[Lingo] Usage of "should"

[Nguyễn Vũ Hưng <vuhung16plus@example.com>]

Hello all,

In the sentence:
"Contingent response: the actions to be taken should the risk event
actually occur"

I need some help:

1. What is the meaning of "should",
2. I thought that in this case, "should" can be replace by "when", and,
3. Usage of "should" like this are common at the front desk of hotels
:), not technical English :)

-- 
Best Regards,
Nguyen Hung Vu [aka: NVH] ( in Vietnamese: Nguyễn Vũ Hưng )
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