(PERSONAL IDENTIFICATION TECHNIQUES)

FINAL COVERAGE
Compiled By: Oswaldo P. Lapena, MS.Crim.

MODULE 1 (Final Coverage)

TOPIC:
THE CLASSIFICATION FORMULA AND EXTENSION

Division classification of Fingerprints

1. Primary Classification
2. Secondary Classification
a. Capital Letter Group
b. Small Letter Group

3. Sub-Secondary Classification
4. Major Classification
5. Final Classification
6. Key Classification

KC MC PC SC SSC FC

CLASSIFICATION – refers to the sorting of things into division or group so that

they can at later time be quickly located.

Fingerprint Classification Formula

The original henry system, as it was adopted by Scotland Yard in 1901,
converted ridge patterns on all 10 fingers into a series of letters and numbers
arrange in the form of a fraction.

KC MC PC SC SSC FC
MC PC SC SSC FC

CLASSIFICATION LINES- It refers to a long line, which is usually placed on the right
corner of the fingerprint card where the classification formula is exhibited.
Finger blocking

At this point it is necessary to mention that when prints are

classified, markings are indicated at the bottom of each finger block to
reflect the type. The following symbols are used:

a) Under the Index Finger, the appropriate capital letters should

be placed for every pattern except the Ulnar Loop;

b) Under all other fingers, the appropriate letter should be placed

for every pattern except the ulnar loop and the whorl, as
follows:

Arch . . . . . . . . . . . a
Tented Arch . . . . . t
Radial Loop . . . . . . r

c) Ulnar loops in any finger are designated by a diagonal line

slanting in the direction of the loop.

d) Whorls in any finger are designated by the letter capital “W”.

 R R U W R

r R W r

T C C D U

t W W W

U U C T D

W t W

W X A U R
 WW W a a r

A. PRIMARY CLASSIFICATION
 -is the summation of all numerical value assigned to Whorls (Plain Whorl, double
loop whorl, central pocket loop whorl and accidental loop whorl) appearing in the
fingerprint chart which are expressed as numerators and denominators plus the
pre established fraction of 1/1

-PATTERNS AS TO NUMBER VALUE ARE:

1. Patterns with numerical value are:

ALL WHORLS- Plain whorl, central pocket loop whorl, double loop whorl
and accidental loop whorl.

2. Patterns without numerical value area:

ARCHES- Plain arch and tended arch

LOOPS- Ulnar loop and Radial Loop

-FOUR STAGES TO A PRIMARY CLASSIFICATION-

1. PAIRING-
-The ten fingerprints from the corresponding finger are divided into five (5) pairs
are as follows:

a. The first pair is composed of the right thumb and the right index finger.
(Nos. 1 & 2).
b. The second pair is composed of the right middle finger and right ring
Finger. (Nos. 3 & 4)
c. The Third pair is composed of the right little finger and the left thumb
finger. (Nos. 5 & 6)
d. The fourth pair is composed of the left index finger and left middle finger. (7
& 8 ).
e. The fifth pair is composed of the left ring finger and the left little finger.
(Nos. 9 & 10).

1. 2. 3. 4 5.

6. 7 8 9 10.

2. ASSIGNING NUMERICAL VALUE TO WHORLS

-This numerical value to the corresponding fingers is permanent as follows:

a. Whorl appearing in the first pair has a numerical value of 16 each.

 b. Whorl appearing in the second pair has a numerical value of 8 each.
c. Whorl appearing in the third pair has a numerical value of 4 each.
d. Whorl appearing in the fourth has a numerical value of two each.
e. Whorl appearing in the fifth pair has a numerical value of one.

16 16 8 8 4

4 2 2 1 1

***NOTE. Always add one to the numerator and denominator.

3. KNOWING THE NUMERATORS AND DENOMINATORS IN THE PAIRS.

-The first pattern of every pair is the denominator while the second pattern of the pair is
the numerator, there will be five numerators coincide to denominators of the set of 10
fingerprints.

2, 4, 6, 8 10 = numerators
FINGERS: 1, 3, 5, 7, 9 = denominators

16 16 8 8 4

1 2 3 4 5
4 2 2 1 1

6 7 8 9 10

4. SUMMING THE NUMERICAL VALUE OF WHORL ASSIGNED TO THE FINGERS PLUS

PRE-STABLISHED FRACTION 1/1.
- Get the total value of all the numerators and denominators add the fraction of 1/1.

Example:

W W W W W

W W W W W
W W W W W

W W W W W
N- 16 D- 16
8 8 PC
4 4 32
2 2
1 1 32
-------- ---------
31 + 1 =32 31 + 1 = 32

R W U W A

r W W a
D T W C X

W T W W W

N- 16 D-
8 PC
4
2 32
1 1
-------- --------- 2
31 + 1 =32 1+1=2

A T R U W

a T r W
C D X X X

W W W W W

N- D–

PC
4 4
2 2
8
1 1
----------------- -----------------
8
7 +1 = 8 7+1=8
 C U R A D

W r a W

D A C A U

W A W aa

N- D– 16 PC
7
4 4
2 21

____________ __________
6 +1 = 7 20 + 1 = 21

U T T U T

T t t

C A U U U

W A

N- D- PC
5

4 1

____________ _____________
4 +1 = 5 +1=1

B. SECONDARY CLASSIFICATION (Capital and small letter group)

CAPITAL LETTER GROUP

The Secondary classification appears just to the right of the fractional numerals,
which represents the Primary. It is shown in the formula by capital letters
representing the basic types of patterns appearing in the index fingers of each
hand. The right hand being the numerator and the left hand the denominator.

There are five (5) basic types of patterns, which can appear:

1. Plain Arch - - - - - - - - A
2. Tented Arch - - - - - - T
3. Radial Loop - - - - - - R
4. Ulnar Loop - - - - - - U
5. Whorl - - - - - - - - - - W, (C, D, X)

A T R U W

C D X A T

SC
T
W

SECONDARY CLASSIFICATION (Small Letter group)

- Prints with an arch or tented arch in any finger or a radial loop in

any except the index finger constitute the small letter group of the
secondary classification. Such “small-letters”, with the exception of
those appearing in the index fingers, and any pattern that are not
included in “art” are represented by dash (-) are brought up into the
classification formula in their proper relative positions immediately
adjacent to the index fingers. The fingerprint appearing in the right fingers is
the numerator while the fingerprint appearing in the left fingers is the denominator.

They are given by following pattern type.

 Arches= a,
 Tented aches =t,
 Radial loops =r,
 Ulnar loop (U) and Whorls (W) are indicated by a hyphen (-)

A T R U W

C D X A T
 SC
aTr--
-W-at

R W C D T

r W W W t
U A X R T

A W r t

N- 16 D-
PC SC
8 8
27 rW--t
2
9 -A-rt
___________ __________
26 +1 = 27 8 +1 = 9

SECONDARY CLASSIFICATION BY SMALL LETTER GROUP

- This refers to the three types of fingerprint pattern namely: radial loop; plain
arch; and tented arch. Whenever any of this pattern appear in any fingerprint,
excluding the two index finger, each symbol in small letter be exhibited in the
classification line as : r - for radial loop , a - for plain arch, and t – tented
arch. Fingerprint patterns that are not under “rat” will be represented by a dash
in the classification line. Write them after the secondary classification by capital
letters depending on the finger of origin. The four fingers involved in the right
hand are the numerators and the four fingers at the left hand are denominators.

R R R R T

r R r r r
R R R R R

r R r r r
 or

A R D D C
1 2 3 4 5
U U W T X
6 7 8 9 10

N- D-
8 8
4
2
1
___________ __________
11 + 1 = 12 12 + 1 = 13

W U A D R

C X D U A

PC SC
N- D - 16
-Ua-r
8
15
4
-W--a
2 2
19
_________ __________
14 + 1 =15 18 + 1 = 19

A T C D U

a T W W
R A T W X

r A t W W
 PC SC

10 aT---
rAt--
10

C. SUB-SECONDARY CLASSIFICATION

- This is done by ridge counting of (radial or ulnar) and ridge tracing the whorls
( w,c,d,x) appearing in index, middle and ring finger of both right and left hand.
Whenever loops are found in the above mentioned fingers, each should be ridge
counted, the result of such count in number be displayed in the right upper corner
of the frame where found and later on deducted into symbols of the classification
line, Whorls are ridge traced but unlike the loops, the result of such tracing is
automatically brought into symbols in the upper corner of the frame where found
and later on the same symbol is exhibited into the classification, the right index,
middle and ring fingers are the numerators while the opposite finger from the left
hand are the denominators. Arches are merely represented by a dash (-) in
the classification line.

RIDGE COUNTING AND RIDGE TRACING

Ridge Counting Procedure

The two important factors in the classification of loops and whorls are done by
ridge counting and tracing. By ridge count it means the enumeration of the number of
ridge characters touching or passing between the core and delta, excluding core and
delta. In loops, it is suggested to begin the count from delta to the core.

RIDGE COUNTING
- Is the total number of ridge intervening between the delta and the core. Delta and
Core are not included in the count, the first ridge after the delta is counted as one
and all other succeeding ridges thereafter the core is reach and counted.

RULES IN RIDGE COUNT OF LOOPS

1. Ridge count is always starts from the delta to the core.
2. Ridges are counted only when they actually crossed or touched the straight
line ( red line on the dish of the lens) between the delta and the core.
a. A bifurcation is 2 ridges.
b. Ending ridge is counted as 1 ridge.
c. A dot ridge is counted as one ridge.
d. Criss crossing of the two ridges as 2 ridges.
e. meeting of the two ridges as 2 ridges
 f. island ridges as 2 ridges
g. long or short ridge as 1 ridge each.

TABLE FOR SYMBOL OF LOOP AS A RESULT OF RIDGE COUNT

1. A ridge count of 1 to 9, inclusive in the two index finger is deducted into

symbol capital letter “I” (inner) while 10 or more is “O” (outer). Symbol be
exhibited in the classification line only.
2. A ridge count of one to ten ( 1 to 10) inclusive of the two middle finger is
deducted into symbol capital letter “I” (inner) while 11 or more is “O”
(outer).
3. A ridge count of 1 to 13 inclusive of the two ring fingers is deducted into
symbol capital letter “I” while 14 or more is capital letter “O”.

R (9) U (10) R (13)

U (10) R (11) U (14)

SSC
III
OOO

R (8) U (2) R (15)

U (11) R (9) U (20)

SSC

IIO
OIO

R (11) U (6) R (18)

U (12) R (12) U (1)

SSC
OIO
OOI
RIDGE TRACING (FOR WHORLS ONLY)

-It is the tracking or trailing the ridge commencing from the left delta
going across to the right delta or nearest in distance, the symbols to be write are
as follows: “I” for inner, “M” for meeting, “O” for outer.

RULES IN RIDGE TRACING

1. Ridge tracing always from the left delta going to right delta or nearest
to that point.
2. When the ridge being traced ends abruptly, the next ridge below is its
continuity to effect the tracing.
3. When the left delta is at the end of a ridge or on a dot ridge, the
ridge below is tracked down to culminate the tracing.
4. When the ridge is traced forks into two branches the lower branch is
trailed until the tracing is consummated.

TABLE FOR SYMBOLS OF WHORLS AS A RESULT OF RIDGE TRACING

1. When the ridge being traced (from the left delta) goes inside
or in-front of the right delta and there are three (3) or more
intervening ridges, the tracing is known as inner and
represent by symbol capital letter I.
2. When the ridge traced goes either inside or outside of the
right delta and there are two (2) or less ridges intervening,
the tracing is known as MEETING and represented by symbol
capital letter M. The symbol be exhibited in right upper
corner of the frame found and also in the classification line.
3. When the ridge being traced goes OUTSIDE or below the
right delta and there are 3 or more ridges intervening, the
tracing is known as OUTER and represent by symbol capital
letter O.

Examples:

W 3 (I) W 3 (O) W 2 (I)

W 5 (O) W 7 (I) W 1 (I)

SSC
 IOM
OIM

D 2 (O) C 2 (O) W 2 ()

W W W
C 6 (O) D 1 () C 5 (I)

W W W

SC SSC
MMM

OOI

U 20 A R1

X 6 (O) D 10 (O) T

SSC
O-I
OO-

U 20 A Amputation

X 6 (O) D 11 (O) T

SSC
O--
OO-
FINAL CLASSIFICATION

- It is by ridge count of the loops and whorls from the two little fingers. The result
of the ridge count is number be exhibited in the right upper corner of the frame
where found and also re-exhibited at the extreme right of the classification line. The
ridge count of the right little finger is the numerator while that of the little left finger
is the denominator. Arches are represented by dash (-) in the classification line.

Procedures:

- A plain whorl or a central pocket loop whorl is treated as an ulnar loop in the ridge
count.
- Double loop be ridge counted to an upright loop.
- An accidental loop whorl is ridge counted from the extreme corresponding delta to
the nearest core.

W (13)
C (11)

FC
13
11

- If all fingers are imputed or missing at birth, the classification will be:

M 32 W MMM
M 32 W MMM

13

11
25

11
10
 6
.

KEY CLASSIFICATION- The key classification represent the ridge count of the first
loop appearing in a set of prints, beginning with the thumb
of the right hand, but excluding the little fingers. The Key,
no matter where it is found is always written at the
extreme left of the numerator. In a set of prints in which
no loops appear, but which have whorls in all fingers and
thumb, the key is obtained by making a ridge count of the
first whorl except finger involve for final classification.
Arches are represented by a dash in the classification line..

R (15)

KC
15

KC MC PC SC SSC FC
- - 1 aAaaa/ --- -
aAaaa
- 1 aAaaa/aA3a --- -

MAJOR CLASSIFICATION
- It is similar to the previous (sub-secondary classification) it applies only to the
thumbs. This is by the ridge counting the loop and ridge tracing the whorls
appearing from the thumbs. That a loop found therein is ridge counting, the result is
exhibited in the right upper corner of the frame where the loop is found and later on
 expressed in symbol in the classification line. A whorl however, is ridge traced, as
done in the sub - secondary classification, with the same table for symbol used. Two
sets of table for symbols are used in the loops whenever loop from the left thumb is
17 or more. Arches are represented by a dash in the classification line. The right
thumb is the numerator and the left thumb is the denominator.

TABLE “ A” FOR LOOP SYMBOL (RULE I )

1. 1 to 11 inclusive = S (small)
2. 12 to 16 inclusive = M (medium)
3. 17 or more = L (large)

TABLE “B” FOR LOOP SYMBOLS (RULE II)

1. 1 to 17 inclusive = S (small)
2. 18 to 22 inclusive = M (medium)
3. 23 or more = L (large)

NOTE:
-IF THE VALUE OF THE LEFT THUMB IS 17 or more USE Table B/RULE II.

-Whorls are ridge traced and the symbols used in the sub secondary classification
should also be made applied in this major classification.

R (15)
U (20)

MC
S
M

W 1 (O)
R (18)

MC
M
L

W 5 (o)
W 2(i)
 MC
O
M

Classification of Amputations and Fingers Missing at Birth

When one or more amputations appear on a fingerprint card, it may be filed separately from
those having no amputations in order to facilitate searching. It is to be noted that
before it may be filed in the amputation group, the card must contain a definite and
unequivocal statement or marking by the contributor to the effect that a certain
finger/s have amputated or were missing at birth. These prevents the appearance on
later cards of impressions of fingers thought to have been amputated but which in
reality were merely injured and bandaged when previous prints were submitted.
1. If one finger is amputated, it is given a classification identical with that of the
opposite finger, including pattern, ridge count or tracing, and referenced to every
other possible classification.
2. If two fingers are amputated, they are given classifications identical with the fingers
opposite, with no additional tracing.
3. If two amputated fingers are opposite to each other, both are given the classification
of whorls with meeting tracings.
4. When a fingerprint card bearing a notation of fingers missing at birth is classified,
the missing fingers should be treated as amputated in that they are given the
identical classification of the opposite fingers and are filled in the amputation group.
As these fingers are missing from a prenatal cause, they would have always received
the identical classification of the opposite finger on any previous occasion.
5. If all 10 fingers are amputated or missing at birth, the classification will be M 32 W
MMM
M  32  W MMM
6. If both hands are amputated or missing at birth, the footprints should be taken
as they, too, bear friction ridges with definite patterns. A foot prints file is
maintained by the FBI for identification purposes in instances where the subject has
all fingers amputated or missing at birth.
7. Partially amputated fingers often present very complex problems and careful
consideration should be given to them. As no definite rule maybe applied, it is a
matter of experience and judgment as to their preferred classification. In those
instances in which a partially amputated finger has half or more than half of the
patterns are missing, it is given the classification of the opposite finger. It will be
filed in the amputation group under the classification of the opposite finger and
reference searches should be conducted in all possible classification in the non-
amputation group.
8. Generally, a “ tip amputation”, or one which has less than half of the first joint
amputated, will always be printed in the future. Therefore, a partially amputated
finger with less than half of the pattern are missing is classified as it appears. It will
be filed in the non-amputation group.

Applications:
1.
U 19 R (9) U (10) R (13) W 13

Amputated U (10) R (11) U (14) D 17

(U (19))

2. 
U 19 R (9) U (10) R (13) W 13

Amputated Amputated R (11) U (14) D 17

(U (19)) (R (9))

3. 
Amputated R (9) U (10) R (13) W 13
(W (m))

Amputated U (10) R (11) U (14) D 17

(W (m))

Same explanation on rule number 1

4. M 32 W MMM
M 32  W
MMM

CLASSIFICATION OF BANDAGE OR UNPRINTED FINGERS

Problems in the taking ink fingerprints, an indication to the effect injured, bandage, are
not sufficient to file a fingerprint card. It is obvious that a fingerprint card bearing these
notations cannot be properly classified or filed. If the injury is temporary, and if possible, these
prints should not be taken until after healing.
If fingers are injured to the extent that it is possible to secure inked impressions by
special inking devices, the unprinted fingers are given classification identical with the
classifications of the fingers’ opposite.

Scarred patterns

Standard procedures to be followed

Fingerprint classifiers are frequently faced with problems involving scarred impressions
as well as amputated and missing fingers. Scarred patterns sometimes cause
complications in determining the pattern itself, ridge counting, and ridge tracing. To
complete a classification formula, there are standard procedures that should be
followed: (Vinluan et,al.)

1. When a fingerprint is so marked by a scar that the general pattern type is

unrecognizable and the ridge-counting and ridge tracing cannot be determined, the
impression should be given the same pattern interpretation and sub-classification
with the corresponding finger of the other hand.
2. When a fingerprint is partially scarred and the general pattern type can be
determined with reasonable accuracy but the ridges cannot be counted or traced,
the impression should be given the ridge count or tracing value of the corresponding
finger of the other hand, if the corresponding fingers are of the same general
pattern type. If the corresponding finger is not of the same type, the scarred
impression should be given a probable value and referenced to all other possible
combinations.
3. When a fingerprint is scarred beyond its general pattern type recognition and the
ridge counting and tracing cannot be determined with reasonable accuracy, and it so
happens that the corresponding finger of the other hand is also scarred, both
patterns are arbitrary interpreted as meeting whorls.
4. Those rare patterns in which dissociated ridges appear are interpreted in the same
manner as are scarred patterns.