This test method is for the determination of total sulfur in combustible fuel gases and is applicable to natural gases, manufactured gases, mixed gases, and other miscellaneous gaseous fuels. For the use of barium chloride titration following collection of sulfur dioxide by alternative procedures, ammonia, amines, substances producing water soluble cations, and fluorides will interfere with the titration. The apparatus includes the following: (1) burner, (2) chimneys, absorbers, and spray traps, (3) flow meter, (4) vacuum system, (5) air-purifying system, and (6) monometer. The schematic diagrams of the gas burner, combustion and absorption apparatus, suction system, and purified air system are provided. Reagent grade chemicals shall be used in all tests and include: (1) water, (2) denatured ethyl or isopropyl alcohol, (3) barium chloride, standard solution, (4) hydrochloric acid, (5) hydrogen peroxide, (6) iso-propanol, (7) potassium hydrogen phthalate, (8) phenolphthalein, (9) methyl orange indicator solution, (10) silver nitrate solution, (11) sodium carbonate solution, (12) sodium hydroxide solution, (13) sulfuric acid, (14) tetrahydroxyquinone indicator, and (15) thorin indicator. The procedure for the following are detailed: (1) calibration and standardization of sodium hydroxide, sulfuric acid, and barium chloride solutions, (2) preparation of apparatus, (3) sulfur determination, (4) analysis of absorbent, and (5) quality assurance. The formula of calculating the volume of gas in standard cubic feet burned during the determination and the concentration of sulfur from the results of titration are given.

1.1 This test method is for the determination of total sulfur in combustible fuel gases, when present in sulfur concentrations between approximately 25 and 700 mg/m³ (1 to 30 grains per 100 cubic feet). It is applicable to natural gases, manufactured gases, mixed gases, and other miscellaneous gaseous fuels.

1.2 The values stated in inch-pound units are to be regarded as standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.