ABSTRACT
The lter fabrics are made out of natural or synthetic materials using various woven or nonwoven fabric structures. These fabrics are used in various industrial applications in automobile, medical, air ltration, water ltration, etc. According to the end-user requirements, the test requirements will vary. Some of the important tests required for the lter fabrics are as follows:
1. Filter fabrics (Woven type) a. Mass per square meter (ASTM D: 5261/ASTM D: 3776/ISO: 9864/
IS: 14716) b. Thickness (ASTM D: 5199) c. Thread density (ASTM D: 3775/IS: 1963) d. Yarn number (IS: 3442/ASTM D: 3883) e. Tear resistance (trapezoid strength) (ASTM D: 4533/IS: 14293) f. Grab strength (ASTM D: 4632/ISO: 13934/2) g. Water permeability (ASTM D: 4491/BS: 6906/3/IS: 14324/ISO:
11058) h. Air permeability (ASTM D: 737) i. Pore size by porometer (ASTM D: 6767) j. Apparent opening size (ASTM D: 4751) k. Bursting strength (ASTM D: 3786/IS: 1966) l. Breaking strength and elongation (ASTM D: 5035/DIN EN ISO:
13934/1) 2. Filter fabrics (Nonwoven type) m. Mass per square meter (ASTM D: 5261/ASTM D: 3776/ISO: 9864/
IS: 14716) n. Thickness (ASTM D: 5199)
o. Tear resistance (trapezoid strength) (ASTM D: 4533) p. Breaking strength/grab strength (ASTM D: 4632) q. Water permeability (ASTM D: 4491/BS 6906/3/IS: 14324/ISO:
11058) r. Air permeability (ASTM D: 737) s. Pore size by porometer (ASTM D: 6767) t. Apparent opening size (ASTM D: 4751) u. Bursting strength (ASTM D: 3786/IS: 1966)
12.1.1 Testing of Filter Media
A large and ever-increasing number of standard tests are available for characterizing either lters or their associated media. These standards are established either by national authorities, such as the British Standards Institution and the American Society for Testing Materials (ASTM), by specic industry organizations, such as TAPPI (the American Pulp and Paper Industry), or by regional or international organizations, such as Comit European de Normalization and the International Organization for Standardization (ISO).
12.1.2 Testing Filtration Characteristics
