Scale may be in terms of the absolute volume of a single operation or the frequent repetition of a process, because both could give rise to an increased possibility of exposure if the containment and control measures failed and thus affect the possibility of a harmful event occurring.
Obseg je lahko izražen v absolutnem volumnu enega samega delovnega postopka ali v pogostem ponavljanju procesa, saj lahko pri neučinkovitosti zadrževalnih in nadzornih ukrepov oboje vodi do povečane verjetnosti izpostavljenosti in s tem vpliva na verjetnost pojava škodljivega dogodka.