Another NORM issue relates to radon exposure in homes, particularly those built on granitic ground. Occupational health issues include the exposure of flight crew to higher levels of cosmic radiation, the exposure of tour guides to radon in caves, exposure of miners to radon underground, and exposure of workers in the oil & gas and mineral sands industries to elevated radiation levels in the materials they handle. NORM sources Gooding, T.D.; Smith, K. R.; Sear, L.K. 2006, A radiological study of pulverised fuel ash (PFA) from UK coal-fired power stations, joint paper by the Health Protection Agency and the United Kingdom Quality Ash Association (UKQAA) presented at the UKQAA's Ash Technology Conference 2006 (AshTech 2006) held in Birmingham, UK on 15-17 May 2006 Granite, widely used as a cladding on city buildings and also architecturally in homes, contains an average of 3 ppm (40 Bq/kg) uranium and 17 ppm (70 Bq/kg) thorium. Radiation measurements on granite surfaces can show levels similar to those from low-grade uranium mine tailings. Table 8 shows some recorded activity concentrations for building materials. However some extreme values in excess of these have also been recorded. NORM results from activities such as burning coal, making and using fertilisers, oil and gas production.

Typically exposure to radon and its progeny accounts for half of an individual’s radiation dose, making it the single largest contributor. This radon comes from the ground, with exposure affected by factors such as local geography, building construction, and lifestyle. Radon levels in the air range from about 4 to 20 Bq/m 3. Indoor radon levels have attracted a lot of interest since the 1970s and in USA they average about 55 Bq/m 3, with an EPA action level of 150 Bq/m3. Levels in Scandinavian homes are about double the US average, and those in Australian homes average one fifth of those in USA. Levels up to 100,000 Bq/m 3 have been measured in US homes. In caves open to the public, levels of up to 25,000 Bq/m 3 have been measured.A Japanese study on 3000 residents living in an area with 60 Bq/m 3 radon near Misasa hot springs showed no health difference. The ICRP recommends keeping workplace radon levels below 300 Bq/m 3, equivalent to about 10 mSv/yr. Norm wakes up with his dog on his face. His brother tells him to come down, because his parents want to speak to him. Cut to Norm lamenting on the woes of having siblings and reminiscing about the days of being an only child, and getting a shed-load of attention. His parents say they're going to a loathable shop, but he must stay in to wait on a parcel. They leave. He makes a deal with annoying neighbour Chelsea to have her wait on the parcel. Now time to do the awesome thing that is biking with best friend Mikey. Stupid name. Sorry. Crashes his bike. Finds Mikey isn't in and just bought a new bike for no good reason. Strikes off friendship for petty reason. Finds the parcel is an okay phone for him. Gets his grandfather to mend the bike. All is well.The EU encourages the use of NORM residues in building materials, subject to dose rate from gamma exposure being below 1 mSv/yr from them. Coal ash and smelting slag are an important constituent of building materials in China. Recycling and NORM

Decommissioning experts are increasingly concerned about double standards developing in Europe which allow 30 times the dose rate from non-nuclear recycled materials than from those out of the nuclear industry. In respect to actual dose limits, 0.3 to 1.0 mSv/yr individual dose constraint is applied to oil and gas recyclables, and 0.01 mSv/yr for release of materials with the same kind of radiation from the nuclear industry. International Atomic Energy Agency, Naturally Occurring Radioactive Material (NORM VII): Proceedings of an International Symposium Beijing, China, 22-26 April 2013, STI/PUB/1664, ISBN 9789201040145 (January 2015) International Atomic Energy Agency, Extent of Environmental Contamination by Naturally Occurring Radioactive Material (NORM) and Technological Options for Mitigation, Technical Reports Series No. 419, STI/DOC/010/419, ISBN: 9201125038 (December 2003)Phosphoric acid is an intermediate step in almost all phosphate applications. Production requires first the beneficiation of the ore, followed by acid leaching and separation. In general the beneficiation stage does not result in a reduction of NORM in the ore.

Terrestrial NORM consists of radioactive material that comes out of the Earth’s crust and mantle, and where human activity results in increased radiological exposure. The materials may be original (such as uranium and thorium) or decay products thereof, forming part of characteristic decay chain series, or potassium-40. The two most important chains providing nuclides of significance in NORM are the thorium series and the uranium series: Though not normally considered as NORM, wastes from the front end of the nuclear fuel cycle through to fuel fabrication may be treated as NORM, opening up more options for disposal. Such material includes uranium oxides. Radon exposure is also an issue in uranium mines. Phosphates and fertilizer production One afternoon, the boys are riding their bikes outside Norm's house. By accident, Mikey crashes into Norm's garage and smashes a valuable china tea set. Unfortunately, Norm's teenage neighbour, Chelsea, films the whole thing and posts the video on YouTube! This means war and Norm's determined to get his revenge...Treatment with sulfuric acid leads to the production of gypsum (phosphogypsum) which retains about 80% of Ra-226 and 30% of Th-232 and 14% of U-238. This means that uranium and thorium are enhanced to about 150% of the value of the beneficiated ore, making it a significant NORM. This gypsum can either be sold or disposed of. In the USA, the use of phosphogypsum with a radioactivity greater than 370 Bq/kg is banned by the Environmental Protection Authority. Gypsum can either be disposed of in piles or discharged to rivers and the sea. Some leaching from the material is possible. Gypsum wastes can have radioactivity levels up to 1700 Bq/kg. Scales from the sulfuric acid process are formed in the pipes and filtration systems of plants and need to be cleaned or replaced periodically. While much smaller in volume than gypsum, these wastes can be much more radioactive – even over 1MBq/kg. NORM in the oil and gas industry poses a problem to workers particularly during maintenance, waste transport and processing, and decommissioning. In particular Pb-210 deposits and films, as a beta emitter, is only a concern when pipe internals become exposed. External exposure due to NORM in the oil and gas industry are generally low enough not to require protective measures to ensure that workers stay beneath their annual dose limits (such as set out by the IAEA basic safety standards). Internal exposures can be minimized by hygiene practices. Metals and smelting Radioactive materials which occur naturally and where human activities increase the exposure of people to ionising radiation are known by the acronym 'NORM'. The amounts of radionuclides involved are noteworthy. US, Australian, Indian and UK coals contain up to about 4 ppm uranium, those in Germany up to 13 ppm, and those from Brazil and China range up to 20 ppm uranium. Thorium concentrations are often about three times those of uranium.