EN 40 Part 2 sets out the definitions appropriate to lighting columns and the most essential are given below for convenience together with some additional information based on experience in the UK.
a) Nominal Height
This is the height of the column and bracket combination from ground level to the axis at the point of entry into the luminaire at the luminaire fixing.
b) Bracket Projection
This is the horizontal distance from the vertical axis of the column to the point of entry into the luminaire at the luminaire fixing, frequently incorrectly called "outreach" which is the horizontal distance from the vertical column axis to the centre of the light source (used for lighting design). It is important to state if single arm, double arm or multiple arm brackets are required.
c) Flange Plates
The structural plate at right angles to the column axis at, or near, ground level to secure the column to a foundation or structure by means of foundation bolts, frequently incorrectly called "base plate" (see below).
d) Planting Depth
The length of column shaft below the intended ground level, known as the root, for embedment in the backfilled soil to provide stability to the column shaft.
e) Base Plates
An anti-sink plate at the bottom of the root of a column which may either be fixed to the column or supplied separately.
f) Base Compartment(s)
The area at the base of a column shaft to house electrical equipment. While a single compartment is usually required, double door columns are also available for double arm brackets or to house additional equipment. It should be noted that the sizes of the door openings have been standardised in the UK to 600mm by 115mm or 500mm by 100 mm.
g) Luminaire Weight & Windage
The effective weight and projected area of the luminaire in the vertical plane, used for column design or selection for appropriate wind resistance.
h) Luminaire Fixing
The extension of the bracket or column shaft onto which the luminaire is fixed, usually known as the "spigot" although this term is not used by EN 40.
i) Post Top Columns
Where there is no projecting bracket, although a vertical extension may be used, and the luminaire is fixed on its axis directly above the column shaft.
j) Post Top Mount Columns
Where the spigot is similar to that for post top columns, with or without an extension, and the luminaire is fixed onto this spigot but projects sideways.