Link points to Internet Archive / others. Not hosted by InfraLens. Details
IS 3364:2000 (Part 2) is the Indian Standard (BIS) for methods of measurement and evaluation of defects in timber, part 2: converted timber. This standard specifies the methods for measuring and evaluating various natural and manufacturing defects in converted (sawn) timber. It provides standardized procedures to quantify defects like knots, shakes, splits, wane, and warp, which is essential for timber grading and quality control.
Methods of measurement and evaluation of defects in timber, Part 2: Converted timber
! Moisture content heavily influences warp; always record the moisture content at the time of evaluating bow, cup, spring, and twist.
! When measuring knots, it is crucial to distinguish between live (sound) knots and dead (loose/decayed) knots, as their structural implications differ.
! Wane should be measured at the point of maximum reduction of the cross-section.
EN 1310:2018CEN (European Committee for Standardization), Europe
HighCurrent
Round and sawn timber — Method of measurement of features
Specifies methods for measuring features of round and sawn timber, covering dimensions and common defects.
ISO 4480:2018ISO (International Organization for Standardization), International
HighCurrent
Round timber — Measurement of features
Provides methods for measuring the features of round timber, focusing on dimensions and form deviations.
BS 5630:1978BSI (British Standards Institution), United Kingdom
MediumWithdrawn
Code of practice for the measurement of defects in timber (including stress grading)
Provided methods for measuring timber defects, but is outdated and has been replaced by harmonized European standards.
ASTM D9 - 09a(2021)ASTM International, USA
LowCurrent
Standard Terminology Relating to Wood and Wood-Based Products
Provides standard definitions for wood defects and features, but does not specify measurement methods.
Key Differences
≠IS 3364 measures knot size as the average of its maximum and minimum diameters, whereas EN 1310 defines it as the smallest diameter of the knot's cross-section.
≠Sweep (bow) in IS 3364 is expressed as a dimensionless ratio of maximum deviation to log length (d/L), while EN 1310 expresses it in centimetres per metre of length (cm/m).
≠For measuring end splits/checks, IS 3364 measures the maximum width and depth. In contrast, EN 1310 measures the diameter of the smallest circle that can enclose the check pattern on the end face.
≠IS 3364 defines a knot cluster qualitatively as knots where intermediate wood fibres are deflected. EN 1310 provides a more quantitative rule, often based on the distance between knots relative to their size.
≠The Indian standard is a standalone document for defect measurement. The European system is more modular, separating measurement methods (EN 1310) from quality classification rules (e.g., EN 1927 series).
Key Similarities
≈All standards address the same fundamental set of log defects, including knots, splits, decay, insect damage, grain deviation, and form deviations like sweep and taper.
≈The common practice of measuring log diameter by averaging two perpendicular measurements to account for out-of-roundness is specified in IS 3364, ISO 4480, and EN 1310.
≈Measurements for volume and defect quantification are consistently taken 'under bark' or 'excluding bark' to ensure accuracy and comparability.
≈The measurement of log length in both IS 3364 and ISO 4480 is defined as the shortest distance between the two end cross-sections.
Parameter Comparison
Parameter
IS Value
International
Source
Knot Size Measurement
Average of the maximum and minimum diameters of the knot.
The smallest diameter of the knot cross-section.
EN 1310:2018
Expression of Sweep
Ratio of max deviation to log length (d/L).
Max deviation in centimetres per metre of length (cm/m).
EN 1310:2018
Taper Calculation
Difference between butt-end and top-end diameters, in cm per metre of length.
Difference in diameter over a given length, expressed in cm/m.
ISO 4480:2018
End Check Measurement
Maximum width and depth of the check on the end surface.
Diameter of the smallest circle enclosing the check pattern on the end face.
EN 1310:2018
Log Diameter Measurement Principle
Average of two measurements taken at right angles to one another.
Average of two perpendicular measurements (or the smallest diameter).
ISO 4480:2018
Rounding of Length Measurement
Rounded down to the nearest 5 cm.
No specific rounding rule prescribed in the method; subject to national rules.
ISO 4480:2018
⚠ Verify details from original standards before use
Key Values5
Quick Reference Values
Measurement of knotMaximum distance between lines enclosing the knot parallel to the longitudinal edges
Measurement of bowMaximum deviation from a straight edge connecting the two ends of the face
Measurement of cupMaximum deviation from a straight edge placed transversely across the width of the face
Measurement of springMaximum deviation from a straight edge connecting the two ends of the edge
Measurement of slope of grainMeasured over a distance of not less than 250 mm
Tables & Referenced Sections
Key Tables
No tables data
Key Clauses
Clause 4 - Measurement of Knots
Clause 5 - Measurement of Shakes, Splits and Cracks
Clause 6 - Measurement of Wane
Clause 7 - Measurement of Warp (Bow, Cup, Spring, Twist)