The reference (dated 2010) from Jennifer125 mentions "BS 4232", but this standard was withdrwawn in 1990 and replaced by BS 7079-A1 in 1989 and subsequently by BS ISO 8501-x in 1995.
It does not speak of "degrees", but of qualities, equivalent to grades:
Title Specification for surface finish of blast-cleaned steel for painting
Abstract First, second and third qualities of surface finish (cleanliness and roughness). Diagrammatic indications of second and third qualities.
:
Withdrawn Date 30 November 1990
http://shop.bsigroup.com/en/ProductDetail/?pid=0000000000100...
BS EN ISO 8503-1:1995, BS 7079-C1:1989
Preparation of steel substrates before application of paints and related products. Surface roughness characteristics of blast-cleaned steel substrates.
:
Descriptors Steels, Surface properties, Surfaces, Painting, Surface treatment, Cleaning, Blast-cleaning, Abrasive processes, Mechanical cleaning, Roughness (surface), Surface-roughness measurement, Grades (quality), Calibration, Dimensional tolerances, Comparators, Linear measuring instruments, Test equipment, Profile measurement
http://shop.bsigroup.com/en/ProductDetail/?pid=0000000000002...
The translation workplace 
peer agreement (net): +1
