Dear Vijay, These are some procedures which we are following in our Library and getting best results.I wish you these are simple and you might have tried. * First Library should be broomed daily and floor dusting with funnel and little soap should be applied twice in a week. * If more rats are destroying your clloection you may keep Mortin cake at the weekend and careul in searching the books on Monday that is start of the week.Mostly they eat this cake and die not immediately but in one or two days and they generally come in open space.But be attentive. * A personnel care is must for a Library. * Use napthalene balls at each corners, racks, cupboards and shelves. * Good light and ventelation if possible. * Harble Vekhand powder or stick may be kept to avoid germs. * To remove dust either use euroclean twice in a week or outsource some good worker once in a month for physical cleaning Kshipra