Safety Challenges in Construction

Introduction

The construction industry in India is the second biggest employer after agriculture and one estimate puts the numbers employed in this sector around 50 million presently and slated to grow to 90 million in the next 5 years. Most of the people working in the construction sector are unskilled with little or no education/ training and the job is of a casual nature. Agriculture is mostly working at grade whereas construction involves working at heights or depths as the height and complexity of structures become more challenging as the years roll on. The industry is fraught with inherent hazards and the attendant risks that go with it added to the workforce not fully aware of the hazards and mitigating steps needed to prevent injury at the place of work.

The biggest challenge in the construction industry is to ensure that human lives are not affected by the various activities and tasks that form part of construction. Being a labour intensive industry it is imperative that a large number of people must be deployed on the work site to deliver the project. The tasks that a person employed at site undertakes puts his health at risk and in some cases, life is also at risk when working in hazardous and high-risk areas like working at heights, deep excavations, confined spaces and even underwater. The term accident is associated with construction related as much as with traffic accidents since the reach of this business sector is far and wide.

Legal framework

The Government of India acknowledging that construction is also an industry by itself and the construction workers are unorganized and are exposed to occupational hazards with very little legal protection, passed the Building and Other Construction Workers Act in 1992 and amended it in 1996. The States were asked to prepare their own rules to be enforced by an appropriate authority appointed for their enforcement. Some States brought it under the Inspectorate of Factories and others under the Labour Officer. The Government of India is currently bringing together the Factories Act 1948, Building and Other Construction Workers Act 1996 and other relevant Acts (dealing with Mines, Dock Workers are two other important Acts) dealing with occupational health and safety at the workplace and is proposed to be called the Occupational Safety and Health Act spanning across all sectors where human effort is exposed to hazards. This would ensure that sectors that were not included earlier would be included under the new act and include both big and small businesses, contractors, plants, etc.

Overview of Construction Labour

Traditionally the labour for the construction industry is from a rural background and are exposed only to agricultural work. During the break from the work on their land they turn to taking up work at the construction sites. They arrive at the construction sites with no prior skill in working as a tradesman in the carpentry, steel fixing, bricklaying, tile fixing, and painting, etc. trades. Therefore, it results in a steady turnover in the workforce in the construction industry with workmen available only for short periods of three to four months maximum in a year on site for work, resulting in construction companies having to constantly equip the workforce with the necessary skills to carry out work.

Construction sites today

Today in India the construction industry is at par with global companies in the deployment of latest machinery and equipment. Gone are the days when only manual labour was involved in excavation of canals, lifting of material in buckets to higher elevations – all by forming a human chain.

Indian cities are growing rapidly with more and more people moving into them for work and demand for office space and residential accommodation keeps growing. Cities are growing vertically due to space constraints in preferred areas of cities; hence construction of taller buildings/ towers is the most favored by all stakeholders. Vertical construction needs methods of shifting men and material to higher elevations and they must work at heights, a couple of hundred meters and more, as the buildings rise from just single storied ones to multi-storied cloud enveloped skyscrapers. The construction industry records the maximum number of accidents with serious injuries and fatalities due to fall from heights globally and India is not behind in this area.

Up-scaling of site activities

Earth moving equipment have enabled speed and safety in excavations; large excavations can now be done with minimal human effort and exposure to manual and ergonomic hazards of the worker is eliminated. The men operating the earth moving and rock breaking equipment are trained to operate them in a safe manner with the training being provided by the manufacturers themselves, a mix of classroom teaching and at site demonstration and practice on the equipment.

As the size of the building/ structure increased the demand for concrete increased multiple times and traditional mixers were not sufficient to deliver the quantities. Therefore concrete batching plants with large capacities of production per hour were installed. The concrete is transported in transit mixers to the location where a pump is provided either static or truck mounted, and the concrete pumped to the final location through pipes. The construction of taller buildings or high-rise buildings requires powerful pumps and suitable piping for delivery of the concrete.

Working on taller structures

Taller structures require securing leading edges to prevent fall of men and arrangements to prevent fall of material from higher elevations during construction. Shifting of material is now done mechanically with cranes and hoists for shifting material unlike earlier when it was all manual, and the height was a couple of stories only,. Workers are transported vertically using passenger lifts with large carrying capacity (20 to 30 persons capacity for the car).

Tower cranes with very long booms providing a wider reach are also a common sight and communication between the operator and the signalman is by walkie talkie and CCTV for better communication as the crane operator would not have visibility of the signalman to ensure safe operations of the crane.

Some sites have multiple tower cranes (15 and more) since the size of the plot is huge and work is being carried out simultaneously and multiple cranes are required for coverage of the entire plot. In such a situation anti-collision device are fixed since there is a likelihood of overlap of the cranes area of coverage. The erection and dismantling of these cranes are a high-risk activity and requires special training and skills to carry out the task.

Some sites have multiple tower cranes (15 and more) since the size of the plot is huge and work is being carried out simultaneously and multiple cranes are required for coverage of the entire plot. In such a situation anti-collision device are fixed since there is a likelihood of overlap of the cranes area of coverage. The erection and dismantling of these cranes are a high-risk activity and requires special training and skills to carry out the task.

Introduction of Tunnel Boring Machines

Construction of road and rail networks often requires the route to be through hilly and rock terrain or underground in congested urban areas where the ground space is limited. Tunnels provide the answer and also reduce the distance between two points. In the past the method adopted was to use blasting with explosives which was time consuming. The introduction of Tunnel Boring Machines using state of the art technology has increased the speed of construction of the tunnel resulting in quick commissioning of facility.

Safety in construction projects starts with the planning phase when all the use and space requirements come together, the plans are drawn up and the design engineer carries out the structural design in accordance with the codes. Compliance with the codes is normally enough to ensure the safety of the design, however the designer must consider the various parameters like wind, earth quake zoning, live load, of late fire load, blast loading plus any other condition that would have an impact on the performance of the structures in. The next is the performing phase and the actual works commence with a planning of the various sequences and resources in a phased manner and ensuring the workers are not exposed to hazards and the accompanying risks. Systematic training programs are done, and regular inspections are also carried out. Depending on the type/ size of the project various parameters are developed to measure and monitor the project.

Digital Era

In the present digital era and use of new technology for capturing data, remote control accessing and monitoring of construction sides has improved the overall delivery of the project. Equipment are more reliable with increased micro processor controls and the presence of cameras at multiple locations aid in monitoring a construction site 24/7 on large screens. The use of planning tools to predict what could possibly go wrong in a given scenario has led to reduction of accidents on construction sites.

Consultant engineers are fully responsible for the design and supervision of safety and have a legal duty to ensure compliance with the codes and statutory regulations.

( Published in the Consulting Engineers Association of India Journal of September 2019)

Josy John - Corporate Safety Head at TATA Consulting Engineers