiation travels through space, and a small fraction reaches the earth. Natural sources of ionizing radiation also exist in the ground. The most common of these are uranium and its decay products.
Ionizing radiation is categorized into four types:
X-rays are usually man made radiation produced by bombarding a metallic target with electrons at a high speed in a vacuum. Xrays are electromagnetic radiation of the same nature as light waves and radio waves, but at extremely short wavelength, less than 0.1 billionth of a centimeter. They are also called photons. The energy of x-rays is millions of times greater than that of light and radio waves. Because of this high energy level, x-rays penetrate a variety of materials, including body tissue.
Gamma rays occur in nature and are almost identical to x-rays, but generally have a shorter wavelength than x-rays. Gamma rays are very penetrating.
Beta radiation. A beta particle consists of an electron emitted from an atom. Beta particles penetrate matter less deeply than gamma or x-rays, but they are biologically significant because they can be more effective than gamma radiation at disrupting cellular material.
Alpha radiation. An alpha particle consists of two protons and two neutrons, the same as the nucleus of a helium atom. It generally can travel no more than 1 to 3 inches in air before stopping, and can be stopped by a piece of paper.
When an atom emits an alpha or beta particle or a gamma ray, it becomes a different type of atom. Radioactive substances may go through several stages of decay before they change into a stable, or non-radioactive form.
An element may have several forms, or isotopes. A radioactive form of an element is called a radioisotope or radionuclide. Each radionuclide has a half-life, which is the time required for half of a quantity of the material to decay.
The following chart shows the complete decay chain for uranium 238, which ends with a stable isotope of lead. Notice that the half- life of the radionuclides in the chain range from 164 microseconds to 4.5 billion years.Nuclear, Research Alpha Particle, Alpha Radiation, Beta Particle, Beta Particles, Beta Radiation, Cellular Material, Decay Products, Electromagnetic Radiation, Gamma Radiation, Gamma Ray, Gamma Rays, Helium Atom, Level X, Light Waves, Natural Phenomenon, Radio Waves, Radioactive Substances, Sources Of Ionizing Radiation, Understanding Radiation, X Rays Top