[3] However, the EF Scale, having been designed based on construction practices in the United States, is not necessarily applicable across all regions.
[4][5] The EF-scale and variants thereof are officially used by the United States, Canada,[6][7] France,[8] and Japan,[9] as well as unofficially in other countries, such as China.
The scale was written in the early 1970s, and does not take into account changes such as the growth in weight of vehicles or the great reduction in numbers and change of type of railway locomotives,[citation needed] and was written in an environment where tornadoes of F2 or stronger are extremely rare, so little or no first-hand investigation of actual damage at the upper end of the scale was possible.
Weather radar is used when available, and sometimes photogrammetry or videogrammetry estimates wind speed by measuring tracers in the vortex.
In most cases, aerial and ground damage surveys of structures and vegetation are utilised, sometimes with engineering analysis.
Guttering pulled from some houses with some siding damage possible, older single glazed windows blown in or out of frames or smashed.
In terms of man made objects, only the very heaviest ones for example locomotives/trains weighing hundreds of tons and the strongest of buildings made low to the ground with specific very aerodynamic designs and incredibly thick load bearing steel concrete walls with no windows/discernible roof will "survive" a tornado of this strength, survival would be reliant on these specialised structures or out of path of the tornado itself.
But the precise design needed and possibility of it actually successfully providing adequate safety during such a tornado is very speculative for now.