Towngas is another widely used source of energy in Hong Kong citizens’ everyday lives.
In the afternoon of 16 August 2018, an EMYA ambassador joined a regular gas inspection carried by The Hong Kong and China Gas Company Limited (Towngas) under the monitoring of two EMSD inspectors, Mr. CHAN Chi Kong and Mr. Michael KAN, from EMSD’s Gas Standards Office.
Upon arriving at the entrance of a private estate in Siu Sai Wan, a sizable stainless-steel Governor Kiosk at the side corner on the access road was noticed. The Towngas technician swing opened the two doors to the sides and there situated a set of Gas governors which, according to Mr. KAN, is typically composed of an active governor, a monitoring governor, indicated chart recorder and gas pipes. Gas governors are essential for the safety and reliability of the gas supply system as they regulate the gas pressure by different installation to switch lower, from intermediate (700 to 240KPa) to medium pressure (240 to 7.5KPa), then switch to a lower optimum level (<7.5KPa), when supplying gas to individual buildings, the gas pressure would be switch to appropriate level (<2.0KPa).
Traditional governors is usually larger in size and sometimes visually intrusive, but over the years thanks to the huge engineering efforts of specialists the units now could even be hidden underground to save street space thus become virtually invisible.
However, pedestrians can still grasp an idea of what unseen by observing the colour of the rectangular-shape manhole covers found on the walkways. Yellow-painted one denotes medium pressure pipes while half-yellow ones are low pressure pipes; those underneath the red manhole covers are designed with drainage features. Improvement is also made on the material of the pipe with which iron is replaced by more durable Polyethylene (PE) plastic to reduce the possibility of corrosion. To ascertain the safety and reliability of gas pumping process, every 10 years inner pipes are cleansed by running through a Pigging with blades and censors to collect data along the way.
Our Ambassador listened very attentively to Mr. CHAN who remarked apart from daily inspection, the Gas Standards Office’s scope of work also includes gas incident investigation, approval of gas installations and domestic appliances as well as public education of gas safety.
