http://www.legislation.gov.uk/id/uksi/2005/1093/schedule/2

SCHEDULE 2Whole-Body Vibration

Part II-Exposure to vibration averaged over one week

The exposure to vibration averaged over one week (A(8)_week) is the total exposure occurring within a period of seven consecutive days, normalised to a reference duration of five 8-hour days (40 hours). It is ascertained using the formula:

{A (8)}_{w e e k} = \sqrt{\frac{1}{5} \sum_{j = 1}^{7} {A (8)}_{j}^{2}}

where:

A(8)j is the daily exposure for day j.