1. Research background and method

The form carpenter’s labor intensity assessment in 2018 showed that calory consumption of the workers was highest in the order of the main floor of the apartment, the house, and the basement of the apartment. For the main floor of the apartment work, which is still operated as a contract, the union members’ perception of much higher labor intensity than other sites was confirmed. The reduction of working hours, eradication of illegal subcontracting, and employment stabilization at construction sites that the labor unions have been struggling with have not been accomplished in the worksite on the main floor of the apartment. As a result, the labor intensity at the apartment main floor site continued to be high.

This not only threatens health of workers working on the main floor but also prevents union members from entering the main floor work. Therefore, the main-floor labor intensity evaluation project was conducted with the aim of identifying the labor intensity and work content of the current apartment main floor work in detail and then creating basic data for further plans, such as organizing main-floor workers.

2. Survey Results

First of all, the working hours of workers engaged in the main-floor Aluminum formwork were 9.65 hours on average, which was a longer compared to other worker groups. The average value of the Borg scale index, which reflects a subjective labor intensity, was 14.36. The pressure to shorten the construction period, which demands completing one floor per one day, and the bonus/subcontracting system seemed to have an effect. As the working hours are long and they have to keep working busy, the relative labor intensity was also high. Survey respondents reported that labor intensity should be reduced by 30% from the current level.

The risk factors of the main floor aluminum formwork are largely classified into ergonomic, physical, and chemical factors. In case of handling heavy objects among ergonomic factors, 78.6% of aluminum formworkers on the main floor reported that they were exposed to risk of ‘handling heavy objects’ for at least 1/4 of their working hours. Among the difficulties associated with aluminum formwork, the problem of handling heavy objects is in line with the high prevalence of musculoskeletal symptoms and the experience of injury.

When examining the self-reported musculoskeletal symptoms by body part according to the NIOSH criteria, 52.7% of the participants reported symptoms of criterion 1. Due to the characteristics of the construction industry and the high labor intensity of aluminum formwork, the symptom complaint rate (on any part) was more than half. Considering that the average age is low and the work experience is short, it can be interpreted as proof that the musculoskeletal symptoms occur quickly within a short period of time, and thus, the labor intensity is relatively high. Looking at the prevalence of musculoskeletal symptoms by body part, the low back showed the highest prevalence of musculoskeletal symptoms (40.9%). It can be said that the risk of Badachigi (carrying aluminum forms between floors through ceiling), which is the characteristic of aluminum formwork, has a significant effect on the occurrence of musculoskeletal diseases. In order to prevent the risk of handling heavy objects, it is necessary to discuss alternatives such as ensuring enough break time, introducing a heavy lifting device, and reducing material weight.

In the case of physical hazards, the response that they are exposed to high temperatures in summer was about 10 times higher than that of the total working population in Korea from the Korean Working Condition Survey. In hot or cold seasons, the safety and health management recommendations by the Ministry of Employment and Labor should be observed. Regarding noise exposure, in addition that workers responded they were exposed to noise throughout their working hours, the measurement of the working environment confirmed that the average noise level was 93.9dB which exceeded the exposure standard. There is a need to provide safety equipment to prevent noise, such as earplugs.

From the results of the survey, it can be seen that migrant workers, especially from countries in which workers’ status are poorer, have relatively longer working hours, higher labor intensity, and higher musculoskeletal symptoms or injury experiences although they are young. In other words, the working environment and working conditions of migrant workers have an effect on increasing the labor intensity of the main floor workers. Further studies, such as comparison studies between migrant workers, are needed.

3. Interview results

A total of 20 workers including members of the Korean Federation Construction Industry Trade Union and migrant workers participated in the interview. By evaluating the labor intensity of the main floor from the perspective of workers through interview surveys, we investigated the perception of workers on the labor intensity and work environment, the cause of the current labor intensity, and the alternatives that the union should prepare.

It was found that aluminum formworkers at the main floor construction site of apartments shared the problems of high labor intensity and job stress felt by construction workers in general, from such as social undervaluation of construction labor, irregular work schedules, and unstable income.

In addition, they clearly recognized the high labor intensity of the main floor aluminum formwork. They themselves have the perception that aluminum formwork may not difficult and complicated, but demanding, because of handling of heavyweights represented by so-called Badachigi, which carries 10~30kg of foam and materials between floors through ceiling, a work process that does not have enough time throughout the work because they have to complete one floor a day, and the perception that it is a messier job than a conventional carpenter because the oil gets into the hands due to the use of a foam oil, the condition in which they continue to suffer from metallic noise, and working for a long time in the scorching sun, 

In the background of this problematic work process, there is the pressure of shortening the construction period associated with the contracting system that dominates the construction work on the main floor, and the problem of undocumented migrant construction workers that have economic and social motives to endure this. In this situation, the problem of the right to health of aluminum formworkers on the main floor has not been paid attention with the perception that the ‘they are less injured than others’ and ‘they can make a lot of money even if their work is dirty and difficult.’ This may be even more so because the majority of the workers are migrant workers in the blind spot.

During the interviews, we were able to reconfirm the findings from the survey, and at the same time reveal the perceptions of workers and the cause of labor intensity. However, the union’s alternative to alleviating labor intensity has not been clearly conceived. It is necessary to have open and full-scale discussion within the union to shape up the demands for an appropriate construction period and an appropriate wage. In addition to technical alternatives such as adjusting the aluminum form standard or introducing a lifting machine, it will be of paramount importance to adjust the working process itself on the main floor. This is to increase the construction period per floor or to increase the number of workers, which is closely related to the profits of the construction company. Therefore, more difficult tasks such as contract relations and undocumented migrant workers are faced. We think that this is the time when fierce thoughts and open discussions are needed.

4. Results of field research

Field surveys on the main floor of the apartment construction were conducted in Seongnam, Gyeonggi-do on May 25-26, Busan on June 20 and 22, and Busan on August 18-19. As a result of on-site evaluation, it was confirmed that most of the daily work can be defined as musculoskeletal burden tasks of almost all body parts. The 11 types of musculoskeletal burden tasks specified by the Ministry of Employment and Labor are for formal tasks, so they do not reflect the characteristics of the construction industry well, in which the position and movement constantly change during the process. Nevertheless, the aluminum formwork on the main floor fell under the burden of various musculoskeletal tasks.

Among the various musculoskeletal burden tasks, the most problematic task was heavy lifting. Heavy lifting is not only a risk factor for musculoskeletal disorders, but is also a representative risk factor increasing labor intensity that affects the cardiovascular system. Originally introduced for lighter weight, as the size of aluminum form increased, the material became excessively heavy. As with mid-beam assembly work, if you assemble several materials to create a structure to shorten the working time, it gets much heavier. It is necessary to prepare a plan to solve the problem of excessive heavy lifting such as reducing material weight, reducing the size of the aluminum form, and introducing a lifting machine.

At the same time, very simple safety rules were ignored in the field. Carrying too heavy materials, heavy lifting that occurs because two people could not share, and safety rules that are skipped for quick and easy work not only increase the intensity of labor but also increase the risk of accidents. In addition, the main floor aluminum formwork is exposed to various risk factors in addition to musculoskeletal risk. Typical examples include noise, dust, chemicals, direct sunlight, and high temperatures. These poor physical environments also play a role in increasing labor intensity. In addition, the labor intensity of main floor workers was very high due to shorter breaks and longer working hours than in the conventional section.

With these various aspects, the labor intensity of the main floor aluminum formwork is very high. With the risk of tripping, falling, etc., they are carrying out musculoskeletal burden tasks of almost all body parts. The working environment is poor, but the working speed is fast and the working hours are long.

5. Results of work environment measurement

The level of exposure to dust and noise of aluminum formwork was evaluated by measuring the working environment four times. The concentrations of total dust and respiratory dust were low, and crystalline silica, a carcinogen, was detected only in two of the total 18 samples (excluding two local samples), which was about 1/10 of the exposure limit of the Ministry of Employment and Labor. On the other hand, noise exceeded the exposure limit (90 dB) except for one of the 22 samples. The average was 93.9 dB, and the maximum was 96.6 dB.

The concentration of dust was relatively higher in August than in June, and crystalline silica (quartz) was also detected in only two samples in August. The reason for this is probably that the investigation was conducted only on the ground floor where the upper part (ceiling) was open, so it was directly affected by particulate matter in the atmosphere. Therefore, in addition to measures against heat and cold caused by outdoor work, it is also necessary to take measures to prevent exposure to particulate matter.

The level of noise exposure of the aluminum formworkers on the main floor was serious enough to exceed the exposure limit. However, because of the nature of team-based work, earplugs were hardly worn to facilitate communication during work. Moreover, according to the findings in the interview, workers said that wearing earplugs when disassembling aluminum form makes it difficult to perceive the danger. There were also sites where earplugs were not properly supplied. Earplugs should be provided individually, but it is necessary to carefully investigate whether it is difficult to wear them due to the working conditions. As another alternative, there might be the introduction of low-noise aluminum forms and low-noise tools. As for the noise problem, urgent improvement is necessary.

6. Results of biomarker measurement

Over a total of 6 days, a total of 29 workers on the main floor were measured for their biomarkers wearing an actigraph and a heart rate meter during working hours. 27 of them were measured the amount of physical activity and 10 people were measured the heart rate during the work.

As a result of measuring physical activity, the average calory consumption per individual during work hours was 134 kcal/hour. They were using 5.85 times more energy than white-collar workers and 2.71 times more than workers in the automobile manufacturing industry measured by the same methods. It also was 1.27 times more than the calorie consumption of the apartment basement team measured in 2018. Extreme labor intensity is a risk factor for cerebral and cardiovascular disease, and it is necessary to lower it to an appropriate level.

The maximum optimal working time and overwork index were calculated using the observed heart rate. Of a total of 10 participants, 7 were found to be overworking. The maximum appropriate working hours were calculated to be 7.35 hours on average, but a significant number of migrant workers were working for more than 9 hours. For some workers, there have also been results that it is desirable to reduce work to less than half of the current workload. The average overwork index, which means the ratio of the actual working hours to the maximum appropriate working hours, was 1.5, which means that working hours should be reduced by 33% of the current working hours. For one worker, who has an exceptionally large overwork index, we found that the workload should reduce to less than one-third of the current workload, and for the other two workers to less than half of the current workload.

Strenuous efforts to reduce labor intensity are also needed in that the maximum appropriate working hours should be interpreted not as a standard that you should work for, but that you should not work more than that. In addition, as this maximum appropriate working hour assumes standard daytime work and five days a week, the fact that construction workers of the main floor work on Saturdays must be considered. Furthermore, since the biomarker measurement in this study was conducted on healthy workers of various ages, the appropriate working hours should be lower for the more elderly Korean workers. It is an urgent task to reduce the intensity of labor at the construction site of the main floor of an apartment. 

7. Conclusion and Suggestions

First, there is an urgent need to prevent musculoskeletal disorders and improve the working environment. Aluminum formworkers with high labor intensity should properly have the right to receive treatment through the workers’ compensation system. In addition to proper compensation, preventive activities should be carried out to reduce the musculoskeletal burden in the main floor aluminum formwork.

It is the most urgent task to reduce handling of heavy materials to improve the environment of a main floor construction site. Weight reduction such as reducing the material size or weight per unit of material so that only the proper weight could be handled can be implemented, and a technical method of introducing a lifting machine in the ‘Badachigi’ work is also possible. The operational policy is also important to ensure sufficient breaks between works.

In the medium term, it is necessary to heighten awareness of the workers’ right to health among the aluminum formworkers. Undocumented migrant workers may even more so. There is a need for labor unions to reinforce labor safety and health activities to discover health and safety problems at construction sites, and to heighten awareness of problems through them. First, it is needed to reveal specific problems that increase the intensity of labor in the field, and next, we need to ask for solutions to them and improve the workplace.

In the long term, it is necessary to achieve an appropriate labor intensity in the main floor aluminum formwork and to set an appropriate construction period for this. Lowering the labor intensity of the aluminum formwork on the main floor is related to the entire construction site of the apartment and the pressure of the construction period of completing one floor a day. The general practice of ‘one-day’ work on the main floor of the apartment acts as a pressure to increase the intensity of labor and increase the speed of work.

Therefore, the demand for an appropriate construction period is to protect the health of the main floor aluminum form workers by lowering the labor intensity and making the workplace safe. However, in the long run, it is important to change the labor relations or industrial structure of multi-level subcontract that makes this difficult.

It can be considered to secure an additional one or two people for each job in order to reduce the current labor intensity right away since changing of labor relations or industrial structure are long-term tasks. In addition, an active response to construction companies must be accompanied. In the long term, strategies and tactics must be devised to ensure that the main floor aluminum formwork can be carried out with an appropriate labor intensity and over an appropriate construction period. In addition, various experiments should be attempted actively so that this can be achieved in the actual workplaces.