CSL - The Creosote Sweeping Log: a simple and effective solution for cleaning your chimney, while enjoying your fireplace! Creosote Sweeping Log (CSL) burns like a standard fireplace log, while simultaneously reducing dangerous creosote build-up. Great for fireplaces and woodstoves! CSL helps prevent chimney fires if used every 50 fires or at least once a year. CSL is a CSIA (Chimney Safety Institute of America) accepted product and is UL Approved The Creosote Sweeping Log burns for approximately 90 minutes. During that time it heats the tar on your chimney wall to an ideal treatment temperature. The smoke from CSL is charged with minerals, which are deposited onto the creosote over several hours. During the next 15 days, the CSL treatment will continue to work and the creosote will gradually become brittle and break away. Any deposits that remain, will be rendered less flammable. CSL - The Creosote Sweeping Log is designed to work on any kind of chimney, including stainless steel. CSL may also be used in combination wood/oil burning furnaces. CSL - Creosote Sweeping Log For Fireplaces and Woodstoves: Reduces new creosote build-up, making your next fire safer. Burns like a standard fireplace log, while simultaneously cleaning your chimney. Flammable creosote that builds up along the walls of your chimney are neutralized and removed within 2 weeks. CSL action against creosote reduces odors. Minimizes future build-up of creosote. Use every 60 fires for best results. Suitable for both fireplaces and woodstoves. Accepted by the Chimney Safety Institute of America. Burns for up to 2 hours. UL listed product