Library materials are exposed to various biological agents that cause serious deterioration and shorten their useful life. Among these, book pests such as insects and rodents are particularly harmful. They attack paper, bindings, adhesives, leather, cloth and other organic materials used in books and manuscripts. Warm temperature, high humidity, poor ventilation, darkness, dust and unhygienic storage conditions encourage the growth and multiplication of these pests in libraries. Silverfish are among the most common pests found in libraries. They feed on carbohydrates and substances containing starch, which are present in paper, book bindings and adhesives. They scrape the surface of paper and produce irregular holes and patches, especially along the edges of pages. Their activity can make printed matter illegible and weaken the paper considerably. Cockroaches are another major threat to library collections. They feed on paper, glue, book cloth and other organic materials. They gnaw and stain pages, leaving irregular holes, damaged edges and unpleasant secretions. Their excreta and body fluids produce stains and may encourage microbial growth. Cockroaches also carry