Permanently energized circuits
(a) Those parts of the electrical installation including the leads which shall remain energized
when the battery master switch is open, shall be suitable for use in hazardous areas. Such
equipment shall meet the general requirements of IEC 60079, parts 0 and 143 and the
additional requirements applicable from IEC 60079, parts 1, 2, 5, 6, 7, 11, 15 or 18;
(b) For the application of IEC 60079 part 143, the following classification shall be used:
Permanently energized electrical equipment including the leads which is not subject to
188.8.131.52 and 184.108.40.206 shall meet the requirements for Zone 1 for electrical equipment in general
or meet the requirements for Zone 2 for electrical equipment situated in the driver's cab. The
requirements for explosion group IIC, temperature class T6 shall be met.
However, for permanently energized electrical equipment installed in an environment where
the temperature caused by non-electrical equipment situated in that environment exceeds
the T6 temperature limit, the temperature classification of the permanently energized
electrical equipment shall be at least that of the T4 temperature class.
(c) The supply leads for permanently energised equipment shall either comply with the
provisions of IEC 60079, part 7 ("Increased safety") and be protected by a fuse or automatic
circuit breaker placed as close to the source of power as practicable or, in the case of
"intrinsically safe equipment", they shall be protected by a safety barrier placed as close to
the source of power as practicable.
Bypass connections to the battery master switch for electrical equipment which must remain energized
when the battery master switch is open shall be protected against overheating by suitable means, such
as a fuse, a circuit breaker or a safety barrier (current limiter).
3 The requirements of IEC 60079 part 14 do not take precedence over the requirement of this Part.
Motor vehicles and trailers intended for use as transport units for dangerous goods shall fulfil all
relevant technical requirements of ECE Regulation No.134, as amended, in accordance with the dates
of application specified therein.
EX/II, EX/III, FL and AT vehicles shall fulfil the requirements of ECE Regulation No.134, Annex 5.
Prevention of fire risks
The following technical provisions shall apply in accordance with the table of 9.2.1.
Fuel tanks and cylinders
The fuel tanks and cylinders supplying the engine of the vehicle shall meet the following
(a) In the event of any leakage under normal conditions of carriage, the liquid fuel or the liquid
phase of a gaseous fuel shall drain to the ground and not come into contact with the load or
hot parts of the vehicle;
(b) Fuel tanks for liquid fuels shall meet the requirements of ECE Regulation No. 345; fuel tanks
containing petrol shall be equipped with an effective flame trap at the filler opening or with a
closure enabling the opening to be kept hermetically sealed. Fuel tanks and cylinders for LNG
and for CNG respectively shall meet the relevant requirements of ECE Regulation No. 1106.
Fuel tanks for LPG shall meet the relevant requirements of ECE Regulation No. 677.
(c) The discharge opening(s) of pressure relief devices and/or pressure relief valves of fuel tanks
containing gaseous fuels shall be directed away from air intakes, fuel tanks, the load or hot
parts of the vehicle and shall not impinge on enclosed areas, other vehicles, exterior-mounted
systems with air intake (i.e. air-conditioning systems), engine intakes, or engine exhaust. Pipes
of the fuel system shall not be fixed on the shell containing the load.
4 ECE Regulation No. 13 (Uniform provisions concerning the approval of vehicles of categories M, N and O
with regard to braking).
5 ECE Regulation No. 34 (Uniform provisions concerning the approval of vehicles with regard to the prevention
of fire risks)
6 ECE Regulation No. 110 (Uniform provisions concerning the approval of:
I. Specific components of motor vehicles using compressed natural gas (CNG) and/or liquefied natural
gas (LNG) in their propulsion systems;
II. Vehicles with regard to the installation of specific components of an approved type for the use of
compressed natural gas (CNG) and/or liquefied natural gas (LNG) in their propulsion system).
7 ECE Regulation No. 67 (Uniform provisions concerning the approval of:
I. Approval of specific equipment of vehicles of category M and N using liquefied petroleum gases in
their propulsion system
II. Approval of vehicles of category M and N fitted with specific equipment for the use of liquefied
petroleum gases in their propulsion system with regard to the installation of such equipment)
The engine propelling the vehicle shall be so equipped and situated to avoid any danger to the load
through heating or ignition. The use of CNG or LNG as fuel shall be permitted only if the specific
components for CNG and LNG are approved according to ECE Regulation No. 1106 and meet the
provisions of 9.2.2. The installation on the vehicle shall meet the technical requirements of 9.2.2 and
ECE Regulation No. 1106. The use of LPG as fuel shall be permitted only if the specific components
for LPG are approved according to ECE Regulation No. 677 and meet the provisions of 9.2.2. The
installation on the vehicle shall meet the technical requirements of 9.2.2 and ECE Regulation No. 677.
In the case of EX/II and EX/III vehicles the engine shall be of compression-ignition construction
using only liquid fuels with a flashpoint above 55 °C. Gases shall not be used.
The exhaust system (including the exhaust pipes) shall be so directed or protected to avoid any danger
to the load through heating or ignition. Parts of the exhaust system situated directly below the fuel
tank (diesel) shall have a clearance of at least 100 mm or be protected by a thermal shield.
Vehicle endurance braking
Vehicles equipped with endurance braking systems emitting high temperatures placed behind the rear
wall of the driver's cab shall be equipped with a thermal shield securely fixed and located between this
system and the tank or load so as to avoid any heating, even local, of the tank wall or the load.
In addition, the thermal shield shall protect the braking system against any outflow or leakage, even
accidental, of the load. For instance, a protection including a twinshell
shield shall be considered