Sub Secondary Classification is a subdivision in the Henry fingerprint system whose values are represented by symbols based on the ridge tracing and counting values of whorls and loops pattern. Index, middle, and ring finger values are used to classify this division.
In this short post, you’re going to get to know what are the rules of using this division along with how to calculate it even in the case of amputated and scarred fingers.
Rules of Using Sub Secondary Division
- Fingers Used: Index, Middle, and Ring finger
- Numerator: Right Index, Middle, Ring (finger number 2, 3, 4)
- Denominator: Left Index, Middle, and Ring (finger number 7, 8, 9)
- Position in classifying line: immediately after secondary classification
- Patterns: Loops and Whorls
- Values: Ridge tracing and Ridge counting
- Ridge counting for loops
- Ridge Tracing for whorls
Sub Secondary Classification is Not Used in:
1. Arches: Plain and tented arches on the index, middle, and ring finger.
2. Small Letter Grouping: Henry’s classification number uses small letter groups with secondary classification values.
Values for Sub Secondary Classification
While filling the card, the value of ridge count and traces are indicated in the corresponding letter.
A. Letter Designation for Ridge Counting for Loops
| Fingers | Loops Count Symbol |
|---|---|
| Index finger | • Inner (I) = 1 to 9 • Outer (O) = 10 or more |
| Middle finger | • Inner (I) = 1 to 10 • Outer (O) = 11 or more |
| Ring finger | • Inner (I) = 1 to 13 • Outer (O) = 14 or more |
B. Letter Designation for Ridge Tracing of Whorls
The ridge tracing is always considered with respect to the right delta. Following are the values for index, middle and ring finger:
- Meet (M) = 0, 1, or 2 ridges inside or outside the right delta
- Inner (I) = 3 or more inside the right delta
- Outer (O) = 3 or more outside the right delta
How to Calculate Sub Secondary Classification Number?
Let’s take an example and understand how you can come up with the sub-secondary division number.
Step 1: Identifying Patterns
The following is the visual representation of the various patterns along with their respective ridge counting and tracing values (/ and \ dashes are used for the ulnar loops, w.r.t hands). You can check the dedicated post on how you can fill 10-digit cards (with rules).
- Index finger:
- RI = Whorl
- LI = Radial loop
- Middle finger
- RM = Ulnar loop
- LM = Whorl
- Ring finger:
- RR = Ulnar loop
- LR = Whorl
Step 2: Calculating Ridge Tracing and Counting
- Index finger
- RI = 2, outside the right delta
- LI = 15
- Middle finger
- RM = 14
- LM = 2, inside the right delta
- Ring finger
- RR = 16
- LR = 3, inside the right delta
Step 3: Respective SubSecondary Classification Symbol
- Index finger
- RI Value = 2= M (whorl, M= 0,1,2)
- LI Value = 15= O (loop, O= 9+)
- Middle finger
- RM Value = 14 = O (loop, O=10+)
- LM Value = 2 = M (whorl, M= 0,1,2)
- Ring finger
- RR Value = 16 = O (loop, O=13+)
- LR Value = 3= I (whorl, I= 3 or more inside the right delta)
Step 4: Representing in Henry Fingerprint System
- Numerator: MOO
- Denominator: OMI
The following is the Henry number for this 10-digit card.
Sub Secondary Classification in Amputated & Scarred Documents
A. Scarred Fingerprints
The following table sets the rule for sub secondary division in the case of scarred fingerprints.
| Possible Rule | Values |
|---|---|
| Rule 1: Fully Disfigured Impressions | Patterns from corresponding opposite finger |
| Rule 2: Partially scarred with possible known pattern but inconclusive ridge count/trace | • If the same general pattern on opposite finger: Ridge count/trace value of opposite finger. • If different general patterns: probable count/trace value assigned. |
| Rule 3: Partially scarred with inconclusive pattern (whorl/loop) but possible ridge count/trace | Ridge counting/tracing of partially scarred fingerprints with the opposite thumb pattern type |
| Rule 4: Both Corresponding Opposite Finger are fully disfigured | Whorls pattern with meet trace value |
| Rule 5: Bandaged prints | Prints are taken after healing |
B. Amputated Fingers
Following table states the possibility of finding sub secondary values in amputated fingers.
| Possible Rule | Values |
|---|---|
| Rule 1: 1, 2, 3, or 4 Amputated Fingers | Patterns from corresponding opposite fingers |
| Rule 2: Two Opposite Finger are Amputated | Whorls with meet trace value |
| Rule 3: All fingers are Amputated | MMM / MMM |
| Rule 4: Both Hands are Amputated | Footprints are used |
Practical Worksheet for Sub Secondary Classification
Three practice worksheets are included. For simplicity, I drove out 10-digit card values in form of a table. You can do this too. Check my other post on how to extract data from a 10-digit card and present it in form of a table.
Practice Set #1
Step 1: Identifying Patterns
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Ulnar loop | Radial loop | Ulnar loop |
| Left Hand | Radial loop | Whorl | Ulnar loop |
Step 2: Calculating Ridge Tracing and Counting
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Ulnar= 10 counts | Radial= 16 counts | Ulnar= 9 counts |
| Left Hand | Radial= 8 counts | Whorl= 4, outside | Ulnar= 10 counts |
Step 3: Respective SubSecondary Value
- Index finger
- RI Value = 10= O (loop, O= 10 or more)
- LI Value = 8= I (loop, I= 1 to 10)
- Middle finger
- RM Value = 16= O (loop, O=11 or more)
- LM Value = 4= O (whorl, O= 3 or more for right delta)
- Ring finger
- RR Value = 9= I (loop, I=1 to 13)
- LR Value = 10= I (loop, I= 1 to 13)
Step 4: Representing in Henry Fingerprint System
- Numerator: OOI
- Denominator: IOI
Practice Set #2
Step 1: Identifying Patterns
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Ulnar loop | Radial loop | Ulnar loop |
| Left Hand | Whorl | Whorl | Ulnar loop |
Step 2: Calculating Ridge Tracing and Counting
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Ulnar= 11 | Radial= 10 | Ulnar= 13 |
| Left Hand | Whorl= 3, inside | Whorl= 3, outside | Ulnar= 16 |
Step 3: Respective SubSecondary Value
- Index finger
- RI Value = 11= O (loop, O= 9+)
- LI Value = 3= I (whorl, I= 3 or more inside of right delta)
- Middle finger
- RM Value = 10= I (loop, I= 1 to 10)
- LM Value = 4= O (whorl, O= 3 or more outside of right delta)
- Ring finger
- RR Value = 13= I (loop, I=1 to 13)
- LR Value = 16= O (loop, O= 13+)
Step 4: Representing in Henry Fingerprint System
- Numerator: OII
- Denominator: IOO
Practice Set # 3: Amputated Finger
Step 1: Identifying Patterns
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Whorl | Whorl | Ulnar loop |
| Left Hand | Amputated | Ulnar loop | Ulnar loop |
Step 2: Calculating Ridge Tracing and Counting
| Index Finger | Middle Finger | Ring Finger | |
|---|---|---|---|
| Right Hand | Whorl= 4, outside | Whorl= 3, inside | Ulnar= 9 counts |
| Left Hand | *Whorl= 4, outside | Ulnar= 11 counts | Ulnar= 14 counts |
Step 3: Respective SubSecondary Value
- Index finger
- RI Value = 4= O (whorl, O= 3 or more outside of right delta)
- LI Value = 4= O (whorl, O= 3 or more outside of right delta)
- Middle finger
- RM Value = 3= I (whorl, I= 3 or more inside of right delts)
- LM Value = 11= O (loop, O= 11 or more)
- Ring finger
- RR Value = 9= I (loop, I=1 to 13)
- LR Value = 14= O (loop, O= 14 or more)
Step 4: Representing in Henry Fingerprint System
- Numerator: OII
- Denominator: OOO
Frequently Asked Question
1. What are the fingers included in the sub secondary classification?
Right Index (finger #2), right middle (finger #3), right ring (finger #4), left index (finger #7), left middle (finger #8) and left ring (finger#9) are included in sub seconday classification of fingerprnts.
2. How to obtain sub secondary classification?
Values of sub secondary division are computed based on the ridge trace or counts of whorls and loops in the index, middle and ring finger of both hands. Based on the trace and counts values respective symbols are allocated to obtain sub secondary values.
3. What is the difference between secondary and sub secondary classification?
Sub secondary and secondary classification are subdivisions of Henry classification. Moreover, the values of secondary classification are given by the patterns on the index fingers. While, for sub secondary, the values are in form of symbols of ridge trace and counts and include an index, middle, and ring fingers.
4. If the loop pattern is located in the middle finger and it has 10 ridge counts, how shall we write this in the sub secondary division?
If the middle finger has a ridge count value of 10, it is represented by the symbol ‘I’ (inner). However, if the middle finger value is more than 10, it is represented by the symbol ‘O’ (outer)
Also Read:
- Final Classification of Fingerprint: Rules, Worksheet, and Amputated Fingers
- Key Classification of Fingerprint: Rules, Procedure, & Example
- Second Sub Secondary Classification of Fingerprint: Rules, Procedure & Example
- Extensions of Henry Fingerprint System: WCDX & Special Loops
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