AS ISO 2631.2:2014 pdf free download – Mechanical vibration and shock – Evaluation of human exposure to whole- body vibration
4.5.1 Vibration measurement
Vibration values should be determined by application of the methods given in ISO 2631-1. The vibration axis with the highest frequency-weighted vibration magnitude should be identified, and values obtained in this direction used for the evaluation.
In order to allow different kinds of future evaluation, it is recommended, wherever practicable, to use a measurement technique which records vibration time histories unweighted at least within the frequency range 1 Hz to 80 Hz.
4.5.2 Categories of source
For an evaluation, it is useful to categorize the vibration according to the major types of source which have been found in practice to give rise to adverse comments. Different magnitudes of vibration may be acceptable for the different categories. To establish international consistency of approach, the following categories are defined:
a) continuous or semi-continuous processes, e.g. industry;
b) permanent intermittent activities, e.g. traffic;
c) limited duration (non-permanent) activities, e.g. construction.
The categories have been selected to reflect the human perception of different vibration sources. They are not intended to be exclusive but to give guidance for the application of this part of ISO 2631.
4.6 Measuring instrumentation The requirements for measuring instrumentation, including tolerances, as given in ISO 8041 shall be followed.
5 Human responses to building vibration Experience in many countries has shown that adverse comments regarding building vibration in residential situations may arise from occupants of buildings when the vibration magnitudes are only slightly in excess of perception levels (see ISO 2631-1:1997, Annex C). In some cases complaints arise due to secondary effects associated with vibration, e.g. reradiated noise (see Annex B). In general, satisfactory magnitudes are likely to be related to general expectations and to economic, social and other environmental factors. They are not determined by factors such as short-term health hazards and working efficiency. Indeed, in practically all cases the magnitudes are such that fatigue directly induced by the motion is very unlikely. Situations exist where significantly higher vibration magnitudes can be tolerated, particularly for temporary disturbances and transient events. Examples of this are construction projects. Any startle factor can be reduced by a proper programme of public relations which may include announcements such as warning signals and/or concerning regularity of occurrence. Only in extremely rare cases should it be necessary to consult the criterion “health” as given in ISO 2631-1. For situations in which vibration occurs over an extended period, long-term familiarization may give rise to a change in adverse comment thresholds.