Overview
ISO 26985:2008 specifies laboratory methods for the identification of linoleum and for determination of linoleum cement content and ash residue in resilient floor coverings. The standard is intended for material verification, quality control and regulatory compliance in manufacturing, testing laboratories and procurement.
Key procedural elements include saponification for identification, chemical dissolution and filtration to quantify organic binder (linoleum cement), and controlled incineration to measure inorganic ash residue.
Key Topics
- Identification of linoleum
- Small specimens are saponified in a potassium hydroxide (KOH) in methanol solution. Complete disintegration within 24 h indicates linoleum.
- Cement content (linoleum binder)
- Remove backing, grate the specimen and use material passing a 0.5 mm sieve.
- Treat ~1 g grated specimen with KOH/methanol (analytical grade; KOH in methanol solution given in the standard) with stirring at 20–25 °C for the specified time.
- Filter/centrifuge, dry and weigh the residue. Cement content is calculated as: (m1 − m2) / m1 × 100, where m1 is initial specimen mass and m2 the dry residue mass.
- Ash residue (inorganic filler content)
- Remove backing and incinerate a crumbled specimen in a porcelain crucible at 500 ± 10 °C for at least 3 h.
- After cooling in a desiccator, weigh the ash. Ash residue is calculated as: m3 / m1 × 100, where m3 is ash mass and m1 the initial specimen mass.
- Sampling and conditioning
- Take five representative specimens (minimum area 50 cm² each or individual tiles), cut approximately 20 mm × 20 mm squares and condition at 23 ± 2 °C and 50 ± 5 % RH for at least 24 h prior to testing.
- Apparatus & materials
- Examples include: grater, 0.5 mm sieve, tared beakers, porcelain crucibles, furnace (500 °C ± 10 °C), desiccator, balance (0.1 mg accuracy), ultrasonic bath, centrifuge/vacuum filter, methanol (analytical) and KOH solution.
Applications
- Quality control of linoleum production and finished floor coverings.
- Material verification for renovation, historical preservation and product compliance.
- Regulatory and procurement testing where accurate binder and filler content are required for specification or certification.
Practical benefits include standardized test results that support reproducible laboratory reporting and clear pass/fail identification of linoleum in mixed flooring products.
Related Standards
- EN 670 - Equivalent European standard referenced in ISO 26985:2008.
- ISO/TC 219 - Technical committee responsible for floor coverings.
Test reports under ISO 26985:2008 should state conformity to the standard, product identification, sample history, whether the sample is identified as linoleum, average cement and ash percentages, any deviations, and test date.