Cobalt 60 for sale8/7/2023 ![]() For the calculations, it was assumed that the occupant spent 6,000 hours per year in the home. It was assumed that for a given nuclide, each of the five tubes contained the activity presented in the previous table. NUREG-1717 estimated the doses to an occupant in a home from five electron tubes that contained either, H-3, Co-60, Kr-85, Cs-137, or Pm-147. NUREG-1717 provided the following NRC data regarding the annual distribution of electron tubes containing byproduct material during the period of 1970 to 1986. This preheating of the lamp improves its ability to conduct. The starter is actually a switch that applies the high voltage to the fluorescent lamp after that latter has been given time to warm up. Today, most fluorescent lamp starters use about 5 pCi of Th-232 coated on the inside of a glass tube. The sources generally consisted of 1 to 9 uCi of Co-60, Ni-63, Kr-85, Pm-147, or Th-232. The report (1987) claimed that the annual production of these devices was in the millions. 95, these devices have been used as starters for compact fluorescent lamps, and in electric blanket thermostats and other specialty products. ![]() NUREG-1775 indicated that several hundred million were produced during the 1970s. Typical activities would be about 20 uCi of H-3, or 0.2 uCi of Kr-85. They are often about 25 mm long and 2.5 mm in diameter. These devices have provided light in many different types of electronic devices including cloths washers and dryers, stereos, coffeemakers, and pinball machines. Most of the voltage regulators and surge arrestors manufactured today are small ceramic cylinders with a thin deposit of Ni-63 on one electrode. These types of tubes have usually contained less than 1 uCi of Cs-137, Ni-63, Kr-85, or Pb-210. Solid state equipment is particularly susceptible to these transients when it is operating off of AC lines. These tubes act as a protection against sudden changes (transients) in high voltage. These tubes generally employed Co-60, Ra-226 or H-3. Anti transmit-receive disconnect the transmitter from the antenna during reception. Their purpose was to disconnect the receiver from the antenna during transmission. Their first use seems to have been in the early 1940s when they began to be used as transmit-receive (TR) tubes in radar systems. These types bear a red three-bladed propeller-shaped symbol." This produces a steadier tube performance.Īccording to the data sheets for the 346B and 346C tubes (provided by jay Damkoehler), they are "for use in relay, voltage regulator, or rectifier circuits" and are "especially suitable for use in control circuits such as triggering, counting, or switching apparatus." Regarding the 346B tube "a few types contain a larger quantity of radium bromide in which the radium approximates that found in a luminous dial watch. The tubes are painted to eliminate the random ionizing events in the tube gas that would occur if light got inside. The solid black tube is a Western Electric 346C tube that contains Kr-85. In the photo to the right, the tube with the hand-painted red trefoil is a Western Electric 346B tube that contains radium. The radioactive source therefore speeds up the operation of the tube and ensures that the tube output is steady and not subject to random fluctuations. In the absence of such a source, the initiation of the current would some random event (e.g., light, cosmic ray, background gamma ray) to ionize the gas. The purpose of the radioactive source is to ionize the fill gas so that the application of a high voltage across the tube results in an instantaneous current. If H-3 or Kr-85 is used, it is typically mixed with the fill gas. ![]() The various radioactive sources that have been used in these devices include H-3, C-14, Co-60, Ni-63, Kr-85, Cs-137, Pm-147, Pb-210, Ra-226, and Th-232. ![]() In general, such tubes consist of a glass envelope, a fill gas, a radioactive source, an anode and an unheated (cold) cathode. ![]() A wide variety of electron tubes have used radioactive material: voltage regulators, spark-gap tubes, voltage sensitive switching tubes, glow lamps, etc. ![]()
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