The main purpose of laboratory tests is to obtain prior knowledge of the performance of textile products in service. The assumption is made that when such tests are carried out, there is some relationship between the results of the laboratory tests and the performance of the items in use. In order to design laboratory testing procedures that correlate with end use performance the conditions of actual use must be carefully analysed so that they can be simulated as closely as possible in a controlled setting. Since actual wear is such a complex phenomenon, however, laboratory tests are usually designed to evaluate only one or a limited number of variables at a time.
Advantages of Laboratory Tests
- They are rapid. Most tests can be completed within a day.
- They are designed to give objective results. A numerical result or rating allows one fabric to be ranked as being better or worse than another fabric even when the differences between them are small.
- The tests are under the direct control of the tester. This allows the conditions of test to be exactly specified and factors other than those under test to be kept constant.
- They can be reproduced. An identical test carried out on the same fabric should ideally give the same result in any laboratory and with any operator.
- Laboratory tests can only imitate wear conditions
- For a complete evaluation of a fabric it is necessary to use a large range of expensive equipment.
- Laboratory tests are rapid because many of them aim to accelerate the natural causes of wear. Speeding up a test may give false results, for example the continuous action of abrasion tests may cause heating of the material which is not present in normal use.