Torque for Threaded PVC Pipe Joints

[FLisa]

I have been looking for a source of proper torque for pipe threads on PVC Schedule 80 pipe. Most sources list a number of turns method (2 turns past finger tight, 1/2 turn past hand tight, etc.) This seems very open to me. Whose fingers and whose hands?

 

[TWong]

The Machinery's Handbook provideds a length in inches for 'handtight engagement'. (pg 1613, 23rd edition) Tommy