Rarely should more than one copy of a title be purchased. With the exception of classic works in such general areas as anatomy, nursing and first aid, most selections in the medical sciences should be aimed at the general consumer. It is important to cover as wide a range of diseases and treatments as possible. Coverage of the more popular subjects in these areas needs to be broad in terms of level, from beginner to professional. Other subjects, especially some in the 660s, 670s and 680s, are too specialized and technical for a public library this size, in which case only popular works aimed at the non-professional are appropriate.
Broad coverage is especially important in car repair books in terms of both year and model.
This is especially true for books on specific diseases. In other areas, such as dieting, smoking cessation, etc., weeding should be based more on usage level. While it is necessary to select a wide range of books in such areas, their popularity often drops quickly after a year or two. In all areas, retention should be based on usage level and accuracy of information. Single-model books should be retained as long as the model is popular, or a minimum of 5 years.