Foreword
1 Scope
2 Normative references
3 Product shape
      3.1 General
      3.2 Straight flue blocks
      3.3 Form
4 Definitions
5 Classes of flue block
6 Materials
      6.1 Flue blocks
      6.2 Insulation
7 Tolerances on dimensions
      7.1 Internal transverse dimensions
      7.2 Height
      7.3 Angles
      7.4 Straightness
      7.5 Squareness of angles and flatness of walls
      7.6 Deviation from shape of cross-section
      7.7 Joints
      7.8 Bonding extension
      7.9 Tolerance on insulation thickness
8 Proof load
      8.1 Straight flue blocks
      8.2 Angle blocks
      8.3 Minimum load for inspection opening sections
      8.4 Adhesion between outer wall and insulation
9 Gastightness (leakage test) and thermal testing
      9.1 Initial test
      9.2 Final gastightness (leakage test) after thermal
             testing
10 Acid resistance
11 Water absorption and bulk density
      11.1 General
      11.2 Water absorption
      11.3 Bulk density
12 Sweeping resistance
13 Water and vapour flow resistance
14 Thermal resistance
15 Fire resistance
      15.1 Testing at operating conditions
      15.2 Soot fire test
16 Evaluation of conformity
      16.1 Sampling and testing
      16.2 Sampling for quality control at the
             manufacturer's works
      16.3 Sampling for resubmitted rejected batches
      16.4 Type tests
      16.5 Quality assurance
17 Test methods
      17.1 Internal transverse dimensions
      17.2 Height
      17.3 Angles
      17.4 Straightness
      17.5 Squareness of ends
      17.6 Deviation from shape of cross-section
      17.7 Proof load
      17.8 Thermal testing
      17.9 Acid resistance
      17.10 Water absorption
      17.11 Bulk density
      17.12 Sweeping resistance
      17.13 Water and vapour flow test
      17.14 Fire resistance
      17.15 Determination of bulk density of insulation
      17.16 Adhesion test for insulation attached to outer
             wall of flue blocks
18 Designation
19 Marking
Annex A (normative) Sampling procedures for an AQL of 10% and
                    Inspection Level S2
      A.1 - Acceptability determination
      A.2 - Normal inspection
      A.3 - Normal to reduced inspection
      A.4 - Reduced to normal inspection
      A.5 - Tightened inspection
      A.6 - Tightened to normal inspection
      A.7 - Discontinuation of inspection
Annex B (informative) Thermal resistance
      B.1 - Method 1
      B.2 - Method 2 - Thermal resistance of flue blocks with
            or without cavities
      B.3 - Method 3 - Approximate thermal resistance values
Annex C (informative) Prevention of fire spread
National Annex NA (informative) Recommendations for design
                                and construction of clay flow
                                block systems