Standards and Recommendations - Road Lighting: Fundamentals, Technology and Application - page 251

Table 17.5 Limiting
requirements for the uplight
from ornamental street lights
according to lighting zone.
(IDA-IES 2011 )

Lighting zone U rating

LZ0 U0

LZ1 U1

LZ2 U2

LZ3 U3

LZ4 U4

lighting of monuments, buildings and structures, the same ordinance gives more
comprehensive regulations. The regulations of the ordinance are given for different
lighting zones LZ0 - LZ4, which are very similar to the CIE environmental zones
E0 - E4. The lighting parameters that the ordinance uses have already been described
in Sect 16.2.2 and were summarised in Table 16.2.

17.4.1 IDA-IESNA Ordinance for Road Lighting

Since the MLO ordinance is a free publication without copyright, the full Table
values are reproduced in this topic where relevant. The ordinance states that all street
lighting, with the exception of ornamental street lighting, shall have no light emitted
above 90 ⓦ (the horizontal). Ornamental street lights must meet the U-rating of the
BUG luminaire classification system as specified in Table 17.5 . Table 17.6 gives an
indication of what these U ratings mean in terms of luminous flux radiated above the
horizontal.

17.4.2 IDA-IESNA Ordinance for Sports, Area and Architectural

Lighting

The ordinance requires a curfew time to be set for these types of lighting installations,
after which the lighting has to comply with a maximum luminous flux limit and either
a limit of the BUG rating or a limit of the lighting on the surfaces of a virtual enclosure
around the area to be lighted.

Table 17.6 Maximum luminaire lumens for the different U-ratings of the BUG system (Here only
the maximum-permitted lumen above the horizontal are shown. For the U ratings, the BUG rating
system also specifies the maximum lumens for the area just below the horizontal). (IDA-IES 2011 )
lum
(lumen)

Solid angle U0 U1 U2 U3 U4 U5

UH (above 100 ⓦ ) 0 10 100 500 1000 > 1000

UL (90 - 100 ⓦ )

0 10 100 500 1000 > 1000