The case of the radioactive lift buttons
A French lift-maker scrambled on Wednesday to remove buttons from hundreds of lifts after the nuclear safety authority said Indian-imported materials used in them were radioactive.
Otis planned to remove the buttons from “500 to 600 lifts out of the 2 500 that Otis has installed, modernised or repaired between August 21 and October 9 even if there is no danger for users”, said a company spokesperson.
The firm, a French subsidiary of the United States group of the same name, also said it had isolated thousands of contaminated buttons in three production sites and would destroy them under the control of the country’s nuclear waste authority.
Employees of the sites were asked not to come to work on October 10, after the Nuclear Safety Authority (ASN) told Otis there were traces of radioactive cobalt-60 in Indian-made buttons it had received, the company said.
Otis’s announcements came after the ASN said on Tuesday that 20 French workers who had handled buttons used in lifts had been exposed to excessive levels of radiation.
The authority classed the incident at a factory of the Mafelec firm in the east-central town of Chimilin at level two on the seven-level International Nuclear Event Scale.
It said that of 30 workers exposed, 20 had been exposed to doses of between one mSv (milli-Sievert) and three mSv. The maximum permitted dose for workers in the non-nuclear sector is one mSv, said the ASN.
But France’s institute of radioprotection (IRSN) said the health risk for the Mafelec workers was “extremely low”.
The incident in the factory belonging to Mafelec, which delivers the buttons to Otis, happened in early October, said the ASN.
The Mafelec workers were using materials that came from an Indian supplier, it said.
Faint traces of cobalt-60, a radioactive form of the metal cobalt, were found in the buttons.
The ASN said it believed that several Indian companies had exported products contaminated with cobalt-60 to a number of countries.
It named them as Bunts, Laxmi, SKM Steels, Vipras Castings and Pradeep Metals, and said it was in contact with Indian authorities “in order to find out the result of inspections being carried out on these sites”.
Officials here said the radioactivity in the buttons was probably due to the fact that the metals used to make them were from contaminated recycled materials.
Swedish officials, meanwhile, said on Monday that steel items imported from India showing faint traces of radioactivity had been found in Sweden.
The levels of cobalt-60 in the steel were considered harmless and the steel components have not been recalled, the Swedish Radiation Safety Authority (SSM) said.
“Dutch customs discovered that a shipment of industrial flanges from India to Sweden showed traces of cobalt-60,” a spokesperson said.
That find led to the discovery that a similar shipment had been sent several weeks earlier from India and delivered to three companies at four sites in Sweden.
SSM had contacted France over the Swedish discovery. “It seemed important to contact France to inform them of the contaminated steel flanges which also came from India,” the spokeperson said.—Sapa-AFP