BS 1142:1989

Foreword
Committees responsible
Specification
1. Scope
2. Definitions
3. Dimensional tolerances
4. Flame and fire retardant boards
5. Physical and mechanical properties
6. Marking
Appendices
A. Methods of test
B. Verification of compliance
C. Common uses of fibre building boards in the
     construction industry
D. Recommendations for transportation, storage
     and conditioning of fibre building boards
Tables
1. Permissible deviations in length, width and
     thickness within and between boards of hardboard,
     medium density fibreboard (MDF), mediumboard and
     softboard
2. Summary of test methods and acceptance levels
     given in tables 3 to 6
3. Test levels for hardboard
4. Test levels for mediumboard
5. Test levels for MDF
6. Test levels for softboard
7. Board identification, types and colours of stripes
8. Number of test specimens required when testing
     boards
9. Acceptance levels for postmanufacture batch
     testing for five typical batch sizes
10. Guidance on the use of fibre building boards in
     the construction industry
Figures
1. Subdivision into test pieces
2. Measurement of panel length and width
3. Measurement of edge straightness
4. Measurement of squareness
5. Measurement of length and width
6. Measurement of thickness for density determination
7. Measurement of increase in length
8. Measurement of thickness for dimensional changes
     associated with changes in relative humidity
9. Test rig for determining bending strength
10. Thickness and width determination for bending
     strength test
11. Test rig for measuring deflection
12. Load deflection curve for modulus of elasticity
13. Apparatus for determination of transverse internal
     bond of the board
14. Apparatus for determination of extractable
     formaldehyde
15. Parallel shank screw 38 mm x 4.1 mm with two
     start thread
16. Support for test specimens for determination of
     surface absorption
17. Typical mounting of test specimen for determination
     of recovery and compression

Requirements for hardboard, mediumboard, medium density fibreboard and softboard. Manufacturing requirements concerning permissible deviation on sizes, flame and fire retardant boards, marking requirements and methods of tests specified. Guidance is given on the application of fibre building boards for certain common uses in the construction industry and recommendations made on their transportation, storage and conditioning.