CHAPTER 5. DISCUSSION, CONCLUSION AND
5.2 DISCUSSION
This study is the first in Tanzania to investigate the relationship between the regulatory framework (using the time period of introduction of the instrument as a proxy marker), and trends in the frequency of work-related fatalities and severe injuries among
construction workers in the country. The study has shown that most of the new governing bodies, as well as the introduction of new policies and legislations in construction sector, have been effective in terms of a reduction of reported accidents.
This study has also been able to identify some indicators, frequency, and trends on fatalities and work-related injuries for the duration of thirty years.
5.2.1 DESCRIPTIVE ANALYSIS
The analysis of construction workers indicates that labourers were the most at risk of severe injury for occupational injuries of all categories in both the construction (49.3%)
and non-construction sectors (70.9%). The age group 26 – 30 years had the highest reported cases, ,followed by the age group 31 – 35 years which may be due to those age groups being the most active in the labour force in Tanzania (22). This highlights the need for improved instruction and safety measures for these ages on site, and every effort needs to be made to reduce the number of serious injuries at this stage of their lives.
Despite the fact that many construction workers were manual labourers, education appeared to play a role in reducing the risk of injury, with those having at least a secondary education or higher level of schooling being less likely to suffer from serious injuries than those with lower levels. This indicates the need for appropriate
supervision at all times, given that this situation is unlikely to change, and highlights the need for communication within the industry regarding risk reduction strategies.
This study has shown that 10.6% of all reported case happened in the construction sector. This is similar to the results of a study conducted in Dar-es-Salaam in 1990 which shown that 10% of accidents was contributed by construction sector (2). The results indicated that the common causes of injuries or fatalities in the construction industry were: hit by moving or flying object (26.7%); slipped, tripped or fell on the same level (12.7%); hit by moving vehicle (11.9%) and moving machinery or material being machined (11.1%). This is similar to studies elsewhere which had shown that the common causes of fatal injuries in the construction industry include falling (ranges from 7% to 52.7%), motor vehicle accidents (ranges from 8.2% to 23.4%), and electrocutions (ranges from 7% to 9.6%) (48), (49), (50), (51), (52). This highlights the lack of
adequate safety measure with regard to manual handling, the movement of equipment, machinery, objects or vehicles on construction sites. While workers in the industry are a number of risk factors, a concerted effort needs to be made to identify those risk factors and safety measures should be improved.
5.2.2 BIVARIATE AND MULTIVARIATE ANALYSIS
The years used in the analysis were those in which the instruments, policies or agencies were brought into operation, and were taken as a proxy marker for that instrument,
policy or agency. Most instrument, policy or agency were established to regulated OHS in the construction industry, except for the Factories Ordinance, Mining (safe working and occupational health) regulations, OSHA and OHS Act 2003. Cases reported during these time periods were considered and are as illustrate.
Between 1986 and 2009,compared to baseline period (1980 – 1981), the occurrence of accident in the construction sector was reduced by approximately half compared to in the non-construction sectors. This suggests that the newly established regulatory bodies and legislation introduced during this period had a substantial impact in the protection of workers. The logistic regression models indicated that the introduction of new regulatory bodies and legislation decreased the risk of fatalities and work related injuries frequency in the construction industry between 1986 and 2009, except for the years between 1982 and 1985 (OR 1.2; 95% CI 1.0 to 1.3). This suggests that
establishment of the National Construction Council in 1997 did not contribute to the reduction of fatalities and work related injuries frequency in the construction industry.
However, the decrease of risk of reported cases in the construction industry between 2004 and 2009 (OR 0.32; 95% CI (0.3 to 0.4)) compared to baseline duration indicates that the enactment of the of the OHS Act 2003 and the National Construction Policy in combination with the previously established regulatory bodies and legislation had an impact in reduction the accidents.
The adjusted risk of getting injured (according to reported cases of fatal and non-fatal) n the construction sector increased from 1982 and 1985 compared to baseline period (OR 1.2; 95% CI 1.0 – 1.3). This may have two explanations. One is that the Factories Ordinance CAP 297 and Institution of Engineer Tanzania were inadequate, which resulted in an increase of the number of incidents of injuries or fatalities, and the other that there was no specific legislation for the construction sector, which led to increase of accidents. However, it was not possible to obtain information to conclude on any of the above explanations.
Generally, this study has shown that there is evidence to support the hypothesis that the establishment of regulatory frameworks and legislation in the construction sector has
reduced non-fatal and fatal injuries, this being similar to studies conducted elsewhere.
The studies that were conducted in US in 2001and 2003 to evaluate regulatory intervention on vertical fall found that establishment of regulations to be effective in preventing non-fatal and fatal injuries in the construction industry (45), (46). The decline in cases of accidents seen in the latter studies was about twice the number compared to the period before establishment of intervention. Another study was
conducted in 2002 to evaluate the establishment of trench and excavation standards, and showed an effectiveness in reducing the risk of fatal injuries due to falling into trenches (2-times decline) following the implementation of the intervention (47). We could not compare the results of this study among developing countries due to lack of published studies in the latter.
The analysis by Cochrane to assess the effects of interventions for preventing injuries among workers at construction sites that included the above studies was done in 2012.
The analysis found that regulatory interventions did not show either an initial or
sustained effect on fatal or nonfatal injuries (Effect Size 0.69) (28). The reason for such a result was mentioned to be low quality overall study methodology.