How can we make our buildings safe?
Dr AFM Saiful Amin, Professor of Civil Engineering, Bangladesh University of Engineering and Technology (BUET), talks to Nahela Nowshin of The Daily Star about the causes and ramifications of our failure to comply with the Bangladesh National Building Code, and more.
What are some of the most common ways in which the Bangladesh National Building Code (BNBC) is violated?
Defiance of the BNBC stems from the ways that it can provide immediate benefit to owners and often the users and the developers of buildings. For example, rules are violated to achieve maximum use of space when land itself is costly. To maximise land use, a building’s ground coverage (footprint) is increased, allowing less horizontal clearance between the adjacent buildings or road perimeter. Buildings are constructed taller than permitted by the code to obtain extra floor space from the same piece of land. These exercises impair not only the owner’s building, but adjacent buildings too become less serviceable because of limited access to daylight and there are privacy issues as well. Future widening of adjacent roads is restricted also. These buildings become more vulnerable to extreme events like earthquakes and fire hazards. To increase the useable floor space, smaller column sizes and narrower emergency escapes are often preferred that reduce structural and operational safety in extreme situations.
Provisions in the building code aiming to eliminate fire and electrical hazards are violated to save construction and operational costs. Electrical connections are rarely inspected; gadgets installed for fire detection, suppression and fighting often remain unserviceable or used beyond their expiry dates; fire drills occur in very rare cases even in high-rises. Use of low-quality materials coupled with low construction quality compromise much of the structural, electrical and fire safety. The requirements in the code for different occupancy types, number of occupants and building heights are not the same. Often a building designed and constructed for residential purposes is used for commercial or industrial purposes without addressing the additional demands that the code requires for such usage. Structural integrity as well as fire and electrical safety requirements are often compromised by changes in usage type without appropriate and authorised alteration to the original construction.
What are some safety-related measures mentioned in the BNBC, including fire safety?
The BNBC stipulates different precautionary requirements for fire protection depending on usage type, occupants and construction type. A building may not only need to have its own working system to detect and suppress a fire, but also fight a fire via fire extinguishers, sprinklers and even fire hoses directly connected to the fire pump and reserve water until firefighters reach the scene. Fire doors at the fire exits and fire chutes will keep the fire escapes free from smoke so that people can evacuate safely and promptly when everyone gets to know about a fire incident through command centre announcements or spontaneous activation of fire alarms.
However, operational efficiency in dealing with these hazards in extreme situations depends on the preparedness of the occupants in a building and their fire safety plan. In the regular fire drills stipulated in the BNBC, occupants must not only learn about the uses and necessities of these measures but drills must also familiarise them with such hazards and their means of escape at their premises. They are supposed to learn about the system and the operational capacities of all equipment, devices and means tested onsite during the drill. They must know to use the stairs and that elevators mustn’t be used.
In our society, because of public safety issues, most of the collapsible gates in the lone stairs of a building are found locked. This means that occupants may not have the chance to escape a building in the event of a fire if they don’t have access to the keys. The basic issues of civil defence in regard to safety during fire, earthquake and electrical hazards should be a part of general primary education.
There are numerous buildings in the city of Dhaka, like FR Tower, which have built extra floors without permission from Rajuk. Demolition of these extra floors does not seem practical. How can this issue be addressed?
The Building Construction Act for the city of Dhaka has seen several revisions since 1952. Dhaka Imarat Nirman Bidhimala 2008 had been introduced after enacting the BNBC which was drafted in 1993 and endorsed as law in 2006. Addition, alteration or modification of an existing building must meet the requirements of the prevailing code and also conform to those required for a new building under the applicable code. Evaluating the compliance of an existing building may require referring to its construction history. Bangladesh’s building code has no provision to declare an unsafe and noncompliant building a safe and compliant one or permit its usage without it undergoing certain modifications or alterations such that the noncompliant building meets the code requirements, viz. ground coverage, height, structural integrity, fire, plumbing and electrical safety for a particular usage. Conversion of a building to low-demand usage might also be an option in some cases. Owners and users are not usually interested in these modifications and alterations for the fear of costs and interruptions in rent or business unless they are essentially forced to do so.
Modifications to meet the ground coverage, height and fire escape requirements are the most challenging tasks for the engineer and the architect, while structural integrity can be restored through appropriate strengthening methods. Equipment like fire extinguishers, sprinklers and fire hydrants can be skillfully designed and quickly installed, but will require regular inspections to ensure they remain active and operational when a fire incident takes place. With the depletion of groundwater, water scarcity in Dhaka and disappearing lakes, it is becoming a daunting task to fight a massive fire unless it is extinguished at the source with intelligent detection technology, such as smoke and fire detectors coupled with water sprinklers. Ensuring electrical safety and safe storage of flammable and toxic substances will drastically decrease fire incidents and related injuries.
What are the government agencies responsible for overseeing the BNBC and involved in the process from design to construction of a building?
At this moment, no exclusive regulatory authority exists to check the compliance of buildings per the BNBC or other government regulations. Rajuk has been given responsibility for Dhaka city and Chittagong Development Authority. Local pouroshovas and other local bodies look after matters in the rest of the country. However, while all these bodies have several other responsibilities and services to deliver, they often lack enough skilled manpower to inspect the huge number of buildings in their respective jurisdictions to enforce compliance. Misinterpretation and manipulation of the code are common due to ignorance or other vested interests, besides malpractice (ignoring a noncompliant building). In such situations, many countries around the world depend on regulatory authorities who train to prepare certified inspectors to conduct inspections, issue and regularly validate occupancy certificates, and submit regular reports to the authorities in case of violations for appropriate action to be taken. The inspectors have adequate knowledge of building laws and consequences, architecture, surveying, quality control and the required specifications, and are trained well enough to read the drawings produced by qualified designers. The cost of such inspections can be covered by city taxes. To make the system accountable and workable, certified building inspectors can work under the direct supervision of a few private licenced corporate bodies which will be directly accountable to the regulatory authority of the government.
This regulatory authority will then be substantially able to reduce its workload for regular decisions, delegate authority to capable hands, hold them accountable for their actions, and concentrate only on more critical issues and large projects. This can ensure quality service for city dwellers, and reduce harm from deliberate malpractice and corruption through adequate enforcement of the law. All coexisting laws, acts, regulations and guidelines need to be compared and streamlined to make all these actions more efficient and convergent. Professional bodies for engineers, planners and architects, viz. Institution of Engineers, Bangladesh, Institute of Architects, Bangladesh and Bangladesh Institute of Planners, need to be strengthened so that qualified and capable professionals can be made directly accountable for their designs. Design clauses in the building codes can be updated by these professional bodies in quick intervals as is practised around the world.
Source: The Daily Star.