(SEE PARAGRAPHS 1.36 AND 1.54)
E1 This Appendix describes ways of checking the compliance with J2 of existing, relined or new flues, and (where included in the work) the combustion appliance. It applies only
to natural draught flues intended for open-flued appliances. The procedures described are used only to assess whether the flue in the chimney, the connecting fluepipe (and flue gas passages in the appliance) are free of obstruction and acceptably gas-tight. In addition, appliance performance tests, including flue spillage tests to check for compliance with J2, should be carried out when an appliance is commissioned
to check for compliance with Part L and as required by the Gas Safety (Installation and Use) Regulations.
E2 Tests on flues should be carried out at the most appropriate time during the building work. Where possible, for example, smoke tests should be performed when the structure of a chimney is visible and before the application of finishes such as plaster or dry lining that could obscure sight of smoke leakage during testing.