General Provisions

The following definitions shall be applied for the purpose of this annex:

The letter g means the standard acceleration of gravity; g equals 9.8 m/s2.

The word load, when used to describe a physical quantity to which units may be ascribed, signifies mass.

Maximum operating gross mass or Rating or R means the maximum allowable sum of the mass of the container and its cargo. The letter R is expressed in units of mass. Where the annexes are based on gravitational forces derived from this value, that force, which is an inertial force, is indicated as Rg.

Maximum permissible payload or P means the difference between maximum operating gross mass or rating and tare. The letter P is expressed in units of mass. Where the annexes are based on the gravitational forces derived from this value, that force, which is an inertial force, is indicated as Pg.

Tare means the mass of the empty container, including permanently affixed ancillary equipment.

Introduction

In setting the requirements of this annex, it is implicit that, in all phases of the operation of containers, the forces as a result of motion, location, stacking and gravitational effect of the loaded container and external forces will not exceed the design strength of the container. In particular, the following assumptions have been made:

(a) the container will so be restrained that it is not subjected to forces in excess of those for which it has been designed;

(b) the container will have its cargo stowed in accordance with the recommended practices of the trade so that the cargo does not impose upon the container forces in excess of those for which it has been designed.

Construction

1. A container made from any suitable material which satisfactorily performs the following tests without sustaining any permanent deformation or abnormality which would render it incapable of being used for its designed purpose shall be considered safe.

2. The dimensions, positioning and associated tolerances of corner fittings shall be checked having regard to the lifting and securing systems in which they will function.

Test loads and test procedures

Where appropriate to the design of the container, the following test loads and test procedures shall be applied to all kinds of containers under test:

TEST LOAD AND APPLIED FORCES | TEST PROCEDURES

1. LIFTING

The container, having the prescribed internal loading, shall be lifted in such a way that no significant acceleration forces are applied. After lifting, the container shall be suspended or supported for five minutes and then lowered to the ground.

(A) LIFTING FROM CORNER FITTINGS

Internal load: | (i) Lifting from top corner fittings:

A uniformly distributed load such that the sum of the mass of container and test load is equal to 2R. In the case of a tank container, when the test load of the internal load plus the tare is less than 2R, a supplementary load, distributed over the length of the tank, is to be added to the container. | Containers greater than 3,000 mm (10 ft.) (nominal) in length shall have lifting forces applied vertically at all four top corner fittings.

Containers of 3,000 mm (10 ft.) (nominal) in length nor less shall have lifting forces applied at all four top corner fittings, in such a way that the angle between each lifting device and the vertical shall be 30°.

Externally applied forces: | (ii) Lifting from bottom corner fittings:

Such as to lift the sum of a mass of 2R in the manner prescribed (under the heading TEST PROCEDURES). | Containers shall have lifting forces applied in such a manner that the lifting devices bear on the bottom corner fittings only. The lifting forces shall be applied at angles to the horizontal of: 30° for containers of length 12,000 mm (40 ft.) (nominal) or greater; 37° for containers of length 9,000 mm (30 ft.) (nominal) and up to but not including 12,000 mm (40 ft.) (nominal); 45° for containers of length 6,000 mm (20 ft.) (nominal) and up to but not including 9,000 mm (30 ft.) (nominal); 60° for containers of less than 6,000 mm (20 ft.) (nominal).

(B) LIFTING BY ANY OTHER ADDITIONAL METHODS

Internal load: | (i) Lifting from fork-lift pockets:

A uniformly distributed load such that the sum of the mass of container and test load is equal to 1.25R. | The container shall be placed on bars which are in the same horizontal plane, one bar being centred within each fork-lift pocket which is used for lifting the loaded container. The bars shall be of the same width as the forks intended to be used in the handling, and shall project into the fork pocket 75% of the length of the fork pocket.

Externally applied forces:

Such as to lift the sum of a mass of 1.25R in the manner prescribed (under the heading TEST PROCEDURES).

Internal load: | (ii) Lifting from grappler-arm positions:

A uniformly distributed load such that the sum of the mass of container and test load is equal to 1.25R. In the case of a tank container, when the test load of the internal load plus the tare is less than 1.25R, a supplementary load, distributed over the length of the tank, is to be added to the container. | The container shall be placed on pads in the same horizontal plane, one under each grappler-arm position. These pads shall be of the same sizes as the lifting area of the grappler arms intended to be used.

Externally applied forces:

Such as to lift the sum of a mass of 1.25R in the manner prescribed (under the heading TEST PROCEDURES).

iii) Other methods:

Where containers are designed to be lifted in the loaded condition by any method not mentioned in (A) or (B)(i) and (ii) they shall also be tested with the internal load and externally applied forces representative of the acceleration conditions appropriate to that method.

2. STACKING

1. For conditions of international transport where the maximum vertical acceleration varies significantly from 1.8 g and when the container is reliably and effectively limited to such conditions of transport, the stacking load may be varied by the appropriate ratio of acceleration.

2. On successful completion of this test, the container may be rated for the allowable superimposed static stacking load, which should be indicated on the Safety Approval Plate against the heading ALLOWABLE STACKING LOAD FOR 1.8 g (kg and lbs).

Internal load:

A uniformly distributed load such that the sum of the mass of container and test load is equal to 1.8R. Tank containers may be tested in the tare condition. | The container, having the prescribed INTERNAL LOADING, shall be placed on four level pads which are in turn supported on a rigid horizontal surface, one under each bottom corner fitting or equivalent corner structure. The pads shall be centralized under the fittings and shall be of approximately the same plan dimensions as the fittings.

Externally applied forces:

Such as to subject each of the four top corner fittings to a vertical downward force equal to 0.25 x 1.8 x the gravitational force of the allowable superimposed static stacking load. | Each EXTERNALLY APPLIED FORCE shall be applied to each of the corner fittings through a corresponding test corner fitting or through a pad of the same plan dimensions. The test corner fitting or pad shall be offset with respect to the top corner fitting of the container by 25 mm (1 in.) laterally and 38 mm (1½ in.) longitudinally.

3. CONCENTRATED LOADS

(a) On roof

Internal load:

None.

Externally applied forces:

A concentrated gravitational force of 300 kg (660 lbs) uniformly distributed over an area of 600 mm x 300 mm (24 in x 12 in). | The externally applied forces shall be applied vertically downwards to the outer surface of the weakest area of the roof of the container.

3. CONCENTRATED LOADS

(b) On floor

Internal load: | The test should be made with the container resting on four level supports under its four bottom corners in such a manner that the base structure of the container is free to deflect.