There is tension in the air over New York - and the rich and paranoid have taken to measuring it on Geiger counters. The click-click-click of a modern, palm-sized monitor that detects radioactivity has become de rigueur in Manhattan, where fear of terror attacks, coupled with the location nearby of a nuclear power plant, have whipped the city into a state of permanent fear. The New York Times was not exaggerating when it called Geiger counters the new Cipro - the anti-anthrax drug. Sales of even the most expensive models have doubled since nuclear fear gripped New York, much as sales of the drug soared following last year's anthrax terror attacks. Web sites like Geigercounters.com say they are doing a brisk trade in all manner of detectors, from US$200 (HK$1,560) units to PC-based ultra-sensitive US$1,000 models. Paranoia peaked last month when US Attorney-General John Ashcroft announced that former Chicago street gang member and recent Islamic convert Abdullah al-Mujahir had been arrested for threatening to detonate a so-called dirty bomb in the country. His admission that he had been in contact with Osama bin Laden's al-Qaeda network only deepened concern and sparked a nationwide scare that a nuclear attack could come at any time. Despite assurances from US experts and editorials in the likes of Time magazine telling readers that the likelihood of such an attack succeeding was very low, panic spread. Matters were not helped by an ongoing campaign to have the Indian Point nuclear power station, less than 80km north of Manhattan, shut down. Protesters have been distributing literature warning of an imminent Three Mile Island-type reactor meltdown for years. But when state government health officials announced in June that they would hand out potassium iodine radiation-sickness pills to residents within its evacuation zone 'just in case', it gave an official veneer to what had hitherto been grumblings from environmental anarchists. On top of that, the threat of war between Pakistan and India heightened panic levels. Ordinarily, tension between the two nations would have passed by most Americans without mention. But after September 11, anyone with a nuclear bomb is now considered a danger. But is it just a fad or will Geiger counters be of any use in the event of an attack or a reactor meltdown? After all, the sudden run on gas masks after September 11 slowed once it was explained that they would not prevent anthrax particles entering the lungs. According to Tim Flanegin, the owner of Geigercounters.com, his products are unlikely to save many lives. 'In the event of a proper nuclear attack, no, nothing will help you,' he said. 'But they will be more useful in the event of the detonation of a dirty bomb.' Even then, the Geiger counter will only act as a warning, he said - and you would have to be close to the detonation to trigger its sensors, by which time your chances of survival will rest greatly on your ability to run. Sales of Geiger counters from Mr Flanegin's site have doubled in the past month, he said, most of them going to New York.