Machine design (flange coupling design) a simple question

[ubnt]

TL;DR

Our teacher finned me 30 point for assuming a safety factor2.5for flange design, is it ok to assume a safety factor?

Our source book is shiegly if someone answer i hope he give me yhe source of his infortmation

 

[Baluncore]

Welcome to PF.

The safety factor may increase with the cost of a failure.
Are there code or design tables available, where ?

I assume 'shiegly' is;
Shigley's. Mechanical Engineering Design. 10th Edition. 2015.
By Richard G. Budynas and J. Keith Nisbett.

Do you refer to a flange for a pipe junction, a drive shaft coupling, RSJ, or something else ?
What part of the text covers the subject.

 

[Nik_2213]

Is there a shock / impulse / snatch factor to consider ??