PWHT Requirements As Per UCS-56-1 General Notes b (1) & (2) 1

[SmallInfo]

Hi Experts
I'm a bit confused about the differences between these highlighted points. Can you please help me understand them better?
Thanks in Advance

 

[Maslov]

If the nominal thickness exceeds 1-1/4" you must preheat your welds, or else you have to do PWHT.

If the nominal thickness exceeds 1-1/2" you must ALWAYS do PWHT.

 

[SnTMan]

This is one of those rare cases where the Code language reads exactly as it means

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[SmallInfo]

Thanks Maslov.
SnTMan, its clear now.