Porter, Mic

English

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Citation: Porter, Mic (2001) Getting stuck- the anthropometry of young children's fingers. In: Annual  
Conference of the Ergonomics Society, 10-12 April 2001, Royal Agricultural College, Cirencester. 
URL: 
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GETTING STUCK – THE ANTHROPOMETRY OF YOUNG 
CHILDREN’S FINGERS 
 
 
Mic L. Porter 
 
 
School of Design 
University of Northumbria at Newcastle 
Newcastle-upon-Tyne 
NE1 8ST 
mic.porter@unn.ac.uk 
 
 
 
An incident occurred in a “Community Infant School” when a child, aged 
3+, trapped a finger while playing with a water-bath.  The bath was found 
to conform to the relevant safety standards and this apparent 
incompatibility acted as the trigger for this study.  The study sought to 
obtain anthropometric data, graded by age, of the finger sizes to be found 
in children living in the North East and attending similar schools to the one 
which had experienced the incident.  This data is outlined and compared 
with various published sources.  Guidance is also given for Designers of 
consumer and other products with which young children might come into 
contact. 
 
 
Introduction and background 
 
A child attending a “Community Infant School” was able to trap a finger in the drain 
hole of the water-bath with which they had been playing.  This was, obviously 
distressing and painful for the child and of concern to the School.  The School referred 
the matter to the local Trading Standards Department which reported that the bath 
complied with the relevant safety standards.  As this was clearly an undesirable situation, 
an anthropometric data collection project was started. 
 
The finger length was measured, palm upward, with a metal ruler marked in half 
millimetres.  The larger finger joint diameters were measured with standard UK 
Jewellers ring “sizer” gauges and a special set made to extended the range downwards 
and thus accommodate the smallest fingers.  The traditional “sizers” are of known 
diameter and produced in steps of, approximately, 0.2 mm.  These will yield more 
precise data than would be collectable with the commonly used drilled (in 1 mm steps) 
plastic sheet.  Examples of the infant “sizers” are shown (overleaf) in Figure 1.  Further 
details of the measurements techniques adopted can be found in Porter (2000). 
 
The data reported in this paper has been revised from that reported previously (Porter 
2000) to include subjects from another geographical area and especially to enlarge the 
sample taken from the cohort of pupils who would, shortly, transfer, at 7+, to a 
“Community Junior School”.  
 
The “sizer” ring diameter recorded was the smallest through which the finger would, 
without the application of force, freely pass.  During the trial the child was instructed not 
to push or twist their fingers in an attempt to “make it fit”. The experimenter was also 
vigilant to ensure an unforced measurement and thus avoid the possibility of a trapped 
finger.  The diameter through which the finger would not pass (“just binds”) was taken to 
be one size smaller in diameter. 
 
 
Figure 1.  Examples of the “sizers” produced in the School of Design 
 
Three caveats to the study should be noted.  The sample, like the population in the 
North East was largely white and included only about 3% of visibly non European 
children.  Ethnic diversity issues have not, therefore, been investigated in this study. 
 
It should also be noted that fingers are ellipsoidal (not circular) in cross section and 
deformable soft tissue overlies the structure of the finger.  Thus care must be taken by a 
Designer considering non circular holes. 
 
The soft tissue of the finger does deform when forced through a tight but thin hole 
and, for reasons not yet understood by the author, would appear to “flow” more easily 
when the ring “sizer” is inserted than when it is removed.  No fingers were trapped 
during the data collection but the possibility was considered and removal strategies 
planned.  It is expected that data collected with a drilled thin plastic sheet would have 
similar risks. 
Results 
 
The anthropometric data collected is available from the author.  This database consists of 
finger lengths and joint diameters for children aged 6 months to 7½ years in six month 
sets.  The data referred to is presented, in table 1. 
 
Table 1. Distal joint diameter and (aged 7 only) finger length; both sexes in mm 
Mean(SD) Thumb 
Index 
Finger 
Middle 
Finger 
Ring 
Finger 
Little 
Finger 
Criteria 
       
6 - <8 mth. 
n = 20 
10.1 (1.0) 7.7 (0.4) 8.1 (0.4) 7.8 (0.4) 7.1 (0.3) 
“just 
binds” 
30 - <36 mth. 
n = 20 
12.6 (0.4) 10.0 (0.6) 10.3 (0.7) 10.0 (0.5) 8.8 (0.3) 
“just 
passes” 
3½ - <4 yrs. 
N = 51 
13.3 (0.8) 10.5 (1.1) 10.7 (0.8) 10.3 (0.8) 9.1 (0.6) 
“just 
binds” 
7 - <7½ yrs. 
n = 31 
15.6 (1.0) 12.2 (0.9) 12.4 (0.8) 11.7 (0.7) 10.7 (0.7) 
“just 
passes” 
 43.6 (4.2) 51.7 (3.2) 56.7 (3.9) 51.1 (4.6) 43.0 (3.9)  
 
 
Discussion and guidance for designers 
 
Nearly twenty five years ago in the USA Snyder et al collected and published two sets 
(1975 and 1977) of anthropometric data for infants and children.  Comparison of the data 
for the middle finger shows that the latter sample generally found slightly smaller values.  
The data published by the German Standards Institute (DIN 1981) is, where comparisons 
are possible, slightly larger than Snyder et al samples.  However, direct comparison is 
impossible because of variations in the age bands reported.  Norris and Wilson (1995) 
also quote limited details from Steenbekkers (1993) who reports longer, but much 
thinner fingers than the other samples.  
 
In comparison to these data (table 2 overleaf) this survey is also in general agreement 
albeit with finger lengths generally larger and diameters generally smaller. Again, 
however, precise comparisons are often impossible due to the differences in age 
categories.  This sample, however, does contain a greater quantity of hand 
anthropometric data collected from a sample of children under 7½ years old. 
 
The “European Normalised” British Standard relevant to the safety of toys (BS 
1998) has developed from BS 5665 (BS 1988) and the sections referring to holes are, 
essentially, unchanged.  The test appears to be mainly concerned with preventing the 
child pushing their finger through the hole and coming into contact with something 
undesirable rather than simply becoming stuck.  The Standards specify an “articulated 
accessibility probe” which comes in two sizes for products to be used by children under 
36 months and another for between 36 months and 14 years.  The Standard requires that 
both probes should be applied if the product will be used by all children under 14.  
Table 2. Comparative data (both sexes) from published sources (mm) 
Dimension and 
source 
Thumb 
Index 
finger 
Middle 
finger 
Ring 
finger 
Little 
finger 
      
Snyder et al (1975)      
7 - 9 mth.  Length 
distal joint diameter 
  36 (4) 
8.4 (0.5) 
 30 (5) 
7.4 (0.5) 
31 - 36 mth.  Length 
distal joint diameter 
  45 (4) 
10 (0.7) 
 33 (3) 
8.6 (0.5) 
79 - 84 mth.  Length 
distal joint diameter 
  56 (4) 
11.9 (0.8) 
 41 (04) 
10.1(0.7) 
8 years  Length 
distal joint diameter 
  58 (4) 
12.2 (0.8) 
 43 (4) 
10.3 (0.7) 
      
Snyder et al (1977)      
6 - 8 mth.  Length 9.9 (0.7)  8.3 (0.7)   
2 - 3½ yr.  Length 
distal joint diameter 
36 (4) 
12.4 (0.9) 
41 (4) 
9.6 (0.6) 
44 (4) 
9.9 (0.6) 
  
6½ - 7½ yr.  Length 
distal joint diameter 
47 (4) 
15.0 (1.0) 
52 (3) 
11.7 (0.8) 
58 (4) 
12.0 (0.9) 
  
      
DIN (1981) (All standard deviations estimated from range data) 
3 years  Length 37 (2.1) 42 (2.4)  45 (2.7) 36 (2.7) 
7 years  Length 46 (3.3) 54 (3.3)  55 (3.3) 44 (3.6) 
8 years  Length 47 (3.6) 55 (3.9)  57 (3.9) 45 (3.9) 
      
Steenbekkeers (1993) (Standard deviations for diameter estimated from range data) 
3 years  Length   49 (4)   
7 years  Length   59 (4)   
0 - 2 mth. distal joint     6.5 (1.0) 
3 - 5 yrs. distal joint     6.6 (0.5) 
6 - 8 yrs. distal joint     7 (0.3) 
 
The end of the smaller probe is 5.6 mm in diameter and 44 mm long.  This would 
safely satisfy the data collected in this study.  However, it is clear that the larger probe 
does expose children to the risk of trapped fingers if they are only a little older than 3 
years but intent on “exploring”.  The child whose incident triggered this study fell into 
this category.  For the older age group the data is 8.6 mm diameter and 57.9 mm long.  
The length standard is acceptable given that children whose fingers are this long will be 
prevented from insertion due to the hole diameter. 
 
However, the Standard will expose some children to the risk of trapping fingers.  For 
example, the data given in table 1 for mean and standard deviations of the 3½-4 year old 
child would imply approximately 4% of children risk jamming their Index finger and 
about 1.75% their ring finger into a hole that would satisfy the Standard.  Of course, the 
risk of being able to jam the little finger is even greater; approximately 20 of that 
population. 
 
There are two approaches to ensuring that fingers cannot get stuck in orifices or holes.  
The Index is to ensure that the hole is too small for the finger to penetrate and thus the 
critical dimension is for the youngest child’s smallest finger.  The data collected suggests 
that the critical hole diameter should be less than 5.9 mm (mean minus four standard 
deviations).  Alternatively a less secure/satisfactory standard would be 6.2 mm diameter 
(mean minus three standard deviations). (Table 3, below) 
 
Table 3. Data calculated from the means and standard deviations (SD) 
 Thumb 
Index 
Finger 
Middle 
Finger 
Ring 
Finger 
Little 
Finger 
      
6 - <8 months      
Mean - 3SD 7.1 mm 6.5 mm 6.9 mm 6.6 mm 6.2mm 
Mean - 4SD 6.1 mm 6.1 mm 6.5 mm 6.2 mm 5.9mm 
30 - <36 months       
Mean + 3SD 13.8 mm 11.8 mm 12.4 mm 11.5 mm 9.7 mm 
Mean + 4SD 14.2 mm 12.4 mm 13.1 mm 12.0 mm 10.0 mm 
7 - 7½ years      
Mean + 3SD 18.6 mm 14.9 mm 14.8 mm 13.8 mm 12.8 mm 
Mean + 4SD 19.6 mm 15.8 mm 15.6 mm 14.5 mm 13.5 mm 
 
The second, alternative, approach is to ensure that any finger (or the thumb) can pass 
freely through the hole without the risk of becoming trapped or of scratching against the 
edge.  This general standard would need to be based upon the largest diameter finger on 
the largest child to be considered.  Thus the critical dimension would be the mean plus 
three standard deviations or the much safer plus four standard deviations.  For small 
items the general guidance is for the under 36 months. For this group a hole diameter of 
14.2 mm or 13.8 mm respectively is implied.  However, a hole of this diameter will have 
the potential to trap the fingers and thumbs of some of the older children.  In the case of 
the 7 -7½ age group a 14.2 mm diameter hole can be calculated to be, approximately, 
equivalent to a 8th percentile thumb joint and thus a potential trap.  The 13.8 mm hole 
could also trap fingers.  The diameter of the desirable “clearance” hole for all children (7 
-7½) may be calculated to be 18.6 mm (mean plus 3SD) or 19.6 mm (mean plus 4SD).  
 
In the case of this second criterion, a further factor may need consideration from the 
point of view of safety.  Is it possible for a finger inserted in the hole to come to harm 
from what is behind; either by physical contact or by sufficient proximity to an electrical 
source that a spark may jump the remaining gap.  The length of fingers for the 7 -7½ age 
group is given in table 1.  The longest finger is the middle and consideration of which 
suggests a clearance between the base of the finger and the risk should be 68.4 mm 
(mean plus 3SD) or the safer 72.3 mm (mean plus 4SD).  
 
Conclusions 
 
Children whose age is near to the bottom of the 36 month – 14 year range could, 
potentially, get their fingers caught in holes that met the Standards for which revision 
would, thus, be desirable.  A trapped finger is unlikely to be “life threatening” but will be 
distressing and, potentially painful.   
 
The mechanism by which soft tissue can roll and “squirm” through very thin objects, 
such as used in this and other studies, increases this risk and should be investigated 
further.  It would appear that the flexibility of the soft tissue is different in each direction, 
generally it is easier to force the finger through the hole than it is to extract it!  
 
The data collected in this study is more complete that that published in other sources 
and thus should aid the Designer, especially those working on consumer products.  
 
 
Acknowledgements 
 
Acknowledgement must be made to all the children who agreed to be measured, to their 
parents/guardians who gave the required permission and to the staff of the schools and 
nurseries involved in this study.  To Derek Anderson, Jewellery Technician, within the 
School of Design who expertly produced the infant ring “sizers” essential to this data 
collection exercise and to Katherine Johnston who under took the pilot project. 
 
 
References 
 
BS, 1989, BS 5665: Safety of Toys Part 1,Specification for Mechanical and Physical 
Properties, (British Standards, London) 
BS, 1998, EN BS 71-1: Safety of Toys Part 1, Mechanical and Physical Properties, 
(British Standards, London) 
DIN, 1981, DIN 33402:Body dimensions of people, June 1981, (Deutsches Institut fur 
Normung (DIN) e V, Berlin) (Quoted in Norris and Wilson 1995) 
Norris B. and Wilson J.R., 1995, Childata, URN 95/681, (Consumer Safety Unit, 
Department of Trade, London) 
Snyder, R.G. Spencer M.L. Owings C.L. and Schneider L.W. 1975, Anthropometry of 
US  Infants and Children (SP394), (Society of Automotive Engineers(SAE), 
Washington, DC) 
Synder, R.G., Schneider L.W., Owings C.L., Golomb D.H. and Schork M.A. 1977, 
Anthropometry of infants, children and youths to age 18 for product safety design, 
Report# UM-HSRI-77, (Consumer Product Safety Commission, Washington, DC) 
(Quoted in Norris and Wilson 1995) 
Porter, M.L. 2000, The Anthropometry of the fingers of Children, In the proceedings of 
the IEA2000/HFES Congress, San Diego, (Human Factors and Ergonomics Society, 
Santa Monica) 
Steenbekkers, L.P.A., 1993, Child development design implication & accident 
prevention, No 1 in Physical Ergonomics Series, (Delft University of Technology 
(TU Delft), The Netherlands)  


Getting stuck- the anthropometry of young children's fingers

Northumbria University Research Portal

 GETTING STUCK – THE ANTHROPOMETRY OF YOUNG CHILDREN’S FINGERS   Mic L. Porter   School of Design University of Northumbria at Newcastle Newcastle-upon-Tyne NE1 8ST mic.porter@unn.ac.uk    An incident occurred in a “Community Infant School” when a child, aged 3+, trapped a finger while playing with a water-bath.  The bath was found to conform to the relevant safety standards and this apparent incompatibility acted as the trigger for this study.  The study sought to obtain anthropometric data, graded by age, of the finger sizes to be found in children living in the North East and attending similar schools to the one which had experienced the incident.  This data is outlined and compared with various published sources.  Guidance is also given for Designers of consumer and other products with which young children might come into contact.   Introduction and background  A child attending a “Community Infant School” was able to trap a finger in the drain hole of the water-bath with which they had been playing.  This was, obviously distressing and painful for the child and of concern to the School.  The School referred the matter to the local Trading Standards Department which reported that the bath complied with the relevant safety standards.  As this was clearly an undesirable situation, an anthropometric data collection project was started.  The finger length was measured, palm upward, with a metal ruler marked in half millimetres.  The larger finger joint diameters were measured with standard UK Jewellers ring “sizer” gauges and a special set made to extended the range downwards and thus accommodate the smallest fingers.  The traditional “sizers” are of known diameter and produced in steps of, approximately, 0.2 mm.  These will yield more precise data than would be collectable with the commonly used drilled (in 1 mm steps) plastic sheet.  Examples of the infant “sizers” are shown (overleaf) in Figure 1.  Further details of the measurements techniques adopted can be found in Porter (2000).  The data reported in this paper has been revised from that reported previously (Porter 2000) to include subjects from another geographical area and especially to enlarge the sample taken from the cohort of pupils who would, shortly, transfer, at 7+, to a “Community Junior School”.   The “sizer” ring diameter recorded was the smallest through which the finger would, without the application of force, freely pass.  During the trial the child was instructed not to push or twist their fingers in an attempt to “make it fit”. The experimenter was also vigilant to ensure an unforced measurement and thus avoid the possibility of a trapped finger.  The diameter through which the finger would not pass (“just binds”) was taken to be one size smaller in diameter.   Figure 1.  Examples of the “sizers” produced in the School of Design  Three caveats to the study should be noted.  The sample, like the population in the North East was largely white and included only about 3% of visibly non European children.  Ethnic diversity issues have not, therefore, been investigated in this study.  It should also be noted that fingers are ellipsoidal (not circular) in cross section and deformable soft tissue overlies the structure of the finger.  Thus care must be taken by a Designer considering non circular holes.  The soft tissue of the finger does deform when forced through a tight but thin hole and, for reasons not yet understood by the author, would appear to “flow” more easily when the ring “sizer” is inserted than when it is removed.  No fingers were trapped during the data collection but the possibility was considered and removal strategies planned.  It is expected that data collected with a drilled thin plastic sheet would have similar risks. Results  The anthropometric data collected is available from the author.  This database consists of finger lengths and joint diameters for children aged 6 months to 7½ years in six month sets.  The data referred to is presented, in table 1.  Table 1. Distal joint diameter and (aged 7 only) finger length; both sexes in mm Mean(SD) Thumb Index Finger Middle Finger Ring Finger Little Finger Criteria        6 - <8 mth. n = 20 10.1 (1.0) 7.7 (0.4) 8.1 (0.4) 7.8 (0.4) 7.1 (0.3) “just binds” 30 - <36 mth. n = 20 12.6 (0.4) 10.0 (0.6) 10.3 (0.7) 10.0 (0.5) 8.8 (0.3) “just passes” 3½ - <4 yrs. N = 51 13.3 (0.8) 10.5 (1.1) 10.7 (0.8) 10.3 (0.8) 9.1 (0.6) “just binds” 7 - <7½ yrs. n = 31 15.6 (1.0) 12.2 (0.9) 12.4 (0.8) 11.7 (0.7) 10.7 (0.7) “just passes”  43.6 (4.2) 51.7 (3.2) 56.7 (3.9) 51.1 (4.6) 43.0 (3.9)    Discussion and guidance for designers  Nearly twenty five years ago in the USA Snyder et al collected and published two sets (1975 and 1977) of anthropometric data for infants and children.  Comparison of the data for the middle finger shows that the latter sample generally found slightly smaller values.  The data published by the German Standards Institute (DIN 1981) is, where comparisons are possible, slightly larger than Snyder et al samples.  However, direct comparison is impossible because of variations in the age bands reported.  Norris and Wilson (1995) also quote limited details from Steenbekkers (1993) who reports longer, but much thinner fingers than the other samples.   In comparison to these data (table 2 overleaf) this survey is also in general agreement albeit with finger lengths generally larger and diameters generally smaller. Again, however, precise comparisons are often impossible due to the differences in age categories.  This sample, however, does contain a greater quantity of hand anthropometric data collected from a sample of children under 7½ years old.  The “European Normalised” British Standard relevant to the safety of toys (BS 1998) has developed from BS 5665 (BS 1988) and the sections referring to holes are, essentially, unchanged.  The test appears to be mainly concerned with preventing the child pushing their finger through the hole and coming into contact with something undesirable rather than simply becoming stuck.  The Standards specify an “articulated accessibility probe” which comes in two sizes for products to be used by children under 36 months and another for between 36 months and 14 years.  The Standard requires that both probes should be applied if the product will be used by all children under 14.  Table 2. Comparative data (both sexes) from published sources (mm) Dimension and source Thumb Index finger Middle finger Ring finger Little finger       Snyder et al (1975)      7 - 9 mth.  Length distal joint diameter   36 (4) 8.4 (0.5)  30 (5) 7.4 (0.5) 31 - 36 mth.  Length distal joint diameter   45 (4) 10 (0.7)  33 (3) 8.6 (0.5) 79 - 84 mth.  Length distal joint diameter   56 (4) 11.9 (0.8)  41 (04) 10.1(0.7) 8 years  Length distal joint diameter   58 (4) 12.2 (0.8)  43 (4) 10.3 (0.7)       Snyder et al (1977)      6 - 8 mth.  Length 9.9 (0.7)  8.3 (0.7)   2 - 3½ yr.  Length distal joint diameter 36 (4) 12.4 (0.9) 41 (4) 9.6 (0.6) 44 (4) 9.9 (0.6)   6½ - 7½ yr.  Length distal joint diameter 47 (4) 15.0 (1.0) 52 (3) 11.7 (0.8) 58 (4) 12.0 (0.9)         DIN (1981) (All standard deviations estimated from range data) 3 years  Length 37 (2.1) 42 (2.4)  45 (2.7) 36 (2.7) 7 years  Length 46 (3.3) 54 (3.3)  55 (3.3) 44 (3.6) 8 years  Length 47 (3.6) 55 (3.9)  57 (3.9) 45 (3.9)       Steenbekkeers (1993) (Standard deviations for diameter estimated from range data) 3 years  Length   49 (4)   7 years  Length   59 (4)   0 - 2 mth. distal joint     6.5 (1.0) 3 - 5 yrs. distal joint     6.6 (0.5) 6 - 8 yrs. distal joint     7 (0.3)  The end of the smaller probe is 5.6 mm in diameter and 44 mm long.  This would safely satisfy the data collected in this study.  However, it is clear that the larger probe does expose children to the risk of trapped fingers if they are only a little older than 3 years but intent on “exploring”.  The child whose incident triggered this study fell into this category.  For the older age group the data is 8.6 mm diameter and 57.9 mm long.  The length standard is acceptable given that children whose fingers are this long will be prevented from insertion due to the hole diameter.  However, the Standard will expose some children to the risk of trapping fingers.  For example, the data given in table 1 for mean and standard deviations of the 3½-4 year old child would imply approximately 4% of children risk jamming their Index finger and about 1.75% their ring finger into a hole that would satisfy the Standard.  Of course, the risk of being able to jam the little finger is even greater; approximately 20 of that population.  There are two approaches to ensuring that fingers cannot get stuck in orifices or holes.  The Index is to ensure that the hole is too small for the finger to penetrate and thus the critical dimension is for the youngest child’s smallest finger.  The data collected suggests that the critical hole diameter should be less than 5.9 mm (mean minus four standard deviations).  Alternatively a less secure/satisfactory standard would be 6.2 mm diameter (mean minus three standard deviations). (Table 3, below)  Table 3. Data calculated from the means and standard deviations (SD)  Thumb Index Finger Middle Finger Ring Finger Little Finger       6 - <8 months      Mean - 3SD 7.1 mm 6.5 mm 6.9 mm 6.6 mm 6.2mm Mean - 4SD 6.1 mm 6.1 mm 6.5 mm 6.2 mm 5.9mm 30 - <36 months       Mean + 3SD 13.8 mm 11.8 mm 12.4 mm 11.5 mm 9.7 mm Mean + 4SD 14.2 mm 12.4 mm 13.1 mm 12.0 mm 10.0 mm 7 - 7½ years      Mean + 3SD 18.6 mm 14.9 mm 14.8 mm 13.8 mm 12.8 mm Mean + 4SD 19.6 mm 15.8 mm 15.6 mm 14.5 mm 13.5 mm  The second, alternative, approach is to ensure that any finger (or the thumb) can pass freely through the hole without the risk of becoming trapped or of scratching against the edge.  This general standard would need to be based upon the largest diameter finger on the largest child to be considered.  Thus the critical dimension would be the mean plus three standard deviations or the much safer plus four standard deviations.  For small items the general guidance is for the under 36 months. For this group a hole diameter of 14.2 mm or 13.8 mm respectively is implied.  However, a hole of this diameter will have the potential to trap the fingers and thumbs of some of the older children.  In the case of the 7 -7½ age group a 14.2 mm diameter hole can be calculated to be, approximately, equivalent to a 8th percentile thumb joint and thus a potential trap.  The 13.8 mm hole could also trap fingers.  The diameter of the desirable “clearance” hole for all children (7 -7½) may be calculated to be 18.6 mm (mean plus 3SD) or 19.6 mm (mean plus 4SD).   In the case of this second criterion, a further factor may need consideration from the point of view of safety.  Is it possible for a finger inserted in the hole to come to harm from what is behind; either by physical contact or by sufficient proximity to an electrical source that a spark may jump the remaining gap.  The length of fingers for the 7 -7½ age group is given in table 1.  The longest finger is the middle and consideration of which suggests a clearance between the base of the finger and the risk should be 68.4 mm (mean plus 3SD) or the safer 72.3 mm (mean plus 4SD).   Conclusions  Children whose age is near to the bottom of the 36 month – 14 year range could, potentially, get their fingers caught in holes that met the Standards for which revision would, thus, be desirable.  A trapped finger is unlikely to be “life threatening” but will be distressing and, potentially painful.    The mechanism by which soft tissue can roll and “squirm” through very thin objects, such as used in this and other studies, increases this risk and should be investigated further.  It would appear that the flexibility of the soft tissue is different in each direction, generally it is easier to force the finger through the hole than it is to extract it!   The data collected in this study is more complete that that published in other sources and thus should aid the Designer, especially those working on consumer products.    Acknowledgements  Acknowledgement must be made to all the children who agreed to be measured, to their parents/guardians who gave the required permission and to the staff of the schools and nurseries involved in this study.  To Derek Anderson, Jewellery Technician, within the School of Design who expertly produced the infant ring “sizers” essential to this data collection exercise and to Katherine Johnston who under took the pilot project.   References  BS, 1989, BS 5665: Safety of Toys Part 1,Specification for Mechanical and Physical Properties, (British Standards, London) BS, 1998, EN BS 71-1: Safety of Toys Part 1, Mechanical and Physical Properties, (British Standards, London) DIN, 1981, DIN 33402:Body dimensions of people, June 1981, (Deutsches Institut fur Normung (DIN) e V, Berlin) (Quoted in Norris and Wilson 1995) Norris B. and Wilson J.R., 1995, Childata, URN 95/681, (Consumer Safety Unit, Department of Trade, London) Snyder, R.G. Spencer M.L. Owings C.L. and Schneider L.W. 1975, Anthropometry of US  Infants and Children (SP394), (Society of Automotive Engineers(SAE), Washington, DC) Synder, R.G., Schneider L.W., Owings C.L., Golomb D.H. and Schork M.A. 1977, Anthropometry of infants, children and youths to age 18 for product safety design, Report# UM-HSRI-77, (Consumer Product Safety Commission, Washington, DC) (Quoted in Norris and Wilson 1995) Porter, M.L. 2000, The Anthropometry of the fingers of Children, In the proceedings of the IEA2000/HFES Congress, San Diego, (Human Factors and Ergonomics Society, Santa Monica) Steenbekkers, L.P.A., 1993, Child development design implication & accident prevention, No 1 in Physical Ergonomics Series, (Delft University of Technology (TU Delft), The Netherlands)  

BS 5665: Safety of Toys Part 1,Specification for Mechanical and Physical Properties, (British Standards, London) BS,

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Getting stuck- the anthropometry of young children's fingers

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