By Sonjib Banerjee
Duval Messien technical director Sonjib Banerjee stresses on earthing in older buildings.
The importance of effective earthing is often overlooked, especially in older residential neighborhoods, warehouses and industrial complexes.
Faulty electrical wiring, low-quality appliances and poorly maintained earthing pits are the main causes of electrical fires.
Fires in older neighborhoods and warehouses in the city may be linked to poor adherence to basic protocol for electrical fault prevention including proper earthing, such as those applicable in the EU which stringently enforces maintenance protocols.
The most common myth is that earthing is a one-off installation procedure, which is incorrect - earthing needs to be maintained regularly according to international standard. During the hot summer months, older residential neighborhoods with high density living, warehouses, souqs and labor camps are most at risk as a single spark can spread rapidly and cause significant damage to life, assets and livestock.
The role of the regulatory bodies like Dubai Electricity and Water Authority, Abu Dhabi Electricity and Water Authority, Ministry of Civil Defense and corporations like are of spear leaders to bring a sea change in safety practices in the country. The recent safety drive by Dubai Municipality and Ministry of Civil Defense is encouraging. There is much scope for incorporation of safety parameters with respect to lightning protection and earthing.
The issue of electrical safety impacts the community at large including the environment. The intelligent community needs to be more aware of each component of safety, options available, and how electrical faults are filtered, collected, transmitted and dissipated.
Though there is meager post Tsunami climate data, the climate report (2008) from Dubai Metrological Office revealed the average temperature from May to July 2008 as 47.1 degree Celsius (117 degree Fahrenheit).
Also, there is no rainfall in the month of June, August and September and the mean rainfall is only 7.38mm only. In such climatic conditions the traditional earth pits are most likely to fail to disseminate charge to the ground during an electrical fault situation.
In such circumstances, the MCB's can fail to function or perform delayed functioning and electrical fires may happen. Use of proper electrical accessories like 3-pin plugs and sockets, branded circuit breakers, use of Terec+ earthing compound, etc. are precautionary measures against electrical fire hazards. Occurrence of fire incidents, as reported in the media, is a matter of concern to one and all.
Adequacy of electrical safety of structures is defined in various international codes. The structures in Dubai need to follow these codes without compromise. The implication of such compromise may directly affect safety of life and asset.
Over and above it also involves understanding its effect on surrounding and environment. In the wholesome concept of electrical safety system, buildings in Dubai like all parts of the world must adhere to proven standards. Currently we believe there may be a need to re-evaluate some areas of concern, based on latest available technology and proven science.
It is an illusion that Dubai is not vulnerable to lightning strikes. Refer to the latest lightning strike that hit Burj Dubai Tower on November 26, 2008. Pictures of lightning strike across the UAE published in newspapers and internet highlights the vulnerability of tall structures against lightning strikes. These evidences confirm the need for adequate lightning protection measures for all tall structures.
The thunderstorm days in UAE are about 10 per year as mentioned in BS 6651, page 14, figure 3. With tall structures coming up in Dubai, the probability of a lightning strike is much higher. A 100m-tall building (30 floors) is five times more at risk in comparison to a 50m-tall building (15 floors).
This risk factor goes up, as the height of the building goes up. This probability of lightning strike is calculated based on utility, type of construction, consequence, isolation and location of the structure. It thus seems mandatory to have lightning protection which is pro-active, intelligent, synchronisable according to lightning polarity and remotely monitored lightning protection systems for tall structures.
Brand new projects or re-construction of older structures must encompass latest technology and international best practices in all aspects of their design and performance. Electrical safety is no exception. Optimal electrical safety standards demand dependable and maintenance-free systems.
Periodically maintainable system needs complete abolition, as it is impossible to have human resources employed for this purpose; each time maintenance is overlooked, the building becomes incompliant with all known safety standards. Some buildings continue to rely on high maintenance options as they are deemed cheaper, when technologically advanced options which are far more durable and effective are readily available.
Design parameters of projects need to be followed uncompromisingly as existing science is capable of providing adequate solutions for known problems.
Dubai's fast-paced growth is being fuelled by a rapid influx of residents and this has a directly proportional effect on the nation's infrastructure. Poor safety and maintenance by contractors can lead to unwanted repercussions. However, it is my firm belief that the regulatory situation in the UAE will improve. The consultants and advisers to the government have been very receptive towards addressing this issue.
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