BS EN 60754-1:2014 pdf free
BS EN 60754-1:2014 pdf free.Test on gases evolved during combustion of materials from cables Part 1: Determination of the halogen acid gas content.
The material under test shall be heated in a stream of dry air and the gases shall be absorbed in 0,1 M sodium hydroxide solution contained in wash bottles. The amount of halogen acid shall then be determined by acidifying the solution with nitric acid, adding a measured volume of 0,1 M silver nitrate solution and back titrating the excess with 0,1 M ammonium thiocyanate, using ferric ammonium sulphate as the indicator.
NOTE I Other analytical methods having at least the same precision may be used, but in case of dispute the method given In this standard is the one to use.
NOTE 2 Although both hydrogen chloride and hydrogen bromide are detected by this analytical method, the halogen acid Content is reported as if all the halogen acid is hydrogen chloride.
5 Test apparatus
5.1 General
The apparatus is shown in Figures 1 to 5.
The assembly of the components which constitute the test apparatus shall be leak-tight. The connecting distances between the quartz glass tube and the first bottle and between subsequent bottles shall be as short as possible. Glass or silicone rubber tubing shall be used for these connections.
NOTE 1 At the exit side of the quartz glass tube, as close to the end as possible, it is permitted to place a plug of silica wool to aid collection of condensates.
NOTE 2 A third empty bottle, of the same size as the gas washing bottles, placed before the gas washing bottles, may be used to improve safety, l.e to prevent suck back of water into the quartz glass tube
5.2 Tube furnace
The length of the heating zone of the furnace shall be within the range 480 mm to 620 mm, and its inside diameter shall be within the range 38 mm to 62 mm. It shall be equipped with an adjustable electrical heating system.
5.3 Quartz glass tube
For the test, a quartz glass tube shall be introduced into the tube furnace. The tube shall be approximately concentric to the furnace, It shall be resistant to the action of corrosive gases.
The inside diameter of the tube shall be within the range 30 mm to 46 mm. The tube shall protrude on the entrance side of the furnace by a length of between 60 mm to 200 mm, and on the exit side by between 60 mm to 100 mm. The initial clearance shall allow for thermal expansion. For the purposes of measurement of the protrusion distances, the tube shall be regarded as that part of essentially constant diameter.
NOTE The outer diameter 01 the tube should be chosen with due regard to the Inside diameter of the tube furnace
Prior to each test, the tube shall be cleaned throughout its length by being calcined at approximately 950 9C.
5.4 Combustion boats
The combustion boat shall be made of porcelain, fused quartz or soapstone and shall have the following dimensions:
— external length: within the range 45 mm to 100 mm.BS EN 60754-1 pdf download.
