Dr Chris Ide provides an overview of the health and safety hazards that workers in the utilities and offshore sectors can face, looking at issues specific to the different types of workplaces involved, as well as the problems that are common to all of them.
Public utilities — those organisations that supply our homes, workplaces and other establishments with power (electricity and gas), telecommunications and water/sewage services — employ about 7 per cent of the workforce in UK. It’s difficult to be precise about the numbers, because although most of the utilities are allocated fairly specific categories in the statistics compiled by government,1 there will always be a degree of overlap between the categories.
Nonetheless, in September 2012, about 124,000 people were employed in the electricity industry, 212,000 in telecommunications, and about 46,000 in water and sewage services. Oil and Gas UK reckons that about 32,000 are employed in the production of oil and gas, with a further 207,000 in the supply chain.2
When considering the occupational-health needs of any group of workers, a useful starting point is to look at what it is that causes them to die, particularly if it causes them to perish in greater numbers than expected. When I began my career in occupational medicine almost 30 years ago, just about all the utility companies were public-sector organisations. Thus, they were characterised by significant personnel bureaucracies, which often included occupational-health services. They also seemed to have a low turnover of employees, so this made them ideal subject organisations for mortality studies.
Electricity workers
A survey of almost 84,000 employees of the old Central Electricity Generating Board of England and Wales reassuringly reported that, generally speaking, fewer deaths occurred than expected. The Standardised Mortality Rate for the population as a whole (which was predominantly male) was 83 — i.e. where 100 deaths would be expected, only 83 occurred. However, there were more than four times as many deaths from mesothelioma than would have been expected, and deaths from brain cancer and male breast cancer occurred almost twice as commonly.3
These findings were generally mirrored by other studies. Although one American paper found increased all-cause mortality, including cardiovascular and malignant disease,4 other research based on the experiences of US,5 Canadian6 and French7 workers demonstrates that, generally, mortality rates are less than expected. However, concern still remained about the possible link between some cancers —particularly leukaemia and brain tumours, as well as other degenerative neurological diseases, such as Parkinson’s and Alzheimer’s — and occupational exposure to electromagnetic fields. Once again, at the level of intensity to which most employees are exposed, there would seem to be no particular relation between occupation and significant disease, with the exception of Amyotrophic Lateral Sclerosis, another chronic degenerative brain disease.8-11
For fatal occupational injuries, a report based on the experience of almost 130,000 employees of five American electrical power companies over a 36-year period demonstrated a predominance of electrocution, murder and falls, which tended to be concentrated among certain groups of employees.12
Observations such as this led to the setting up of surveillance of occupational illness and injury data for the electric energy sector,13 which aimed to gather more detailed information to identify areas for intervention to improve health and safety. This demonstrated that the rates of injury varied almost 50-fold across the industry, and that three of four companies who reduced their workforces had a noticeable increase in injury rates.14
Further work from this group has shown that line and maintenance workers were more likely to have severe strain and sprain injuries, and that this risk was particularly concentrated in older employees.15 By contrast, neck injuries were most likely to occur in male tradesmen under 30 years old, and more than two thirds resulted in one day, or less time lost from work.16
Gas workers
For gas workers, studies of occupational mortality are generally reassuring. A study of American gas-distribution workers published in 1983 concluded that the population studied did not have an excessive all-cause death rate, and deaths due to heart disease, all cancers and cancers of the respiratory and digestive tract were no more than would be expected. While this confirmed the results of the only previous study, the authors advised that their results should be interpreted with caution because of the small population involved (118 deaths in 1410 people), and the use of a general, rather than working, population as a control.17
By contrast, a study of Swedish gas workers found an increased death rate from cardiovascular and respiratory diseases, and violence. The heart and chest diseases became more common with greater length of employment, suggesting an occupational link. However, although cancer rates were increased, the rise was not significant.18
A much larger survey of almost 52,000 American gas employees followed up for over 25 years found fewer deaths than expected and, in particular, no increase in rates for cancers in general, or specific tumours.19 It is important to remember that, in all of these studies, workers involved in the earliest part of the projects would have likely been involved in the production of ‘town gas’, produced by the destructive distillation of coal, which would be associated with the production of known carcinogens like polycyclic aromatic hydrocarbons, etc. For many years, this has been replaced by natural gas, consisting mainly of methane.
Telecomms workers
For this group, most of the research relating to mortality seems to concentrate on the extent to which deaths are attributable to various cancers, particularly those that have putative associations with exposures to electromagnetic fields. Taking a broader view, work published in 2004 described lower than expected all-cause mortality in television workers, especially with regard to cardiovascular and malignant diseases, although some sites did have more cancers than expected. Unfortunately, the article itself was in Russian!20
More than 30 years ago, falls and handling accidents contributed substantially to the injury toll among middle-aged telephone engineers.21 Almost 20 years afterwards, Macaulay found that there had been little change.22
Sewage workers
The occupations mentioned thus far could only exist in the modern world. Sewage disposal, however, has a much more ancient lineage. Thackrah, in his book The effects of the arts, trades and professions on health and longevity, published in 1831, writes that: “With the exception of asphyxia, these men are not, as far as we could ascertain, subject to any serious disease, neither are they short-lived.”23
However, he does add a footnote to the effect that it might be worse in other places, and refers readers to Ramazzini’s book De Morbus Artificum Diatriba, in which the author describes the distress of a worker, cleaning the Ramazzini household’s ‘House of office’, concerning his eyesight. It is then noted that several blind beggars have previously followed this occupation.24
More recent research shows that there has been a degree of improvement, since a paper reporting the mortality of Swedish sewer workers almost three hundred years later showed that the number of deaths overall, and due to cardiovascular causes in particular, were at least a quarter less than would have been expected when compared to the general population. Overall cancer mortality was roughly what would have been expected, although brain, gastric and renal tumours occurred more frequently than expected.25
However, a survey of Parisian sewage workers demonstrated a rather higher than expected death rate, particularly with regard to liver disorders and infectious disease.26 These findings were, to some extent, mirrored by another Swedish paper.27 These effects were potentially attributable to aerosols, etc. containing infectious agents such as bacteria and viruses, not to mention various chemicals that get dumped down drains. However, work by Italian researchers demonstrated little difference in rates of infection with Hepatitis A virus, and controls.28
Wild et al also commented that the liver diseases tended to be those associated with excess alcohol consumption, while the deaths from infectious diseases tended to occur after the sewage workers had left their jobs; deaths from suicide were also considerably higher than expected, and mortality from infectious diseases did not generally occur until after the person concerned had left their job.26
These disparate groups of workers seem to — generally speaking — have a better quality of life than the general population. This is partly due to the ‘healthy worker effect’, which stipulates that working populations, other things remaining equal, tend to be more healthy, since the more seriously ill are either not working, or unemployable. Also, the oil, gas and telecommunication industries tend to draw more heavily on skilled or professional groups, who perform better, in general, in mortality surveys. They may also already have safety advisors and occupational-health staff who have carried out more thorough risk assessments, and can argue the case for investment in health and safety more convincingly, as well as a workforce whose members and representatives are prepared to become more involved and cooperate in these endeavours.
Generally speaking
When I first set out to compile this article the difficulty I anticipated was the wide range of organisations that operate in the utilities and offshore sectors, all offering different hazards. While driving to a clinic and seeking inspiration, that old Glen Campbell song ‘Wichita lineman’ came on the radio, which, I am sure, readers of my vintage will remember well: “I am a lineman for the county/I drive the main road/searching the line for/another overload…”. Eureka!
I realised that many of these workers will face common hazards — for example, outside work in all weathers. The vagaries of climate will require adequate protection in cold, wet and windy weather to avoid hypothermia, as well as sturdy waterproof footwear to reduce slipping hazards, while at the other extreme, protecting the skin from sunburn must not be forgotten. If work takes place in grassland, clothing will also need to be able to protect against tick bites, particularly those associated with the spread of Lyme disease.
The workers will often use powered tools, possibly giving rise to a vibration hazard. The magnitude of this can be reduced by choosing equipment with the lowest levels of vibration compatible with the expeditious performance of the task. The tools need to be properly maintained and, if the level of vibration approaches the Exposure Action Value of 2.5 metres per second squared, then time limits for exposure need to be set and adhered to, and the requirement for health surveillance considered. Wherever there is a vibration hazard, there is generally a noise issue, too, and that must be managed through a combination of reducing exposure, appropriate hearing protection, and audiometric health surveillance, if relevant.
The tools may generate dusts, which can be either irritant or toxic, so the particles require suppression. If that is impracticable, adequate personal protective equipment needs to be provided, with workers and supervisors trained in its use and maintenance. Lastly, given that some raw materials like oil and gas are sometimes sourced in politically unstable parts of the world, recent events in Algeria concentrate the mind on the need for protection of life and liberty.
Workers in any of the utilities may need to enter confined spaces, either at or below ground level. In order to get in, they may need to lift heavy manhole covers, and face the possibility of breathing atmospheres that are either oxygen-deficient, or contain toxic gases, such as carbon monoxide or hydrogen sulphide. While hydrogen sulphide has its characteristic ‘rotten egg’ smell, the olfactory sense can become fatigued, impairing the ability to detect it, thus increasing the chances of asphyxiation.
If water is around, then infection with diseases like leptospirosis (Weil’s disease) must be considered, particularly if rodents are known to be in the vicinity. A good preliminary risk assessment will allow the preparation of safe working techniques, which will reduce dependence on gas detection devices, and facilitate rapid extraction and evacuation of any casualties, should they occur. That said, the provision of adequate rescue equipment, first aid and awareness of the availability of the emergency services should not be neglected. Finally, be prepared, since all sorts of nasties, such as insects and used needles, can be found in confined spaces.
Utility workers are often required to climb poles and pylons, so fall-prevention measures are important. Physical fitness will also help protect workers from harm, since suppleness will make it easier to enter and leave confined spaces, and work at height. Employees who are prone to vertigo and sudden bouts of loss of consciousness should be excluded from this type of work, at least until they can demonstrate good control of their underlying condition — for example, being able to hold (other things remaining equal) a class 2 driving licence.
In conclusion, the duties of a safety advisor for a utilities company offer a wide range of challenges, which, if met and mastered, can help protect the lives and well-being of an important group of workers.
References
1 www.ons.gov.uk/ons/dcp171766_287890.pdf TABLE JOBS03 (Sept 2012, accessed 20th. January 2013
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Dr Chris Ide is an occupational physician and regular contributor to SHP.
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