Hair Conditioners are used to make hair smooth and silky. They help by replacing materials, such as natural oils, lost during washing. The safety of Hair Conditioners is established by selection of ingredients that are safe and suitable for this purpose. In addition, Hair Conditioner Products are assessed for their potential to cause scalp and eye irritation. Product safety is also ensured though strict adherence to the principles of Quality Assurance and Good Manufacturing Practices. This includes testing the compatibility of the product with packaging as well as shelf-life stability. The FDA recommends that Hair Conditioners be assessed to determine the type and degree of eye irritation that may occur, and to assure that products are not contaminated and will not become contaminated during normal use. The FDA also recommends that directions on the label be followed and that these products be used in a safe manner. Finally, the safety of products is monitored in the market-place through reports of consumer comments and complaints. Companies include a phone number on their products where comments or complaints may be reported.