перевод 8 breaks out of 1000.

[emiama]

The breakage strength in window design may be specified as a function of the number of windows expected to break at that load. For instance, in conventional design, it is typical to use a breakage pressure corresponding to 8 breaks out of 1000. Where we are certain of a lot of glass breakage, a pressure corresponding to 750 breaks out of 1000 is used to have increased confidence that the frame does not fail too

люди, помогите понять и правильно перевести.

[alk]

http://www.fema.gov/txt/plan/prevent/rms/427/fema427_ch6.txt
...
To make sure that the components supporting the glass are stronger than the glass
itself, specify a window breakage strength that is high compared to what is used in
conventional design. The breakage strength in window design may be specified as a
function of the number of windows expected to break at that load. For instance, in
conventional design, it is typical to use a breakage pressure corresponding to eight
breaks out of 1000. When a lot of glass breakage is expected, such as for an explosive incident, use a pressure corresponding to 750 breaks out of 1000 to increase confidence that the frame does not fail, too. Glass breakage strength values may be obtained from window manufacturers.

имхо:
В обычных конструкциях типичное соотношение для разбитых давлением при установке окон - восемь на тысячу.
Но дальше не очень ясно.