Associated factors of electrical injuries and knowledge on their prevention and first aid management among Ceylon Electricity Board ( CEB ) field level technical workers in Colombo municipal area .

Results The sample consisted of only males, with a mean age of 37.19 years (SD=11.08). Self-reported injury incidence among the workers was 6% per year and no significant association was seen between injury incidence and any of the sociodemographic or work-related characteristics. Majority had a good knowledge on prevention (75.8%) and first aid management (81.7%). Having a total number of 1 to 3 training sessions on prevention during the time of occupation showed a significant association with knowledge on prevention (p=0.006). Occupational grade showed a significant association with knowledge on first aid management (p=0.013).


Background
Occupational injuries are defined as any personal injury, disease or death resulting from an occupational accident [1].Approximately 2.2 million people die, 270 million suffer serious non-fatal injuries and 160 million fall ill every year from occupational injuries all around the world.In Sri Lanka, about 4,000 accidents are being reported yearly and the number of working days lost is estimated to be around 600,000 workdays every year [2].Electrical injuries are one type of such injuries. .Among 16000 Ceylon Electricity Board (CEB) workers, about 56.3% are technical workers who are skilled, semi-skilled or non-skilled.They are at constant risk of being exposed to electrical injuries, which are classified according to the number of days which a worker has been absent following an injury.In a minor injury, a worker reports to duty within 3 days and in a reportable injury it takes more than 3 days [3].Seven fatal injuries (13.2%), 36 reportable injuries (67.9%) and 10 minor injuries (18.9%) were among 53 such reported injuries in CEB during the year of 2014 [4].
In a study done in 2012, the prevalence of occupational injuries in CEB, Western Province North was 7.6 per 100 workers per 6 months and the annual estimated prevalence of such injuries was 15.2 per 100 workers.The pattern of injuries was different with 78.3 % being due to minor injuries while 21.7% were reportable injuries [5].
Among factors associated with occupational injuries, the socioeconomic factors may be considered the most important.They exert a considerable influence on the injury frequency, especially if considered over a long period [6].According to the study in 2012, occupational injuries were more likely to be in young (<39 years), married, unskilled, less experienced, less trained workers with frequent use of unsafe equipment [5].
International literature on the same topic suggest that the electrical injury incidents are associated with work inappropriately or inadvertently performed on energized equipment, failure to recognize all electrical sources, insufficient training and failure to use appropriate Personal Protective Equipment (PPE) [7].
In CEB workers at present, aspects practiced for preventing electrical injuries are proper use of PPE, maintaining safety distance from high voltage live conductors, proper supply interruption and earthing of lines at work and applying special safety methods [8].
Electric shock and electrical burns are serious injuries that should receive immediate medical attention.Contacting a first aid attendant plays a crucial role in such injury.Among Australian construction workers it has been observed that first aid training had a positive effect on the occupational safety and health behaviour by improving their desire to avoid occupational injuries [9].

Methods
This is a descriptive cross sectional study conducted in CEB depots situated in Colombo municipal area identified according to the official service area distribution of the CEB [3].Our study population was 120 workers, selected from 450 CEB field level technical workers; skilled, semi-skilled and unskilled, working in 12 CEB depots within the stipulated area.Two stage cluster sampling method was used to select the workers.In the first stage, 8 out of 12 depots were selected randomly.From each depot, a cluster of 15 workers was selected using convenient sampling method.
All workers who were aged between 18 to 60 years, with more than one year work experience in the same work station were considered eligible for the study while office workers and those in supervising grade were excluded.
Ethical clearance was obtained from the Ethics Review Committee of Faculty of Medicine, Colombo.Approval was obtained from CEB authorities.
Primary data was obtained by an intervieweradministered questionnaire.The questionnaire contained sections to assess the incidence of injury, associated factors, knowledge on prevention and first aid.This was developed with the help of a group of experts (CEB supervisors).A pre-test was conducted before data collection to assess the understandability of the questions.
The participants were given a brief introduction about the study prior to obtaining informed written consent.The questions were asked in their mother tongue (Sinhalese and Tamil) and they were encouraged to clarify any doubts in the questions.
There were 12 and 10 closed-ended questions in the knowledge component of prevention and first aid sections respectively.A score of 1 was given to each knowledge-based question and a cut off value was decided to differentiate the subjects with good and poor knowledge with the advice of the CEB supervisors.Subjects with total score more than or equal to 8 in each component were considered having good level of knowledge.
The data collected, was analyzed using the SPSS software (version 20).Socio-demographic information was described using descriptive statistics.Factors associated with incidence of electrical injuries and knowledge on their prevention and first aid were tested using Chi-square test.P values less than 0.05 were considered statistically significant.

Results
The response rate was 100%.All the participants were males and their mean age was 37.19 years (SD=11.08).
The socio-demographic and occupational characteristics of the sample are given in Table 01.Based on this, the calculated incidence of electrical injuries in this cohort of workers is 5.83 per 100 workers per year.
Table 02 shows the factors associated with incidence of electrical injuries.However, we were not able to find any significant association between sociodemographic factors and the incidence of electrical injuries.Work related characteristics such as occupational grade (p=1.0),work experience in current job (p=1.0),work experience in current work location (p=0.6), working hours per day (p=0.6),working days per week (p=0.08),number of training sessions on prevention of electrical injuries (p=0.8),knowledge on prevention (p=1.0) and alcohol consumption (p=0.6) of the workers were also not significantly associated with the incidence of electrical injuries.Table 03 shows factors associated with knowledge on prevention of electrical injuries and factors associated with knowledge on first aid management of electrical injuries.In the study, we found that having 1 to 3 training sessions on prevention and knowledge on prevention has a significant association (p=0.006).We were not able to find any significant association between factors such as educational level (p=0.3),young age of <40 years (p=0.1),alcohol consumption (p=0.9),occupational grade (p=0.2) and work experience (p=1.0) of the workers and their knowledge on prevention.
Occupational grade showed a significant association with their knowledge on first aid management (p=0.01)but none between factors such as age (p=0.07),educational level (p=1.0),alcohol consumption (p=1.0),number of training sessions of first aid (p=0.6) and work experience (p=1.0).contact with wiring transformers or other electrical components and 18% due to contact with electrical current from machine, tools and appliances or light fixtures [10].
According to Trends in electrical injury in the US 1992-2002 article the electricians and their apprentices sustained most electrical fatalities, and electric power installers and repairers ranked third.
They are high risk groups for electrical injuries.They report that 46598 workers were non fatally injured by electricity: 36% due to contact with electric current of machine, tool, appliance, or light fixture and 34% due to contact with wiring, transformers, or other electrical components [11].
Although there are many studies focused on occupational injuries among worker categories like tea plantation and rubber plantation workers in Sri Lanka [12,13] there are only few focused specifically on electrical workers [5].The present study addressed the associated factors of workplace electrical injuries among CEB field level technical workers of the Colombo municipal area and their knowledge on prevention and first aid management at the time of an electrical injury.
Seven fatal injuries (13.2%), 36 reportable injuries (67.9%) and 10 minor injuries (18.9%) among the 53 reported occupational injuries in the CEB occupational settings in Sri Lanka during the year of 2014 [4].In the study among labourers of CEB in Western Province North in 2012, 18 minor (78.3%) and 5 (21.7%) reportable injuries within 6 months reported a prevalence of occupational injuries as 7.6 per 100 workers per 6 months and annual estimated prevalence of 15.2 per 100 workers [5].In comparison, the prevalence in our study was low and all injuries were minor and low voltage injuries.This difference could be due to the small sample size and the retrospective nature of our study.Our study which used a recall period of one year may also contribute to some minor injuries not being recalled.
In comparison to the 2012 study, where a significant association was reported between younger age (20-39 years) and marital status with the prevalence of electrical injuries (p=0.03 and p=0.004 respectively) [5], our study did not find any association between age of the worker or their marital status and the occurrence of electrical injuries.This difference may be due to small sample size of the present study.
Both present study and previous study in 2012 showed higher injury incidences in unskilled occupational grade but neither findings were statistically significant [5].
In a study conducted among Australian construction workers, it was observed that first aid training had a positive effect on the occupational safety and the healthy behavior of workers by improving their desire to avoid occupational injuries [9].However, in our study there was no significant association between the knowledge and prevention of electrical injuries and the incidence of electrical injuries.Occupational grade of the workers and their knowledge on first aid management showed a significant association (p=0.01) in the current study.Higher working experience and number of training sessions associated with higher occupational grade could have accounted for this finding although they were not significant as individual factors.
In this study, the Colombo municipal area was used to include a larger number of employees in an urban setting at a higher risk of electrical injuries.However the findings may not be applicable to all the CEB field level workers in Sri Lanka.
Since this was an interviewer-administered questionnaire, the workers were sometimes reluctant to give the actual data.Self-reporting bias could not be excluded.Since this analysis relied on self-report information, some participants may have underreported injuries because they had not reported about that particular injury to the authorities at the time of the injury or because they had forgotten about minor injuries.Assessing the association between training sessions done before the October 2014 with injuries from October 2014 to October 2015 would have been better than recalling after a period of one year.

Conclusions
Self-reported injury incidence among the workers was about 6% per year and there was no significant association between injury incidence and any of the socio-demographic or work-related characteristics.Knowledge on prevention and first-aid of electrical injuries was satisfactory in a majority.Only the number of training programmes with the knowledge on prevention and occupational grade with the knowledge on first aid management showed significant associations.
Previous studies involving CEB workers have never involved the CEB field level technical staff in Colombo municipal area.In this study, we assessed

Table 01 : Socio-demographic and Occupational characteristics of the sample (n=120)
From October 2014 to October 2015, 6 out of the 120 workers (5%) have faced electrical injuries.One worker had 2 injuries and rest had only 1 injury.All injuries were minor, low voltage electrical injuries.

Table 03 : Factors associated with knowledge on prevention of electrical injuries and with knowledge on first aid management of electrical injuries
CJMS 2017; 54(2):31-37