打电话,并持有对话,从事一部分注意用户从其他正在进行的任务中分散注意力的一部分。因此,人的反应性降低。使用免提与否,事故风险可能会增加。谁指出,使用移动设备时,交通事故的风险乘以3或4(驾驶员是否使用的是使用“免提”套件)。A study by the U.S. administration for highway safety, the National Highway Traffic Safety Administration (NHTSA), noted as the United States in 2005, at a given time, about 6% of drivers use a phone held in hand while driving (or 974,000 vehicles at any given time). Only 0.7% of drivers were calling with a headset / microphone remote, and only 0.2% of drivers were dialing a number (Davie, Panting & Charlton, pp.359-373, 2004).