Changes to Gas Boiler Safety Checks
Where existing flue ventilation systems are concealed within a void and cannot be visually inspected, steps will have to be taken to fit inspection hatches by 31st December 2012. Where visual inspection after that date is impossible Gas Safe registered engineers will declare that the system is unsafe to use.
From the mid-1990s fan assisted flues became available and many new-build and refurbished properties were fitted with boilers on internal walls in order to make better use of the available space. Often these flues travelled significantly greater distances than was previously the case to terminate at an external wall, necessitating in some cases a number of joints in the flue run.
The latest HSE Safety Notice (which came into force on 1st January 2011) is an update of the October 2008 notice which was issued to raise awareness of the potential dangers from certain types of flues connected to gas central heating installations that may not have been installed properly, or may have fallen into disrepair (so that the integrity of the flue was affected allowing carbon monoxide to escape into living space).
Where boilers are located away from external walls, flues are more likely to run through ceiling (or wall) voids. In such cases when the gas appliance is serviced or maintained it can be difficult, or impossible, to determine whether the flue has been installed correctly or whether it is still in good condition.
Where a flue fault exists in combination with a boiler which is not operating correctly, deadly levels of carbon monoxide can build up and be released back into the accommodation. According to HSE statistics around 20 people die each year from carbon monoxide poisoning caused by gas appliances and flues that have not been properly installed, maintained or that are poorly ventilated. Others suffer serious damage to their health. Carbon monoxide is colourless, odourless, tasteless and highly poisonous.