A Case Study In Gas Building Solutions From IGD
Boiler House Case Study
A UK company approached IGD to look at possible solutions to gas detection issues following a potentially serious incident on one of their sites.
Initially the enquiry related to boiler plant rooms however when IGD began surveying a number of these sites they found that as the companies property portfolio was mostly older buildings upgrades and additions to original use had further increased gas hazard risks.
These sites originally had oil fired boilers in basement plant rooms which had now been converted to natural gas multi-boiler packs; in some cases the only protection was the original thermal links which although useful for solid/liquid fuel fires are of no use for gas leak detection.
The boiler flues passed through a number of upper floors before venting to atmosphere. This arrangement had caused issues on a number of sites where the flue system had failed allowing products of combustion into both plant rooms and offices.
Some sites also had staff kitchens and underground service tunnels bringing electrical cables and services into the sites. Some of these service tunnels when surveyed reported Hydrogen Sulphide readings from gases leaching in from local underground dry river beds and in one case a landfill site where Methane and CO2 was also detected.
On most sites monitoring had been added in a piecemeal fashion over a number of years without any overall consideration of what was required for the site as a whole.
- Gas hazards recorded and considered during survey comprised:
- Natural Gas (Methane) as a fuel gas in Kitchen areas and boiler plant rooms
- Carbon Monoxide and Carbon Dioxide as products of combustion from the boiler plant and kitchens
- Hydrogen Sulphide, Carbon Dioxide and Methane in service tunnels leaching from external sources
The sites required a comprehensive integrated gas detection system. IGD proposed their Tocsin 920 addressable gas detection control panel and TOC-30 Series addressable gas detectors. This approach minimised cabling and site disruption as the addressable detectors could be networked onto single cable runs along with I/O modules for alarms. The 920 system controller could be easily monitored off site centrally as each could be fitted with a GSM module. this was especially important as a number of sites had only partial occupancy.
CO2 and CO detectors were installed into rooms where boiler flues passed through. Kitchen areas were fitted with CO2 detectors to ensure correct ventilation and Methane detectors (natural gas) to detect any release of potentially explosive gas from unlit hobs. In addition the controller was linked to the kitchen gas supply to shut down in the event of gas detection or on a signal integrated from the fire panel on the site.
Boiler rooms were fitted with Methane and CO detectors and again linked to the gas supply to shut off in the event of gas detection or a signal integrated from the site fire detection panel.
Hydrogen Sulphide, Carbon Dioxide and Methane detectors were fitted to the underground service tunnels to continuously monitor leaching gases. The 920 control panel controlled ventilation rates to these areas to both minimise energy use whilst ensuring effective ventilation.
The overall system incorporated clear alarms in each area using IGD’s addressable annunciators and addressable beacon sounders. This ensured clear zoned alarming on detection of gas