The decorative pattern on the ceramic surface can become scratched and marred with use, depending upon maintenance, but does not adversely affect performance. Such blemishes are not covered by the warranty and do not affect the operation of the hob. Spills and melts must be removed immediately, while the surface is still warm, using the scraper supplied with the unit. Especially damaging are melted plastic, aluminum, or any foodstuff containing sugar, including natural sugar, as these can create permanent �pockmarks� and craters on the ceramic surface. After scraping polish thoroughly with the cleaning agent supplied with the unit. Utensils which have been in contact with the above-mentioned melted materials must be cleaned throughly before used again on the ceramic-top hob unit. Defects in the ceramic surface which can be related to the above are not covered by the warranty. Warning: Aluminum foil and plastic utensils are not to be placed on hot surfaces. The surface may not be used for storage. Do not stare at the heating units when in operation.