5
Clearance above grade, veranda,
porch, deck, or balcony
A=
6 inches (15 cm.) for appliances
£
10,000 Btuh (3 kW), 9 inches (23
cm)
for appliances
>
10,000 Btuh (3 kW)
and
£
50,000 Btuh (15 kW), 12
inches (30 cm) for appliances
>
50,000 Btuh (15 kW)
6 inches (15 cm.) for appliances
£
10,000 Btuh (3 kW), 12 inches
(30 cm) for appliances
>
10,000 Btuh
(3 kW) and
£
100,000 Btuh (30 kW),
36 inches (91 cm) for appliances
>
100,000 Btuh (30 kW)
Clearance to nonmechanical air
supply inlet to building or the
combustion air inlet to any other
appliance
J=
Canadian Installations
Clearance to window or door that
may be opened
B=
3 feet (91 cm) above if within 10 feet
(3 m) horizontally
6 feet (1.83 m)
Clearance to a mechanical air
supply inlet
K=
6 inches (15 cm) for appliances
£
10,000 Btuh (3 kW), 12 inches (30
cm) for appliances
>
10,000 Btuh
(30 kW), 36 inches (91 cm) for
appliances
>
100,000 Btuh (30 kW)
6 inches (15 cm), for appliances
£
10,000 Btuh (3 kW), 9 inches (23
cm) for appliances
>
10,000 Btuh (3
kW) and
£
50,000 Btuh (15 kW), 12
inches (30 cm) for appliances
>
50,000 Btuh (15 kW)
Clearance to permanently closed
window
C=
*
7 feet (2.13 m)†
Clearance above paved sidewalk
or paved driveway located on
public property
L=
*
*
V
ertical clearance to ventilated sof
fit
located above the terminal within a
horizontal distance of 2 feet (61 cm)
from the center line of the terminal
D=
*
*
*
12 inches (30 cm) ‡
1
2
†
‡
M=
Clearance to unventilated sof
fit
E=
*
*
Clearance to outside corner
F=
*
*
Clearance to inside corner
G=
*
*
T
o each side of the center line
extended above meter/regulator
assembly
H=
3 feet (91 cm) within a height 15
feet (4.5 m) above the
meter/regulator assembly
*
*
Clearance to service regulator vent
outlet
I=
3 feet (91 cm)
*
US Installations
In accordance with the current CSA
B149.1, National Gas and Propane Installation Code
In accordance with the current
ANSI Z223.1/NFP
A
54, National Fuel Gas Code
A
vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family
dwellings and serves both dwellings.
Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor
.
*
For clearances not specified in
ANSI Z223.1/NFP
A
54 or CSA
B149.1:
“Clearance in accordance with local installation codes and the requirements of the gas
supplier
.”
Canadian Installations
US Installations
12 inches (30 cm)
12 inches (30 cm)
1
2
1
2
V
ent
T
erminal Clearances
E
A
A
H
H
I
K
J
X
X
C
F
INSIDE
CORNER DET
AIL
FIXED
CLOSED
FIXED
CLOSED
OPERABLE
OPERABLE
VENT TERMINAL
X
AIR SUPPL
Y
INLET
AREA
WHERE TERMINAL
IS NOT PERMITED
Clearance under veranda, porch,
deck, or balcony
