Land Transport Rule

Seats and Seat Anchorages 2002

Rule 32004

Contents

Objective of the rule

Extent of consultation

Part 1     Rule requirements

Section 1     Application

Section 2     Vehicle standards and other safety requirements

Section 3     Modification and repair

Section 4 Responsibilities

Part 2     Definitions

 

Objective of the rule

Land Transport Rule: Seats and Seat Anchorages 2002 is one of a series of rules that sets safety requirements and standards for systems and components in vehicles operating in New Zealand. This rule covers the design, construction and maintenance of seats and seat anchorages. The aim of the rule is to ensure that seats meet at least the minimum strength standards and are securely anchored to the structure of the vehicle.

The rule specifies requirements with which a vehicle must comply for certification purposes and that apply throughout the vehicle’s on-road life.

Approved vehicle standards are ‘incorporated by reference’ in the rule in accordance with section 165 of the Land Transport Act 1998, so that they are, effectively, part of the rule. A choice of overseas standards provides flexibility within agreed safety parameters, and enables New Zealand to align with world best practice. The approved vehicle standards apply only to specified vehicles, and only to those vehicles manufactured from the dates set out in the rule.

This rule applies throughout the on-road life of a vehicle by specifying requirements for seats and their anchorages at: first registration in New Zealand; repair; modification; in-service inspection and other aspects of continuing compliance. The rule is an essential element of the safety framework governing vehicles in New Zealand. It links with, and provides a means of assessment for, Land Transport Rule: Vehicle Standards Compliance 2002, which sets procedures for vehicle inspection and certification.

The rule states who is responsible for ensuring compliance with its requirements: operators, repairers, modifiers, vehicle inspectors and inspecting organisations, manufacturers and retailers. This links the rule to provisions of the Land Transport (Offences and Penalties) Regulations 1999.

 

Extent of consultation

The consultation process for this rule began formally in March 1994, with the release of the red (registered interest groups) draft of the rule together with the red draft of the Seatbelt Anchorages Rule and other draft rules relating to vehicle standards. The red drafts were sent to 240 organisations and individuals who had either registered an interest in the rules or who were considered likely to be interested in the rules. Twenty-seven written submissions were received.

The ensuing yellow drafts of these rules were released for public consultation in August 1994. The LTSA received 61 written submissions on the yellow drafts. All submissions were analysed and taken into account in redrafting the rules. Twenty-seven people attended a public forum with LTSA representatives to discuss key issues. There was also subsequent formal and informal discussion with interested groups and individuals.

The red draft of a proposed Seatbelts Rule was released in May 1995. That rule set out requirements for seatbelts and their location in motor vehicles, but did not include their anchorage requirements. Forty-five submissions were received and analysed.

As a result of consultation, it was decided that all the seat-related rules would be produced together. The yellow drafts of the Seats and Seat Anchorages Rule and the Seatbelts and Seatbelt Anchorages Rule were released for public consultation in January 1997. Notice of intention to make the rules and of the availability of the draft rules for comment was published in the five metropolitan daily newspapers and in the New Zealand Gazette. The draft rules were also publicised in a national Maori newspaper and were sent to national libraries and transport organisations overseas. Copies were also sent to those who had registered an interest in the rules and to those who had commented on the earlier drafts.

The LTSA received 58 submissions and took into account the comments in redrafting the rules. The redrafted rules were released in June 1998 as green drafts for comment by key interest groups. Fourteen submissions were received and these were taken into account in redrafting the rules.

The LTSA was involved in on-going consultation and discussion with industry groups on issues of concern in the two rules. Most of the major industry groups consulted are represented on the Vehicle Standards Advisory Committee.

A final round of consultation on this rule was undertaken during July and August 2001 by way of the Vehicle Safety Proposals Consultation Paper, which was released on 28 June 2001 for public comment. Although the consultation paper did not include any proposals relating to seats and seat anchorages, both this rule and the Seatbelts and Seatbelt Anchorages Rule were released concurrently with the consultation paper for final consultation. Six submissions were received on this rule.

Issues identified in submissions were taken into account in redrafting this rule before it was submitted to Cabinet, and to the Minister of Transport for signature.

 

Part 1     Rule requirements

Section 1     Application

1.1     Title

This rule is Land Transport Rule: Seats and Seat Anchorages 2002.

 

1.2     Scope of the rule

1.2(1)     This rule applies to seats and seat anchorages in all motor vehicles, except vehicles of Classes TA, TB, TC and TD in Table A in Part 2.

1.2(2)     This rule specifies requirements:

1.2(3)     In this rule, every reference to a vehicle inspector or inspecting organisation is a reference to a certifier for the purposes of the Land Transport (Offences and Penalties) Regulations 1999 and the Land Transport (Certification and Other Fees) Regulations 1999.

 

1.3     Date when rule comes into force

This rule comes into force on 1 April 2002.

 

1.4     Application of rule provision

1.4(1)     If there is a conflict between a provision of this rule and the corresponding provision of a document incorporated by reference in the rule, the provision of the rule applies.

1.4(2)     If there is a conflict between a provision of this rule and a provision of Land Transport Rule: Vehicle Standards Compliance 2002, the provision of Land Transport Rule: Vehicle Standards Compliance 2002 applies.

1.4(3)     A seat or seat anchorage does not have to comply with an approved vehicle standard in this rule if:

 

Section 2     Vehicle standards and other safety requirements

2.1     Requirements for motor vehicles

2.1(1)     Seats and seat anchorages in a motor vehicle must comply, as specified in Table 2.1:

2.1(2)     Seats and seat anchorages in a low volume vehicle must comply, as specified in Table 2.2, with the requirements of the Low Volume Vehicle Code that are applicable at the date of certification or recertification of the vehicle as a low volume vehicle.

2.1(3)     Retrofitting of a seat anchorage in a motor vehicle is a modification that must comply with the relevant requirements in section 3.

 

2.2     General safety requirements

2.2(1)     Seats and seat anchorages in a motor vehicle must be safe, strong, in sound condition, in good working order and compatible in strength with each other and with the vehicle’s structure.

2.2(2)     The driver’s seat and its anchorages must be designed, constructed and maintained to enable the driver to have proper control of the motor vehicle.

2.2(3)     Seats and seat anchorages must be securely attached to the motor vehicle’s structure.

2.2(4)     When a seatbelt or any part of a seatbelt is integral to a seat, the seat and the seat anchorages must be compatible in strength with the seatbelt or with that part of the seatbelt attached to the seat, as appropriate.

2.2(5)     In assessing whether 2.2(1) to 2.2(3) are complied with, a person in section 4 may take into account evidence that a seat or seat anchorage is within the motor vehicle manufacturer’s operating limits.

2.2(6)     In assessing whether 2.2(4) is complied with, a person in section 4 may take into account evidence that a seat or seat anchorage is within the motor vehicle manufacturer’s or component manufacturer’s operating limits, including the type of seatbelt for which it was originally designed.

 

Table 2.1     Requirements for seats and seat anchorages in a motor vehicle that is not a low volume vehicle

Class Motor vehicle
manufactured before
1 October 2002

Motor vehicle
manufactured on or
after 1 October 2002
MA, MB, MC, NA General safety
requirements
General safety
requirements and
approved vehicle
standard
AB, LA, LB, LC, LD,
LE1, LE2, MD1, MD2,
MD3, MD4, ME, NB, NC
General safety requirements
Motor vehicles not in
Table A

 

Table 2.2     Requirements for seats and seat anchorages in a low volume vehicle1

Class Light motor vehicle last modified on or after
1 January 1992 and certified as a low volume
vehicle
Low volume vehicle General safety requirements and Low Volume
Vehicle Code

Note:
1 The concept of low volume vehicles and, hence, certification for such vehicles was not initiated until after 1991. A motor vehicle last modified before 1 January 1992 does not have to comply with the Low Volume Vehicle Code, provided the vehicle has been continuously registered in New Zealand. It must, however, comply with the general safety requirements in 2.2.

 

2.3     Approved vehicle standards

2.3(1)     If fitted as original equipment and specified in Table 2.1:

2.3(2)     The approved vehicle standards for seats and seat anchorages are:

 

    Version of vehicle standards

2.3(3)     A seat that is fitted as original equipment must comply with the version of an approved vehicle standard that:

2.3(4)     A seat anchorage that is fitted as original equipment must comply with the version of an approved vehicle standard that is applicable in the relevant standard-setting jurisdiction to the date of manufacture of the motor vehicle or as specified in the standard.

2.3(5)     A replacement or retrofitted seat or seat anchorage may comply with a more recent version of an approved vehicle standard than that in 2.3(3) or 2.3(4) only if the safety performance of the motor vehicle is not adversely affected.

 

    Approved vehicle standards include amendments to standards

2.3(6)     An approved vehicle standard in 2.3(2) includes all amendments to that standard, some of which may apply to classes of motor vehicle additional to those covered by the original standard.

 

    Compliance with vehicle standards

2.3(7)     A seat or seat anchorage complies with an approved vehicle standard if:

2.3(8)     A seat or seat anchorage, or any of its components, that is manufactured, stocked or offered for sale in New Zealand and that is intended for fitting in a motor vehicle to be operated on a New Zealand road, must not prevent the vehicle from complying with one or more of the approved vehicle standards in 2.3(2), unless specifically designed for a vehicle:

2.3(9)     A motor vehicle must comply with an approved vehicle standard in this rule, unless:

 

Section 3     Modification and repair

3.1     Modification

3.1(1)     A modification to a motor vehicle that affects the performance of a seat or seat anchorage:

 

    Light motor vehicles

3.1(2)     A modification, on or after 1 January 1992, to a seat or seat anchorage in a light motor vehicle, or a modification to a light motor vehicle that affects the performance of a seat or seat anchorage, must comply with 2.2 and with:

 

    Heavy motor vehicles

3.1(3)     A modification to a seat or seat anchorage in a heavy motor vehicle, or a modification to a heavy motor vehicle that affects the performance of a seat or seat anchorage, must comply with 2.2.

3.1(4)     In assessing whether 2.2 has been complied with for the purposes of 3.1(3), a vehicle inspector or inspecting organisation may take into account the technical requirements relating to geometry and load-carrying capacity in any of the approved vehicle standards in 2.3(2) or the Low Volume Vehicle Code.

 

    Motor vehicles modified for a specific purpose

3.1(5)     The requirements of this rule relating to seats and seat anchorages do not apply to a light motor vehicle that has been modified for a specific purpose, provided that a valid low volume vehicle authority card has been issued for the vehicle and its operator in accordance with the Low Volume Vehicle Code.

3.1(6)     A low volume vehicle authority card issued under 3.1(5) must be provided:

 

3.2     Repair

3.2(1)     A repair to a motor vehicle that affects a seat or seat anchorage must restore the damaged or worn seat, seat anchorage or vehicle so that it is within safe tolerance of:

3.2(2)     A repair to a motor vehicle that affects a seat or seat anchorage:

 

Section 4     Responsibilities

4.1 Responsibilities of operators

A person who operates a motor vehicle must ensure that the vehicle complies with this rule.

 

4.2 Responsibilities of repairers

A person who repairs a seat or seat anchorage must ensure that the repair:

 

4.3     Responsibilities of modifiers

A person who modifies a seat or seat anchorage, or a motor vehicle so as to affect the performance of a seat or seat anchorage, must:

 

4.4     Responsibilities of vehicle inspectors and inspecting organisations

A vehicle inspector or inspecting organisation must not certify a motor vehicle under Land Transport Rule: Vehicle Standards Compliance 2002 if they have reason to believe that the vehicle does not comply with this rule.

 

4.5     Responsibilities of manufacturers and retailers

A person may manufacture, stock, or offer for sale a seat, seat anchorage or a component of a seat or seat anchorage, intended for fitting to a motor vehicle to be operated on a New Zealand road, only if the seat, seat anchorage, or component:

 

Part 2     Definitions

Approved vehicle standard
means a vehicle standard in 2.3(2).
Certify
has the same meaning as in Land Transport Rule: Vehicle Standards Compliance 2002.
Class
in relation to vehicles, means a category of vehicle of one of the Groups A, L, M, N and T, as specified in Table A: Vehicle classes.
Director
means the Director of Land Transport Safety appointed under section 186 of the Land Transport Act 1998.
EEC, EC
are abbreviations for directives of the European Economic Community and, later, the European Communities.
Federal Motor Vehicle Safety Standard
is a vehicle standard of the United States of America.
Gross vehicle mass
means either:
  • (a) the maximum permitted mass of a vehicle, which includes the mass of the accessories, the crew, the passengers and load, and is, unless (b) applies, the gross vehicle mass specified (subsequent to the latest modification, if any) by the manufacturer of the vehicle; or
  • (b) if a person approved for the purpose by the Director determines that the gross vehicle mass should differ from that specified by the manufacturer, taking into account evidence on the capability of the systems and components of the vehicle, or the effects of any modification, that mass determined by that person.
Heavy motor vehicle
means a motor vehicle that is either:
  • (a) of Class MD3, MD4, ME, NB, NC, TC or TD; or
  • (b) a vehicle (not of a class specified in Table A: Vehicle classes) with a gross vehicle mass that exceeds 3500 kg.
Light motor vehicle
means a motor vehicle except one defined as a ‘heavy motor vehicle’.
Low volume vehicle
means a motor vehicle of a class in Table A: Vehicle classes, other than Class MD3, MD4, ME, NB, NC, TC or TD, that is:
  • (a) manufactured, assembled or scratch-built in quantities of 200 or less at any one location in any one year, by a manufacturer whose total production of motor vehicles does not exceed 200 units over the same period, and where the construction of the vehicle directly or indirectly affects compliance of the vehicle with any of the vehicle standards prescribed by New Zealand law; or
  • (b) modified uniquely, or in quantities of 200 or less at any one location in any one year, in such a way as to affect the compliance of the vehicle, its structure, systems, components or equipment, with a legal requirement relating to safety performance applicable at the time of the modification.
Low volume vehicle authority card
means a certification document issued by the Low Volume Vehicle Technical Association Incorporated, in accordance with the Low Volume Vehicle Code, that applies to a light motor vehicle modified for a specific purpose including for motor sport activities or for a person with a disability.
Low Volume Vehicle Code
means the code of the Low Volume Vehicle Technical Association Incorporated.
Manufacturer’s operating limits
means:
  • (a) in relation to a motor vehicle, the allowance provided by the vehicle manufacturer in terms of performance capability and dimensions, relative to deterioration, malfunction or damage beyond which the safe performance of the vehicle, as defined by the vehicle manufacturer, is compromised; and
  • (b) in relation to a system, component or item of equipment, incorporated in or attached to a vehicle, the allowance provided by the system, component or equipment manufacturer in terms of performance capability and dimensions, relative to the deterioration, malfunction or damage, beyond which the safe performance of the system, component or item of equipment (and consequently the vehicle) is compromised.
Modify
in relation to a motor vehicle, means to change the vehicle from its original state by altering, substituting, adding or removing any structure, system, component or equipment; but does not include repair.
Motor vehicle
means a vehicle drawn or propelled by mechanical power; and includes a trailer; but does not include:
  • (a) a vehicle running on rails;
  • (b) an invalid carriage;
  • (c) a trailer (other than a trailer designed solely for the carriage of goods) that is designed and used exclusively as part of the armament of the New Zealand Defence Force;
  • (d) a trailer running on one wheel and designed exclusively as a speed measuring device or for testing the wear of vehicle tyres;
  • (e) a vehicle designed for amusement purposes and used exclusively within a place of recreation, amusement, or entertainment to which the public does not have access with motor vehicles;
  • (f) a pedestrian-controlled machine.
Operate
in relation to a vehicle, means to drive or use the vehicle on a road, or to cause or permit the vehicle to be on a road, or to be driven on a road, whether or not the person is present with the vehicle.
Original equipment
means equipment that is fitted by the motor vehicle manufacturer when the vehicle is manufactured.
Phase-in date
means the date specified in an approved vehicle standard from which a model, or model variant, of a vehicle must comply with that standard or part of that standard.
Repair
means to restore a damaged or worn motor vehicle, its structure, systems, components or equipment; and includes the replacement of damaged or worn structures, systems, components or equipment with equivalent undamaged or new structures, systems, components or equipment.
Retrofit
in relation to a seat or seat anchorage in a motor vehicle, means to fit a seat or seat anchorage in a location where a seat or seat anchorage has not been fitted before.
Safe tolerance
means the tolerance within which the safe performance of the vehicle, its structure, systems, components or equipment is not compromised, having regard to any manufacturer’s operating limits.
Scratch-built vehicle
means a motor vehicle that is either:
  • (a) assembled from previously unrelated components and construction materials that have not been predominantly sourced from donors of a single make or model and that, in its completed form, never previously existed as a mass-produced vehicle, although the external appearance may resemble or replicate an existing vehicle; or
  • (b) a modified production vehicle that contains less than the following components from a mass-produced vehicle of a single make and model:
    • (i) 40% of the chassis rails and 50% of the crossmembers, or alternatively 40% of a spaceframe, or 40% of the floorpan of a unitary constructed body, whichever is appropriate; or
    • (ii) for light vehicles, 40% of the bodywork (based on surface area of body panels but not including the floorpan, internal bracing, subpanels, bulkheads or firewall).
Seat
means an assembly, or part of an assembly, intended to seat at least one person, that may or may not be integral to the vehicle structure.
Seatbelt
means an assembly of straps made of webbing or metal with a securing buckle, adjusting devices and attachments, including any device for absorbing energy or for retracting the webbing, that:
  • (a) is able to be anchored to the interior of a vehicle; and
  • (b) is designed to diminish the risk of injury to its wearer in the event of a collision or abrupt deceleration of the vehicle by limiting the mobility of the wearer’s body.
Seat anchorage
means the parts of the vehicle structure to which a seat is attached.
Specific purpose
in relation to the modification of a motor vehicle, includes, but is not limited to, a modification for motor sport activities and for a person with a disability.
Technical Standard
means a Japanese domestic vehicle standard issued by the Japanese Ministry of Land, Infrastructure and Transport and translated into, and published in, English by the Japan Automobile Standards Internationalization Center (JASIC) in the Automobile Type Approval Handbook for Japanese Certification.
UN/ECE
is an abbreviation for a regulation of the United Nations Economic Commission for Europe.
Vehicle
means a contrivance equipped with wheels, tracks, or revolving runners on which it moves or is moved; and includes a hovercraft, a skateboard, in-line skates and roller-skates; but does not include:
  • (a) a perambulator or pushchair;
  • (b) a shopping or sporting trundler not propelled by mechanical power;
  • (c) a wheelbarrow or hand-trolley;
  • (d) a child’s toy, including a tricycle and a bicycle, provided, in either case, no road wheel (including any tyre) has a diameter exceeding 355 mm;
  • (e) a pedestrian-controlled lawnmower;
  • (f) a pedestrian-controlled agricultural machine not propelled by mechanical power;
  • (g) an article of furniture;
  • (h) an invalid wheelchair not propelled by mechanical power;
  • (i) any other contrivance specified by any other rule not to be a vehicle for the purposes of this definition.
Vehicle inspector or inspecting organisation
has the same meaning as in Land Transport Rule: Vehicle Standards Compliance 2002.
Vehicle standard
means a technical specification with which a motor vehicle, its structure, systems, components or equipment must comply, and that is adopted by:
  • (a) the New Zealand Standards Council; or
  • (b) any international, national or regional organisation with functions similar to the New Zealand Standards Council.

 

Table A     Vehicle classes

Class Description
AA (Pedal cycle) A vehicle designed to be propelled through a mechanism solely by human power.
AB (Power-assisted pedal cycle) A pedal cycle to which is attached one or more auxiliary propulsion motors having a combined maximum power output not exceeding 200 watts.
LA (Moped with two wheels) A motor vehicle (other than a power-assisted pedal cycle) that:
  • (a) has two wheels; and
  • (b) either:
    • (i) has an engine cylinder capacity not exceeding 50 ml and a maximum speed not exceeding 50 km/h; or
    • (ii) has a power source other than a piston engine and a maximum speed not exceeding 50 km/h.
LB (Moped with three wheels) A motor vehicle (other than a power-assisted pedal cycle) that:
  • (a) has three wheels; and
  • (b) either:
    • (i) has an engine cylinder capacity not exceeding 50 ml and a maximum speed not exceeding 50 km/h; or
    • (ii) has a power source other than a piston engine and a maximum speed not exceeding 50 km/h.
LB 1 A Class LB motor vehicle that has one wheel at the front and two wheels at the rear.
LB 2 A Class LB motor vehicle that has two wheels at the front and one wheel at the rear.
LC (Motorcycle) A motor vehicle that:
  • (a) has two wheels; and
  • (b) either:
    • (i) has an engine cylinder capacity exceeding 50 ml; or
    • (ii) has a maximum speed exceeding 50 km/h.
LD (Motorcycle and side-car) A motor vehicle that:
  • (a) has three wheels asymmetrically arranged in relation to the longitudinal median axis; and
  • (b) either:
    • (i) has an engine cylinder capacity exceeding 50 ml; or
    • (ii) has a maximum speed exceeding 50 km/h.
Side-car A car, box, or other receptacle attached to the side of a motor cycle and supported by a wheel.
LE (Motor tri-cycle) A motor vehicle that:
  • (a) has three wheels symmetrically arranged in relation to the longitudinal median axis; and
  • (b) has a gross vehicle mass not exceeding one tonne; and
  • (c) either:
    • (i) has an engine cylinder capacity exceeding 50 ml; or
    • (ii) has a maximum speed exceeding 50 km/h.
LE 1 A Class LE motor vehicle that has one wheel at the front and two wheels at the rear.
LE 2 A Class LE motor vehicle that has two wheels at the front and one wheel at the rear.
Passenger vehicle A motor vehicle that:
  • (a) is constructed primarily for the carriage of passengers; and
  • (b) either:
    • (i) has at least four wheels; or
    • (ii) has three wheels and a gross vehicle mass exceeding one tonne.
MA (Passenger car)
A passenger vehicle (other than a Class MB or Class MC vehicle) that has not more than nine seating positions (including the driver's seating position).
MB (Forward control passenger vehicle)
A passenger vehicle (other than a Class MC vehicle):
  • (a) that has not more than nine seating positions (including the driver's seating position); and
  • (b) in which the centre of the steering wheel is in the forward quarter of the vehicle's total length.
MC (Off-road passenger vehicle)
A passenger vehicle, designed with special features for off-road operation, that has not more than nine seating positions (including the driver's seating position), and that:
  • (a) has four-wheel drive; and
  • (b) has at least four of the following characteristics when the vehicle is unladen on a level surface and the front wheels are parallel to the vehicle's longitudinal centre-line and the tyres are inflated to the vehicle manufacturer's recommended pressure:
    • (i) an approach angle of not less than 28 degrees;
    • (ii) a breakover angle of not less than 14 degrees;
    • (iii) a departure angle of not less than 20 degrees;
    • (iv) a running clearance of not less than 200 mm;
    • (v) a front-axle clearance, rear-axle clearance, or suspension clearance of not less than 175 mm.
Omnibus A passenger vehicle that has more than nine seating positions (including the driver's seating position). An omnibus comprising two or more non-separable but articulated units shall be considered as a single vehicle.
MD (Light omnibus) An omnibus that has a gross vehicle mass not exceeding 5 tonnes.
MD 1 An omnibus that has a gross vehicle mass not exceeding 3.5 tonnes and not more than 12 seats.
MD 2 An omnibus that has a gross vehicle mass not exceeding 3.5 tonnes and more than 12 seats.
MD 3 An omnibus that has a gross vehicle mass exceeding 3.5 tonnes but not exceeding 4.5 tonnes.
MD 4 An omnibus that has a gross vehicle mass exceeding 4.5 tonnes but not exceeding 5 tonnes.
ME (Heavy omnibus) An omnibus that has a gross vehicle mass exceeding 5 tonnes.
Goods vehicle A motor vehicle that:
  • (a) is constructed primarily for the carriage of goods; and
  • (b) either:
    • (i) has at least four wheels; or
    • (ii) has three wheels and a gross vehicle mass exceeding one tonne.
For the purpose of this description:
  • (a) a vehicle that is constructed for both the carriage of goods and passengers shall be considered primarily for the carriage of goods if the number of seating positions multiplied by 68 kg is less than 50% of the difference between the gross vehicle mass and the unladen mass;
  • (b) the equipment and installations carried on special purpose vehicles not designed for the carriage of passengers shall be considered to be goods;
  • (c) a goods vehicle that has two or more non-separable but articulated units shall be considered to be a single vehicle.
NA (Light goods vehicle) A goods vehicle that has a gross vehicle mass not exceeding 3.5 tonnes.
NB (Medium goods vehicle) A goods vehicle that has a gross vehicle mass exceeding 3.5 tonnes but not exceeding 12 tonnes.
NC (Heavy goods vehicle) A goods vehicle that has a gross vehicle mass exceeding 12 tonnes.
Trailer A vehicle without motive power that is constructed for the purpose of being drawn behind a motor vehicle.
TA (Very light trailer) A single-axled trailer that has a gross vehicle mass not exceeding 0.75 tonnes.
TB (Light trailer) A trailer (other than a Class TA trailer) that has a gross vehicle mass not exceeding 3.5 tonnes.
TC (Medium trailer) A trailer that has a gross vehicle mass exceeding 3.5 tonnes but not exceeding 10 tonnes.
TD (Heavy trailer) A trailer that has a gross vehicle mass exceeding 10 tonnes.

 

Land Transport Rule - Seats and Seat Anchorages 2002 - Rule 32004
Land Transport Safety Authority of New Zealand, Te Mana Marutau Waka Whenua o Aotearoa