Construction Site Safety – Human Reliability and Training

Falls, electrocution, crush injuries, chemicals; the construction site can be a dangerous place. In the second of a two-part article, SCT’s Mario Pierobon reports on human reliability and training.

If one considers the economic output and the number of people employed, construction is among the largest industries in most of the world’s countries. The construction sector is considered a hazardous one because the nature of the working environment comes with risks of accidents and incidents for employees at constructions sites. Human performance and limitations play a significant part in the risk profile of construction operations; in this second part of a two-part story on the subject we shall review work physiology, the individual characteristics of the workers, and human reliability in relation to human performance and its limitations.

Work Physiology

Work physiology is an important aspect to consider in raising awareness on human performance and its limitations in the construction business, as it helps to evaluate and prevent work strain. “It involves the capacity for physical labour that was found to be different from person to another. Examples of work physiology are the level of physical fitness, nutritional status, age, gender, and health,” say Kamal et al. [i].

As far as age is concerned, older workers perform task in a slower way with proper skills, while younger workers perform the tasks at a faster pace, observe Kamal et al. “Therefore, physical screening is important to determine the capability in every worker to fit them with the task,” they say.

One tactic for handling work physiology is work-rest scheduling, i.e., an arrangement of working hours that is different from the usual one so to provide more rest hours for the workers to recharge their energy, note Kamal et al. “The duration of bouts and rest pauses should be regulated to account for the worker’s age,” they say. “Improper work-rest scheduling can contribute to accidents which may influence human performance due to lack of task error analysis.”

Stress levels also affect human performance in construction sites. “Stress includes physical, psychological, financial, excessive workload, time pressure or physical stress (heat, dust, noise, high temperatures, illumination, etc.) which are present in the work environment,” say Samarth and Prabhat [ii]. “Evaluation of this shaping parameter is of paramount importance in the safe construction of infrastructure projects.”

Characteristics of Workers

As part of addressing the individual characteristics of workers, K. H. E. Kroemer, H. J. Kroemer, and K. Elbert  [iii] point out that individual differences in skill, motivation, body weight, age, gender, involvement of muscle groups while performing the task related to the technique of performing the task), general health, and degree of physical training, can all affect energy expenditure.

Consideration to human factors’ aspects can lead to modifying working procedures with focus human being psychological and physical capabilities and limitations, explain Kamal et al. “The three basic ways for determining worker’s characteristics and performance are personnel orientation, selection, and training. New workers need to be trained to perform their task safely, to recognize, understand, and avoid potential hazards to themselves and others.”

Indeed, the overall competence is a significant characteristic, and it is based on knowledge, skills, abilities, training and experience of the construction personnel involved in the tasks, explain Samarth and Prabhat. “The number of working years and the nature of tasks performed over years and the workmanship determine his level of competence and reliability. The individuals performing the task are physically and mentally fit to perform the task at the required time. The elements that may affect fitness includes fatigue, personal problems, distractions, etc.”

Training is fundamental to develop the individual skills that need to be developed and it is for the managers to also undergo safety training because they are leaders on site. They also have the role to analyse data as independent consultants through interview with workers and during informal discussions with supervisors, and identify differences between job requirements and individual skills, according to Kamal et al.

It is the role of the safety manager to ensure that new and experienced workers have received the training to do their task in a safe way, point out Kamal et al. “In addition, contractors (temporary workers, subcontractor workers, visitors, and others) may need specific training to recognise the hazards at construction sites.”

Human Reliability

One last important aspect to consider in relation to human performance and limitations in construction sites is human reliability. “The human reliability in construction activities plays a key role in safe and timely execution of the project. Construction is a skill and attitude-based activity with good awareness and knowledge on hazards” say Samarth and Prabhat.

Ensuring human reliability is key due to the presence and contribution of humans to the constructions as an unpredictable and complex system. “Construction is widely known as a skill and ability (physical & mental) based activity with sound awareness and knowledge on hazards,” say Samarth and Prabhat. “In construction many jobs are mostly carried out manually with less automation by majority of unskilled/semi-skilled and illiterate labour in a dynamic work environment, so this has a high probability of human error. The dynamic uncertainties, transitions and relationships at workplace necessitates a thorough study to evaluate the human reliability while performing construction activities and impact on safety culture.”

“To enable safe performance, the efforts have to be aligned and integrated into the flow of resources, management processes to identify constraints and barriers to effectively plan and manage risk, as well as create a climate of trust and cooperation fostering empowerment and engagement resulting in optimal safe performance,” conclude Samarth and Prabhat.

References 
[i] Kamal et al.
[ii] Samarth & Prabhat
[iii] K. H. E. Kroemer, H. J. Kroemer and Kroemer Elbert, Ergonomics: How to Design Ease and Efficienc”, 2nd edition, Englewood Cliffs, NJ: Prentice Hall, 2001