The Smoke Density Indicators are used for optical sensing of smoke density across the smoke stack/funnel and remote indication with alarm functions used in Marine Boilers. Symtronics Automation Pvt. Ltd. Offers Smoke Density Indicators for Marine Boilers. Symtronics Automation Pvt. Ltd. Is an ISO 9001-2000 registered organization that supplies electronic controls for Naval applications. The Smoke Density Indicators are used for improvement of boiler fuel efficiency and environmental control.