Purpose: This document provides technical information for the design and construction of ash pits for small-scale medical waste incineration. In many national jurisdictions and the international Basel Convention, this ash is defined as hazardous waste because of its hazardous chemical content and ability to cause harm. As a result, it should ideally be disposed of in a properly engineered hazardous waste landfill. However, wherever small-scale medical waste incineration is being carried out, there is unlikely to be access to any such landfill. In this event, an ash pit is essential to prevent uncontrolled disposal of the ash, which can allow the contaminants it contains to enter the environment or the food chain.