ISO 8904:1990

Overview

ISO 8904:1990 establishes international methods for measuring the size of broadleaved sawn timber, specifically focusing on the length, width, thickness, and volume of sawn timber pieces. Developed by the International Organization for Standardization (ISO), this standard applies to unplaned, square-edged, and unedged sawn timber made from broadleaved species. The purpose is to provide clear, uniform, and reliable measurement techniques for manufacturers, suppliers, and buyers in the timber industry, supporting consistency and quality across global markets.

Key Topics

• Measurement of Length: Specifies the process for determining the minimum distance between the two ends of a sawn timber piece, with both ends cut perpendicular to the timber’s longitudinal axis.

• Measurement of Width:

  • Square-edged timber with parallel edges: Measured at any place along the length where there is no wane, at least 150 mm from the end.
  • Square-edged with tapered edges: Measured at mid-length at a location free of wane.
  • Unedged timber: Measured on both faces at the midpoint; the average of both measurements is used, disregarding bark.
  • Unedged timber under 40 mm thick: Measured along the narrower face at the midpoint.
  • All width measurements are rounded to the nearest 10 mm.

• Measurement of Thickness: Can be taken at any place along the length, no closer than 150 mm to an end.

• Volume Calculation:

  • Individual pieces: Volume is the product of nominal thickness, width, and length, expressed in matching units.
  • Lots of sawn timber: Volume calculated and rounded to the nearest 0.001 m³.

• Use of Standardized Terms: Relies on definitions outlined in ISO 1032 for terminology related to sawn timber.

Applications

The measurement methods specified in ISO 8904:1990 are essential for:

• Timber Producers and Processors: Ensuring that broadleaved sawn timber is measured consistently to meet buyer and regulatory requirements.
• Quality Control and Inspection: Facilitating reliable assessment and comparison of timber products across different suppliers and markets.
• Trade and Procurement: Providing standard guidelines for timber sizing, which support fair trade, accurate pricing, and contract fulfilment.
• Regulatory Compliance: Assisting organizations in aligning with international best practices and legal frameworks for timber products.

By using ISO 8904:1990, stakeholders can minimize disputes regarding measurements, enhance product quality, and improve supply chain efficiency in the timber industry.

Related Standards

• ISO 1032:1974 - Coniferous sawn timber - Sizes - Terms and definitions: Provides key terminology and definitions relevant to the measurement of sawn timber, referenced in ISO 8904:1990.
• ISO/TC 55: The technical committee responsible for the development of standards related to sawn timber and sawlogs, including ISO 8904.

For best practice, users are encouraged to reference the latest versions of these related standards to ensure full compliance and awareness of current measurement guidelines.

Keywords: ISO 8904:1990, broadleaved sawn timber, timber measurement methods, sawn timber size, timber thickness, timber width, timber volume calculation, timber industry standards, international timber measurement, square-edged sawn timber, unedged timber measurement.