What do the numbers in grade 85/25 mean?

85 refers to the average softening point in °C, and 25 refers to the average penetration at 25°C (in 1/10th of a mm).

Which grades are typically used for general roof waterproofing?

Grades 85/25 and 90/15 are most commonly used for built-up roofing and standard damp-proofing applications.

What tests are mandatory to verify industrial bitumen quality?

Key tests include Softening Point (IS 1205), Penetration (IS 1203), Ductility (IS 1208), Flash Point (IS 1209), and Loss on Heating, as outlined in Table 1.

IS 702

: 1988

Industrial Bitumen - Specification

SupersededSpecializedSpecificationMaterials Science · Waterproofing and Damp Proofing

Superseded by IS 702:2017

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This standard specifies the requirements and methods of testing for industrial bitumen primarily used for waterproofing, damp-proofing, and pipeline protection. It classifies industrial bitumen into grades based on their softening point and penetration characteristics.

Specified requirements for different grades of industrial bitumen for various applications, including waterproofing, before the 2017 revision.

Quick Reference Values

Grade 85/25 Softening Point80 to 90 °C

Grade 85/25 Penetration20 to 30 at 25°C

Grade 90/15 Softening Point85 to 95 °C

Grade 115/15 Softening Point110 to 120 °C

Grade 135/10 Softening Point130 to 140 °C

Solubility in Trichloroethylene (Min)99.0 % by mass

Practical Notes

Industrial bitumen grades are designated by two numbers: the first represents the average softening point and the second represents the average penetration.

Overheating industrial bitumen during application can alter its properties, leading to brittleness and loss of waterproofing capabilities.

Always ensure compatibility of the bitumen grade with the specific climatic conditions, surface requirements, and expected thermal movements.