Optima Installation and Operation Manual
32
7.4.2 Table of Clearance Reduction Percentages
Type of shield
Clearances may be
reduced by these
percentages
Sides
and rear %
Top %
(ceiling)
Sheet metal, a minimum of 24
gauge (0.61 mm) in thickness ,
spaced out at least 25 mm (1 in)*
by non-combustible spacers
67
50
Ceramic tiles, or equivalent non-
combustible material, on non-
combustible board spaced out at
least 25 mm (1 in)* by non-
combustible spacers
50
33
Ceramic tiles, or equivalent non-
combustible material, on non-
combustible
board,
with
a
minimum of 24 gauge (0.61 mm)
sheet metal backing spaced out at
least 25 mm (1 in)* by non-
combustible spacers
67
50
Brick, spaced out at least 25 mm
(1 in)* by non-combustible spacers
50
N/A
Brick, with a minimum of 24 gauge
(0.61 mm) sheet metal backing,
spaced out at least 25 mm (1 in)*
by non-combustible spacers
67
N/A
* In Canada this space can be 21 mm (7/8 in)
