Phase-out of incandescent light bulbs were no longer available from European sources. Russia is phasing out incandescent light bulbs. The production of lamps of 100 watt and more is banned. There are also discussions to ban light bulbs of 50 watts and more. Switzerland banned the sale of all light bulbs of the Energy Efficiency Class F and G, which affects a few types of incandescent light bulbs. Most normal light bulbs are of Energy Efficiency Class E, and the Swiss regulation has exceptions for various kinds of special-purpose and decorative bulbs. In line with EU rules, Switzerland banned the import and manufacture of halogen
Incandescent light bulb Mexico, Cuba, Argentina and Brazil, have prohibited them already. In addressing the question of who invented the incandescent lamp, historians Robert Friedel and Paul Israel list 22 inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. They conclude that Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve (by use of the Sprengel pump) and a high resistance that made power distribution from a centralized source economically viable. Historian Thomas Hughes has attributed Edison's success to his development of