A. In addition to
the definitions in
R13-13-101, in this
Article, unless otherwise specified:
"AGA" means the American Gas Association.
"ANSI" means the American National Standards
Institute.
"Angle of departure" means the area above an imaginary line
that extends from the bottom outside edge of the rear bumper on a vehicle to
the point at which a tire on the vehicle's rear drive axle touches the
ground.
"Appurtenance" means an item connected to an opening of a
natural-gas pressure vessel to make the natural-gas pressure vessel gas-tight.
This includes pressure relief devices, shutoff, backflow, excess-flow, and
internal valves, liquid-level and pressure gauges, and plugs.
"Approved" means acceptable to the Department.
"ASE" means National Institute of Automotive Service
Excellence.
"Bracket" means rubber-lined, hoop and cradle mounting
hardware supplied or approved by a pressure-vessel manufacturer to hold a
natural-gas pressure vessel in a rack.
"CNG" means compressed natural gas, a combustible mixture of
hydro-carbon gases and vapors, principally methane, that is reduced in volume
by pressure for use as a vehicular fuel.
"Fuel-distribution assembly" means a device that regulates
the flow of fuel from a natural-gas pressure vessel to a vehicle engine.
"Fuel line" means a pipe, tubing, or hose, and all related
fittings through which natural gas passes on a vehicle.
"Installer" means a person who converts a school bus from the
use of gasoline to the use of CNG by attaching a natural-gas fuel system to the
school bus after the school bus is manufactured.
"Listed" means included in a publication of an approved
organization that is concerned with product evaluation, conducts periodic
inspection of equipment or material, and includes equipment or material in the
approved organization's publication only if the equipment or material complies
with appropriate standards or performs in a specified manner.
"NFPA" means the National Fire Protection Association, which
is located at 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101, and
which is accessible at (617) 770-3000 and www.nfpa.org.
"NGV-1" means specific standards set by the American National
Standards Institute and American Gas Association for the refueling connection
device of a natural-gas vehicle.
"NGV-2" means specific standards set by the American National
Standards Institute and American Gas Association for a vehicle-on-board
natural-gas pressure vessel.
"Natural gas" means a combustible mixture of hydrocarbon
gases and vapors, principally methane.
"Natural-gas fuel system" means a group of items including a
pressure vessel and all attached valves, piping, and appurtenances that form a
network for distributing natural gas to a vehicle engine.
"Operating pressure" means the internal force that a
manufacturer intends for a natural-gas pressure vessel to achieve during normal
operation of the vehicle to which the natural-gas pressure vessel is
attached.
"Out-of-service" means not compliant with these rules, NFPA
52, or manufacturer's instructions for installation, maintenance, or
repair.
"Owner" means a private business, school, or school district
that owns a school bus.
"PSI" means pound per square inch.
"Pressure-relief device" means a mechanism that is installed
in a natural-gas pressure vessel or integrated with a valve, that is operated
by temperature, pressure, or both, and that releases the CNG in the natural-gas
pressure vessel in specific emergency conditions. A pressure-relief device for
a U.S. Department of Transportation or Canada Transport natural-gas pressure
vessel also includes a mechanism capable of protecting a partially charged
natural-gas pressure vessel.
"Pressure vessel" means a cylinder that is part of a
natural-gas fuel system and that is constructed, inspected, and maintained in
accordance with U.S. Department of Transportation or Canada Transport
regulations or ANSI/AGA NGV2, Basic Requirements for Compressed Natural Gas
Vehicle (CNGV) Fuel Containers, or CSA B51, Boiler, Pressure Vessel and
Pressure Piping Code.
"Pressure-vessel valve" means a mechanical device connected
directly to a natural-gas pressure vessel opening that regulates the flow of
CNG from the natural-gas pressure vessel to the vehicle engine.
"Rack" means a metal structure that surrounds a natural-gas
pressure vessel mounted on a vehicle and is secured to the vehicle frame by a
method capable of withstanding a static up, down, left, right, forward, or
backward force of eight times the weight of the fully pressurized natural-gas
pressure vessel.
"UL" means the Underwriters' Laboratory, Inc.
B. Applicability and enforcement
date of this Section
1. This Section applies
to school buses that are manufactured to use only gasoline or diesel fuel and
are converted to use CNG, in whole or in part.
2. The Department shall enforce this Section
beginning 180 days after it is filed with the Office of the Secretary of State.
After the beginning enforcement date, a school bus that is manufactured to use
only gasoline or diesel fuel and is converted to use CNG, in whole or in part,
shall meet the requirements of this Section when the school bus is introduced
into Arizona or when the school bus is converted to natural-gas power. A school
bus introduced into Arizona and powered in whole or in part by CNG before the
beginning enforcement date of this Section shall meet the requirements of this
Section or those at A.A.C.
R17-4-611 .
3. After the beginning enforcement date of this Section, the Department shall
not approve a school bus manufactured to use only gasoline or diesel fuel and
converted to use CNG, in whole or in part, unless the natural-gas fuel system
meets the requirements of this Section.
C. Insurance
1. An owner shall not contract with an
installer unless the installer has insurance coverage provided by a
comprehensive general liability broad form insurance policy that is approved by
the Department. The insurance policy shall include coverage for liability
resulting from:
a. Completed installation
operations,
b. Harm that arises on
the installer's premises, and
c.
Breach of contract by the installer.
2. In addition to the liability coverage
described in subsection (C)(1), an owner shall ensure that either:
a. The installer has insurance coverage for
liability resulting from harm that arises from subcontracted work performed by
an independent contractor, or
b. An
independent contractor who performs work for the installer under an agreement
has an insurance policy that provides coverage for liability resulting from
harm caused by the independent contractor's work.
3. An owner shall not contract with an
installer unless the installer has an insurance policy that provides at least
$1 million liability coverage per occurrence both for bodily injury and for
property damage.
4. An owner shall
not contract with an installer unless the issuer of the installer's insurance
policies described in subsections (C)(1) through (C)(3) names the Department as
an additional insured on each policy and keeps the Department informed of any
change in the status of each policy.
5. An owner shall obtain the Department's
approval of the installer's insurance policy by submitting proof of the
insurance described in subsections (C)(1) through (C)(3) to the Department
before entering a contractual agreement with the installer for the installation
of a natural-gas fuel system on a school bus.
6. If an owner acts as an installer, the
owner shall maintain the insurance required by this Section.
7. The Department shall approve an
installer's insurance policy, proof of which is submitted by an owner in
accordance with subsection (C)(5), if the policy conforms to the requirements
in subsections (C)(1) through (C)(3). The Department shall send written notice
of its decision to approve or disapprove the installer's insurance policy to
the owner within 15 days from receipt of the proof of insurance.
D. General requirements for
installing a natural-gas fuel system
1.
Converting a school bus to use of CNG, whether in whole or in part, is not an
alteration as defined in
R13-13-101.
2. Unless specifically provided otherwise in
this Section, when installing a natural-gas fuel system, an installer shall use
parts and equipment and perform work in a manner that meets or exceeds the
standards of NFPA 52, Standard for Compressed Natural Gas (CNG) Vehicular Fuel
Systems, 1995 (and no later editions or amendments), Quincy, MA, which is
incorporated by this reference and on file with the Department and the Office
of the Secretary of State.
3. An
installer shall use only UL-listed or AGA-approved carburetor equipment when
installing a natural-gas fuel system on a school bus.
4. An installer shall meet or exceed the
recommended guidelines provided by the manufacturers of all parts of a
natural-gas fuel system when installing the natural-gas fuel system on a school
bus.
5. An installer shall ensure
that installation of a natural-gas fuel system on a school bus is performed by
an individual who has proof of training provided by the manufacturer of the
natural-gas fuel system or ASE alternative fuels certification.
6. If a school bus is converted from the use
of gasoline or diesel fuel to the dedicated use of CNG, the installer shall
remove the gasoline or diesel-fuel tank and accompanying gasoline or
diesel-fuel system parts from the school bus.
E. Natural-gas pressure vessel: An installer
shall use only a natural-gas pressure vessel that is certified by its
manufacturer as meeting or exceeding the NGV2 standards and as being U.S.
Department of Transportation or ANSI listed. An installer shall use the
natural-gas pressure vessel manufacturer's recommended bracket.
F. Installing a natural-gas pressure vessel
1. An installer shall securely attach a rack
to the frame of a school bus in the following manner:
a. By drilling no holes in the school bus
frame that exceed the manufacturer's requirements; and
b. By using no welding on and applying no
heat to the school bus frame.
2. When installing a natural-gas fuel system
on a school bus, an installer shall locate the natural-gas pressure vessel and
its appurtenances on the vehicle frame as follows:
a. Below the driver's or passengers'
compartment;
b. So no part
protrudes:
i. In front of the front
axle,
ii. Beyond the outside face
of the rear bumper, or
iii. Beyond
the sides of the school bus;
c. Inside a rack; and
d. So the minimum clearance between the road
and the lowest part of the natural-gas pressure vessel and its rack on a school
bus loaded to its gross vehicle weight rating, is:
i. No fewer than 7 inches (17.5 mm) for a
school bus with a wheel base fewer than or equal to 127 inches (323 mm);
or
ii. No fewer than 9 inches (22.5
mm) for a school bus with a wheel base greater than 127 inches (323
mm).
3. If
the natural-gas pressure vessel and its appurtenances are located behind the
rear axle of the school bus, in addition to the requirements in subsection
(F)(3), an installer shall locate the natural-gas pressure vessel as follows:
a. Below the floor line, and
b. Above the school bus' angle of
departure.
G.
Protecting a natural-gas pressure vessel. To protect a natural-gas pressure
vessel and its appurtenances from damage, an installer shall:
1. Surround the natural-gas pressure vessel
with a stone guard on all sides that are not protected by the natural barriers
of the vehicle. The stone guard shall not be attached to the natural-gas
pressure vessel. If the stone guard protects a valve, it shall be made of at
least 16-gauge steel. If the stone guard does not protect a valve, it shall be
made of at least 3/16-in. mesh with openings no greater than 1 in.;
2. Place a resilient, non-absorbent gasket
between the natural-gas pressure vessel and its brackets in a manner that
prevents the brackets from directly contacting the natural-gas pressure
vessel;
3. Ensure that the weight
of the natural-gas pressure vessel is not supported, in whole or in part, by an
appurtenance; and
4. Place a shield
between, but not attached to, the natural-gas pressure vessel and the vehicle
exhaust system if the natural-gas pressure vessel or the fuel lines are located
fewer than 8 inches from the exhaust system. The shield shall be constructed of
at least 18-gauge metal.
H. Safety and check valves: An installer
shall equip a natural-gas fuel system with:
1.
Either an automatic fuel supply shut-off valve that is placed between the
pressure vessel fuel-pressure regulator and the fuel distribution assembly and
activated by engine vacuum or oil pressure, or an electronic fuel injector;
and
2. Either a manual or
automatically controlled shut-off valve that enables the natural-gas pressure
vessel to be isolated from the remainder of the natural-gas fuel system. If a
manual shut-off valve is used, it shall:
a.
Have no more than 90° rotation from the opened to the closed
position;
b. Have a red valve
handle;
c. Be placed in an
accessible location; and
d. Have
"ESV" printed on the school bus at the access location to the manual shut-off
valve, in 2-in. to 4-in., unshaded, red letters.
I. Installation of fuel lines. An
installer shall:
1. Use fuel lines constructed
of seamless stainless steel that has been tested and certified by the
manufacturer to an operating pressure of 3600 PSI with a 4:1 safety
factor;
2. Mount and brace fuel
lines to the vehicle frame in a manner that minimizes vibration;
3. Secure fuel lines to the vehicle frame at
least every 24 inches with rubber-lined fasteners;
4. Protect fuel lines that pass through any
structural member with rubber grommets, bulkhead fittings, or both;
5. Cause fuel lines that run to the engine to
follow the main frame channel; and
6. Install an access door that is at least 70
square inches if access to the fill receptacle and fuel pressure gauge is
through the school bus body. The words "CNG Fill" shall be printed on the
school bus body, immediately above the access door, in 2-in. to 4-in., unshaded
letters.
J. Installation
of Venting System. An installer shall ensure that in addition to meeting the
requirements in NFPA 52, all vent exits are aimed toward the ground.
