THE DEVELOPMENT OF A COMPARATIVE METHOD FOR THE EVALUATION OF THE MOTH-PROOFNESS OF WOOL SERGE

Existing test methods for the moth-proofness of wool were compared in inter-laboratory experiments and found to be lacking in accuracy and agreement between laboratories.
Several factors influencing the usefulness of such a test method were investigated, and it was found that a considerable gain in accuracy could be reached if weight loss due to larval attack on test samples was referred to weight loss obtained with a standard wool serge impregnated with a standard moth-proofing substance. Apart from this principle, improvements in the general testing procedure, including the number of test samples and test animals used, the definition of weight loss and the introduction of strict randomization procedures proved to be valuable.
As a provisional reference standard, wool serge impregnated with dinitro-α-naphthol was adopted. A tolerance level for the moth-proofness of wool serge was laid down.