Table 4:

Aggregation of Several Weights Lifted by a Worker During a Shift in Five WTCs and Computation of Correspondent Lifting Frequency: Example for Weights Ranging From 5 to 15 kg and for a Lifting Duration of 300 Min in a Shift

		Resulting Aggregated WTCs
Weight (kg)	No. of Objects Lifted per Shift by a Worker	Cat. No.	From	To	No. of Objects in Category	Average Weight (for the Category)	Percent Objects in Category	Overall and Partial Frequencies (Lifts/Min) (Referred to 300 Min Lifting Duration)
5	100
6	80	1	5.0	6.0	180	5.4	31.0%	0.60
7	70	2	7.0	8.0	170	7.6	29.3%	0.57
8	100	3	9.0	10.0	110	9.5	19.0%	0.36
9	50	4	11.0	12.0	90	11.6	15.5%	0.30
10	60	5	13.0	15.0	30	13.7	5.2%	0.10
11	40							1.93 (overall)
12	50
13	15
14	10
15	5
Total	580
Min. Weight Value (a)		Max. Weight Value (b)			Difference (b – a) = c			Weight Δ (for 5 Categories)
5		15			10			2