According to Dr Hammond and his colleagues, a series of studies conducted by BAT's researchers between 1972 and 1994 quantified much of this. The standardised way of analysing cigarette smoke, as *laid down[4] by the International Organisation for Standardisation (ISO), which regulates everything from computer code to greenhouse gases, uses a machine to make 35-millilitre puffs, drawn for two seconds once a minute. The firm's researchers, by contrast, found that real smokers draw 50-70ml per puff, and do so twice a minute. （4）Dr Hammonds's conclusion is drawn from the huge body of documents disgorged by the tobacco industry as part of various legal settlements that have taken place in the past few years, mainly as a result of disputes with the authorities in the United States.

据哈蒙德医生及其同事们称，英美烟草公司的研究员已于1972年到1994年间通过一系列研究对上述大部分问题进行了定量检测。卷烟烟尘分析的标准方法，是由国际标准化组织（ISO，该组织可对包括计算机代码和温室气体在内的所有问题作出规定）制定的，此法利用一台机器喷发出35毫升的烟雾，受试者每分钟吸一次、每次持续2秒即可吸完。以此为对照，英美公司研究员发现，真正的烟民每分钟2次即可吸完50至70毫升烟雾。哈蒙德医生是从烟草业提供的大量文献中得出这一结论的。过去几年烟草业与美国当局一直僵持不下，遂签署了各类法律协议。作为其中的一项内容，烟草业被迫拱手交出这些文献。