ASTM D56 standard test method for flash point by Tag closed cup tester
1. Scope
1.1 This test method covers the determination of the flash point, by tag manual and automated closed testers, of liquids with a viscosity below 5.5 mm2/s (cSt) at 40°C (104°F), or below 9.5 mm2/s (cSt) at 25°C (77°F), and a flash point below 93°C (200°F).
1.1.1 For the closed-cup flash point of liquids with the following properties: a viscosity of 5.5 mm2/s (cSt) or more at 40°C (104°F); a viscosity of 9.5 mm2/s (cSt) or more at 25°C (77°F); a flash point of 93°C (200°F) or higher; a tendency to form a surface film under test conditions; or containing suspended solids, Test Method D93 can be used.
1.1.2 For cut-back asphalts refer to Test Methods D1310 and D3143.
NOTE 1 - The U.S. Department of Transportation (RSTA)2 and U.S.
Department of Labor (OSHA) have established that liquids with a flash point under 37.8°C (100°F) are flammable as determined by this test method for those liquids that have a viscosity less than 5.5 mm2/s (cSt) at 40°C (104°F) or 9.5 mm2/s (cSt) or less at 25°C (77°F), or do not contain suspended solids or do not have a tendency to form a surface film while under test. Other flash point classifications have been established by these departments for liquids using this test method.
1.2 This test method can be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and cannot be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test method can be used as elements of fire risk assessment that takes into account all of the factors that are pertinent to an assessment of the fire hazard of a particular end use.
1.3 Related standards are Test Methods D93, D1310, D3828, D3278, and D3941.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements see 8.2, 8.3, 9.5, 12.5, and refer to Material Safety Data Sheets.
2. Referenced Documents
2.1 ASTM Standards:
D93 Test Methods for Flash Point by Pensky-Martens Closed Cup Tester
D1310 Test Method for Flash Point and Fire Point of Liquids by Tag Open-Cup Apparatus
D3143 Test Method for Flash Point of Cutback Asphalt with Tag Open-Cup Apparatus
D3278 Test Methods for Flash Point of Liquids by Small Scale Closed-Cup Apparatus
D3828 Test Methods for Flash Point by Small Scale Closed Cup Tester
D3941 Test Method for Flash Point by the Equilibrium Method with a Closed-Cup Apparatus
D4057 Practice for Manual Sampling for Petroleum and Petroleum Products
D6299 Practice for Applying Statistical Quality Assurance Techniques to Evaluate Analytical Measurement System Performance
D6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and Lubricants
E1 Specification for ASTM Liquid-in-Glass Thermometers
E502 Test Method for Selection and Use of ASTM Standards for the Determination of Flash Point of Chemicals by Closed Cup Methods
2.2 Federal Test Method Standards:
Method 1101, Federal Test Method Standard No. 791b
Method 4291, Federal Test Method Standard No. 141A
2.3 ISO Standards:
Guide 34 General Requirements for the Competence of Reference Material Producers
Guide 35 Certification of Reference Materials - General and Statistical Principles
3. Terminology
3.1 Definitions:
3.1.1 flash point - the lowest temperature corrected to a pressure of 101.3 kPa (760 mm Hg) at which application of an ignition source causes the vapors of a specimen of the sample to ignite under specified conditions of test.
3.1.1.1 Discussion - The specimen is deemed to have flashed when a flame appears and instantaneously propagates itself over the entire surface of the fluid.
3.1.1.2 Discussion - When the ignition source is a test flame, the application of the test flame may cause a blue halo or an enlarged flame prior to the actual flash point. This is not a flash and should be ignored.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 dynamic (non-equilibrium) - in this type of flash point apparatus, the condition of the vapor above the specimen and the specimen are not at the same temperature at the time that the ignition source is applied.
3.2.1.1 Discussion - This is primarily caused by the heating of the specimen at the constant prescribed rate with the vapor temperature lagging behind the specimen temperature. The resultant flash point temperature is generally within the reproducibility of the test method.
3.2.2 equilibrium - in that type of flash point apparatus or test method, the vapor above the specimen and the specimen are at the same temperature at the time the ignition source is applied.
3.2.2.1 Discussion - This condition may not be fully achieved in practice, since the temperature is not uniform throughout the specimen and the test cover and shutter are generally cooler.
