EnergySafe Magazine Autumn 2015, issue 39 - Page 24

24 Gas Q&A  gas Your questions answered! Compiled by ESV’s Gas Installations and Appliance Safety team. As per previous issues of Energysafe, we are pleased to provide answers for a varied range of frequently asked questions received on ESV’s Gas Technical Helpline, 1800 652 563. Note The technical regulator may require notification before work commences and confirmation that completed work is in accordance with this Standard (AS 5601—2013) and any other relevant requirements. Question Answer Clause What is the maximum temperature a combustible surface is allowed to reach from heat transmitted by a gas appliance? The surface temperature of a combustible surface, from heat transmitted by a gas appliance, shall not exceed 65° C. AS/NZS 5601.1:2013 How are clearance distances between a gas cooking appliance and the surrounding combustible surfaces determined? The required clearance distances between a gas cooking appliance and a combustible surface is always in accordance with the requirements as set by the cooking appliance manufacturer. AS/NZS 5601.1:2013 If the manufacturer does not specify clearance distances then clearances shall be as specified in the Standard AS/NZS 5601.1:2013 section 6.10 Additional requirements for installation of specific gas appliances. What is the overhead clearance distance above a cooking appliance for range hoods and exhaust fans where the manufacturer has not specified that distance? Vertical clearance distance for a range hood is not less than 600mm; measured from the top of the highest burner to the base of the rangehood. Vertical clearance distance for an exhaust fan is not less than 750mm; measured from the top of the highest burner to the base of the exhaust fan. Should any other downward facing combustible surface be less than 600mm above the top of the highest burner then the whole of the combustible surface shall be protected for the full width and depth of the cooking surface as described in AS/NZS 5601.1:2013 Appendix C Fire resistant material. 6.2.5 Temperature limitation on nearby combustible surface 6.10.1.1 Clearance around a gas cooking appliance AS/NZS 5601.1:2013 6.10.1.1 Clearance around a gas cooking appliance (a) Requirement 1—Overhead clearances The absolute minimum clearance height distance for any surface above the highest part of the highest burner is 450mm. What is the side clearance (horizontal) distance from a cooking appliance to a vertical combustible surface and the height to which the combustible surface must be protected? The horizontal clearance distance from the edge of the nearest burner to any vertical combustible surface shall not be less than 200mm. The height to which the combustible surface must be protected shall not be less than 150mm. This height is measured from the top of the highest burner. Where the horizontal clearance distance cannot be achieved the combustible surfaces shall be protected for its full width and height as described in AS/NZS 5601.1:2013 Appendix C, Table C1. AS/NZS 5601.1:2013 6.10.1.1 Clearance around a gas cooking appliance (b) Requirement 2— Measurements If the gas cooking appliance is fitted with a splashback the protection of the rear wall is not required so long as the splashback achieves the same protection for any combustible surface less than 200mm from the edge of the nearest burner to a height not less than 150mm above the top of the edge of the nearest burner. What clearance distances (horizontal and vertical) are required for a freestanding and elevated gas cooking appliance when that appliance is situated next to a horizontal combustible surface, such as a bench, that (a) is below the hob or (b) above the trivet? The horizontal clearance distance from the edge of the nearest burner to the edge of any horizontal combustible surface should be 200mm or greater. (a)  here the horizontal clearance distance is less than 200mm then the W distance below the hob of the combustible surface shall be 10mm or greater. A clearance of less than 10mm below the hob to the horizontal combustible surface is not permitted without fully protecting the combustible surface as described in AS/NZS 5601.1:2013 Appendix C, Table C1. (b)  here the horizontal clearance distance is less than 200mm and the W top of the horizontal combustible surface is above the top of the trivet the exposed vertical combustible surface must be protected as described in AS/NZS 5601.1:2013 Appendix C, Table C1. AS/NZS 5601.1:2013 What are the clearance distances for barbecues (approved for indoor installation) that comply with the requirements of domestic cookers and are used in residential premises? Minimum clearance distances from a cooking surface: »» vertically to an overhead grease filter is 1200mm »» vertically to a combustible surface is 1200mm »» vertically to a non-combustible surface is 600mm »»  orizontally to a vertical combustible surface is 200mm. h (However for horizontal distances less than 200mm the vertical combustible surface must be protected as described in AS/NZS 5601.1:2013 Appendix C, Table C1.) AS/NZS 5601.1:2013 6.10.1.1 Clearance around a gas cooking appliance (c) Requirement 3—additional requirements for freestanding and elevated cooking appliances 6.10.1.7 Barbecues in residential premises