Design Factor of Finger Type Slug Catcher

I am working on Design of a finger type slug catcher that is used for crude oil-sour gas separation in Musandam,Oman

We are using ASME B31.8-2010 Code for the design of finger type slug catcher

The Design factor depends on location classes specified in article 804.2 ASME B31.8

How to specify of 1mile (1.6-km) Section around slug catcher since it is about 80m in length?

Would I use para.840.2.1d to specify 1mile (1.6-km) Section for slug catcher since it's length is shorter than 1.6km in length?

Thank you for your help