1.1 This document specifies, in accordance with ISO 10326-1:2016, a laboratory method for measuring and evaluating the effectiveness of the seat suspension in reducing the vertical whole-body vibration transmitted to the operator of earth-moving machines at frequencies between 1 Hz and 20 Hz. It also specifies acceptance criteria for application to seats on different machines.
1.2 This document is applicable to operator seats used on earth-moving machines as defined in ISO 6165.
1.3 This document defines the input spectral classes required for the following earth-moving machines. Each class defines a group of machines having similar vibration characteristics:
- rigid-frame dumpers >4 500 kg operating mass;
- articulated-frame dumpers;
- scrapers without axle or frame suspension;
- wheeled loaders >4 500 kg operating mass;
- wheeled dozers;
- soil compactors;
- backhoe loaders;
- crawler dumpers;
- crawler loaders;
- crawler-dozers ≤50 000 kg operating mass;
- compact dumpers ≤4 500 kg operating mass;
- wheeled compact loaders ≤4 500 kg operating mass;
- skid-steer loaders, wheeled ≤4 500 kg and tracked ≤6 000 kg operating mass.
1.4 The following machines impart sufficiently low vertical vibration inputs at frequencies between 1 Hz and 20 Hz to the seat during operation that these seats do not require suspension for the attenuation of transmitted vibration:
- excavators, including walking excavators and cable excavators;
- landfill compactors;
- non-vibratory rollers, except soil compactors;
- vibratory rollers, except soil compactors;
- horizontal directional drills (HDD).
1.5 The tests and criteria defined in this document are intended for operator seats used in earth-moving machines of conventional design.
NOTE Other tests can be appropriate for machines with design features that result in significantly different vibration characteristics.
1.6 Vibration which reaches the operator other than through the seat, for example that sensed by the operator's feet on the platform or control pedals or by the operator's hands on the steering-wheel, is not covered.
 For scrapers with suspension, either a seat with no suspension can be used, or one having a suspension with high damping.
 For crawler dozers greater than 50 000 kg, the seat performance requirements are suitably provided by a cushion type seat.
 For excavators, the predominant vibration is generally in the fore and aft (X) axis.