Zephyr: A High Altitude Long Endurance Unmanned Air Vehicle ...

The NIOSH have devised an equation that estimates the maximum load that the top90% of men (and the top 75% of women) can lift in accordance to long-term safety.The NIOSH lifting equation takes into account the horizontal distance between theuser and the object being carried, the height above ground from which the lift starts,the height moved during the lift, the twisting required by the user, the frequency ofthe action and the quality of the grip.Each variable has its own ‘multiplier’ which is dependent on the actual value and thenread from the NIOSH lifting tables. The product of all the multipliers together with alifting constant is calculated, producing an estimate for the maximum load the usershould lift.The NIOSH lifting equation is given below, where L is the maximum lifting weight.L = hm1 . vm2 . dm3 . tm4 . fm5 . gm6 . cThe six variables and their meanings are shown in table 1.Variable Description MultiplierH (cm)V (cm)Horizontal distance betweenspine and handsVertical distance fromground to object at start oflifthm1vm232