Requirements for finger entrapment in European safety ... - ANEC

Figure 1: The length of full middle finger, the finger tip (tip to distal joint) and the distal to middle
joint for USA male and female children in millimeters (Snyder, 1977)
Finger length shows a linear growth, therefore it is possible to develop a regression model to be able to
provide an estimate of the length of the finger tip for children younger than 2.5 years. There are two ways
to compute these values, which also allow the data to be validated.
Method 1 uses the change in the full finger length between each subsequent age group (i.e. the growth)
for children aged 0-42 months (using data from Snyder 1977) and applies this difference to the finger tip.
This is based on the assumption that growth in the overall finger length will be reflected in the same rate
of growth in the finger tip. For example, Table 13 shows that the growth in overall finger length between
0-3 and 4-6 months is 10.6. The results are shown in Table 13 (mean values), Table 14 (1 st percentile)
and Table 15 (99 th percentile).
Table 13: Calculation of mean MIDDLE FINGER tip length in mm (Method 1)
Age
Mean middle finger % growth in finger length Mean finger tip length
length
between age groups
0-3mo 29.5 10.6% 8.94
4-6 mo 33 8.3% 9.75
7-9 mo 36 0 9.75
10-12 mo 36 6.5% 10.43
13-18 mo 38.5 8.3% 11.38
19-24 mo 42 2.3% 11.65
2-2.5 yrs 43 5.5% 12.32
2.5-3.5yrs 45.5 5.2% 13
3.5-4.5 yrs 48 5.9% 13.39
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