atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Schedule 40 or 80 PVC for underground pulls

Here is a copy/paste of the exact wording of the Code (off Google search of course):

Rigid nonmetallic Schedule 40 PVC conduit is suitable for underground use by direct burial or encasement in concrete. Unless marked “Underground Use Only” or equivalent wording, Schedule 40 conduit is also suitable for above ground use indoors or outdoors exposed to sunlight and weather where not subject to physical damage.

Schedule 80 conduit has a reduced cross-sectional area available for wiring space and is suitable for use wherever Schedule 40 conduit may be used. The marking “Schedule 80” identifies the conduit as suitable for use where exposed to physical damage and for installations on poles to comply with Section 352.10(F) and 352.12

Note the KEY words that dictate the use of 40 or 80 is "subject to physical damage"....