Safety system

Safety System of Flue Gases

There is usually wrong usage of gas appliances behind accidents and gas poisoning


Search for indication B11BS

Key safety part of gas chimney´s appliance is safety system of flue gases. This system monitors whether flues from heater safely come to chimney. If it is not like that, flues come back to room, a burner of appliance will turn off. Usually bad flue outlet is the main cause of intoxication and choking.The appliances equipped with safety flue gas system are labelled as a version B11BS. Only boilers and water heaters with this indication are allowed to be used in residential buildings.

The gas appliances indicated as B11 dont have safety system of flue gases on the other hand. Neither legislation nor technical standards dont forbid appliances without safety system of flue gases. There must be notification (on the cover and in the technical documentation) about restriction that these appliances can be used only in well ventilated rooms separated from residential buildings. The appliances type B11 are designed for exterior usage.


Don´t forget to check chimney´s technical conditions of gas appliances

The chimney´s conditions is one of the key factors for safe maintanence of gas appliances. There is a lot of people who underestimate regular chimney inspections. This group of people think there is no point to check chimney unless you use boiler for solid fuel. It is not like that. Usually stacked chimney is cause of many poisonings. The solution is easy – regular chimney inspections by qualified chimney sweeper.

And of course all appliances should be regularly checked. Only about 30% of appliances are regularly serviced and checked according to our experience.

What you can do to ensure safe use of your gas appliance:

  • Ensure required ventilation in the room in which the appliance is placed.
  • Be aware when changing old windows for new one´s (tighter) – there always must be some air -necessary for the appliance!
  • Be aware when choosing various gas water heaters! The appliances idicated as B11BS have safety flue gas system whereas appliances indicated B11 dont have it.
  • Keep appliance in good shape and get it checked by proffesional specialists!
  • If possible place appliance into technical room but not into bathroom! Appliances indicated B11 are suitable only into well ventilated technical room!
  • Keep eye on chimney´s conditions! Standard regular review by chimney sweeper should be necessary!

15–30 minutes

This is usually the time for which human would die in the closed bathroom with 4 square metres.

The intoxication itself doesnt last long. The signs of intoxication are a headache, sickness, disability to leave contaminated space. During heavy intoxication the body gets into deep faintness. According to the doctors there can a brain death in this stage. There can be neurological symptoms despite a patient being saved.

Carbon monoxide is a toxic gas which is adhesive to hemoglobin. The adhesion is 200 times stronger than oxygen therefore its removal from blood take a lot of hours, days.The cells cant live without oxygen and dies quickly, at most in nerve and brain cells. As a result of that, the patients usually have disabled brain or death brain after intoxication of carbon monoxide.

The most common situation is during long having shower when water warms up in gas flow heater and produces more toxic fumes.