ISO 2549:1972

Overview

ISO 2549:1972 is an international standard established by the International Organization for Standardization (ISO) that defines a precise method for determining the tuft leg length of hand-knotted textile floor coverings. This standard is specifically applicable to all hand-knotted carpets where the pile-or tuft legs-can be shorn from the woven ground and applies to knots tied either by finger or hook. It excludes carpets with varying tuft leg lengths unless those areas are measured separately.

The standard aims to ensure consistent, accurate measurement of tuft leg length, a critical parameter that influences carpet thickness, appearance, durability, and performance. Adopted globally, this standard supports manufacturers, testing laboratories, and quality control professionals in maintaining uniformity and reliability in carpet production and testing.

Key Topics

• Scope and Application
  ISO 2549:1972 applies to all hand-knotted carpets with uniform tuft leg length that can be measured above the woven ground. For carpets with different tuft lengths, separate measurements must be taken for each area.

• Definition of Tuft Leg Length
  The tuft leg length is the distance measured from the point where a tuft leg emerges from the woven ground to its free end, excluding the woven base.

• Measurement Principle
  Tuft leg length is determined by inserting flat metal gauges of known thickness into the carpet pile at right angles to the woven ground, selecting the gauge height that corresponds precisely to the tuft leg length.

• Measurement Procedure

  1. Insert metal gauges between two rows of tuft legs ensuring firm contact with the woven ground.
  2. Support the tuft legs vertically using the gauge.
  3. Identify the gauge that fits best and verify by checking adjacent higher and lower gauge sizes.
  4. For carpets with varying tuft heights, measure each level separately.
  5. Perform at least ten measurements across different carpet locations per pile height.

• Apparatus
  The standard specifies using flat metal gauges in 1 mm height increments to accurately gauge tuft leg lengths.

• Reporting Requirements
  Test reports must include details of the measurement method, values for each measurement, and the mean tuft leg length per pile level.

Applications

ISO 2549:1972 is essential for:

• Carpet Manufacturers
  Ensuring consistent pile height quality to meet design specifications and customer expectations.

• Quality Control and Testing Laboratories
  Performing standardized tests for carpet tuft lengths to verify compliance with product standards and contract requirements.

• Product Development
  Comparing different hand-knotted carpets in terms of pile thickness and appearance for product improvement.

• Importers, Exporters, and Regulatory Bodies
  Verifying that hand-knotted carpets conform to international standards, facilitating trade and quality assurance.

By applying this standard, stakeholders can enhance product uniformity, improve manufacturing precision, and provide reliable data for technical evaluation.

Related Standards

• ISO 8543 - Textile floor coverings - Vocabulary
  Provides definitions for textile floor covering terms including carpet construction attributes related to tuft legs.

• ISO 1833 - Textiles - Quantitative chemical analysis
  Relevant for analyzing fiber composition in carpets, complementing physical dimension measurements.

• ISO 7211 series - Textile floor coverings - Methods for determination of dimensions
  Covers additional measurement procedures for carpets including thickness and profile that can complement tuft leg length assessment.

Keywords: ISO 2549:1972, tuft leg length, hand-knotted carpets, textile floor coverings, carpet pile measurement, woven ground, carpet thickness, carpet quality standards, textile standards, carpet testing, pile height measurement.