EN ISO 3449 Earth-Moving Machinery - Protective Structures Against Falling Objects - Laboratory Tests and Performance Requirements

The standard “EN ISO 3449 Earth-moving machinery - Protective structures against falling objects - Laboratory tests and performance requirements”, which has its origins in a European standard and was subsequently published by the International Organization for Standardization (ISO), describes laboratory tests to measure the structural characteristics of falling object protection structures designed for use on ride-on earth-moving machinery, as defined in the standard “ISO 6165 Earth-moving machinery - Basic types - Definition and vocabulary”, and gives performance requirements in a representative test.

This standard applies to both falling object protection structures provided as an integral part of the machine and those provided separately for attachment to the machine. However, this standard is not intended to apply to falling object protection structures designed for use on landfill compactors, excavators, rollers, trenchers, pipelayers, as additional seats for the operation of an attachment (e.g. attachment excavator) or on machines with a power rating of less than 15 kW. This standard may be used to provide guidance to manufacturers of rollover or falling object protection structures when it is decided to provide such protection for these or other machines for a particular application.

For the purposes of this standard, the following terms and definitions apply:

• A falling object protection structure is a system of structural elements arranged to provide reasonable protection to operators from falling objects (trees, rocks, small concrete blocks, hand tools, and the like).
• A rollover protection structure is a system of structural members whose primary purpose is to reduce the likelihood that an operator wearing a seat belt will be crushed if the machine rolls over. Structural members include any subframes, brackets, mounts, sockets, bolts, pins, suspensions or flexible shock absorption used to secure the system to the machine frame, but excludes mounting provisions integral to the machine frame.
• The volume limiting the deviation is the orthogonal approximation of a large male seated operator wearing normal clothing and a hard hat.
• Level I impact protection is rated for impact resistance to protect from small falling objects (e.g. bricks, small concrete blocks, hand tools) encountered in operations such as highway maintenance, landscaping and other construction site services.
• Level II impact protection is impact resistance for protection from heavy falling objects (e.g. trees, rocks) for machines used in construction site clearing, overhead demolition or forestry.
• Representative testing is the testing of a sample whose material, size and processing requirements are specific to the production falling object protection structure.

The falling object protection structure can be integrated into the operator cabin structure. This test procedure usually destroys the falling object protection structure assembly because permanent deformation occurs in the structure and may not be able to reproduce structural deformations due to the change in the actual impact of falling objects. Two levels of performance criteria are specified for impact protection depending on the end use of the machine:

• Level I: Protection against impact from a round test object dropped from a height sufficient to develop an energy of 1 J.
• Level II: Protection against impact from a cylindrical test object dropped from a height sufficient to develop an energy of 11 600 J

The drop height of the test object is defined as a function of its mass as shown in the figure given in the standard. A falling object protection structure meeting these criteria will not provide crushing protection in all situations where the machine may be hit from above, but it is expected to provide protection against puncture under the specified conditions.

When performing tests, the falling object protection structure should be attached to the machine structure as in the actual machine use. Although a complete machine is not required, the part where the falling object protection structure is mounted should be the same as the actual structure and the vertical stiffness of the test bed should not be less than that of an actual machine according to this standard. Falling object protection structure mounted on the machine

For a falling object protection structure mounted on a machine:

• The machine can be supplied with equipment or attachments specified by the manufacturer.
• All ground contact tools must be in their normal carrying position.
• All suspension systems, including pneumatic tires, must be adjusted to their working levels and variable suspensions must be in their maximum stiffness range.
• All cabin elements, such as windows, normally removable panels or non-structural fittings, should be removed so that they do not contribute to the durability of the falling object containment structure.

Our organization, which has been trying to support businesses from every sector with its testing, measurement, analysis and evaluation studies carried out in a wide range for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services in accordance with the "EN ISO 3449 Earth moving machines - Protective structures against falling objects - Laboratory tests and performance requirements" standard are also provided to businesses.