Canadian Occupational Safety

16 Canadian Occupational Safety www.cos-mag.com By Amanda Silliker A bout 15 years ago, a man was working on a sewer line around a butcher building in Manitoba. At the time, the plant let all the unused cow guts go down into the sewers, so the worker was up to his hips in cow innards trying to complete a repair job. "After that, the guy took a pay cut and went and became a snowplow driver," says Troy Winters, senior health and safety offi cer at the Canadian Union of Public Employ- ees in Ottawa. Rats, syringes, tampons, dirty dia- pers and human feces are just some of the things sewer workers face on a daily basis. Basically, anything that gets fl ushed down a system — from the toilet, kitchen sink or industrial workplace — sewer workers will come in contact with. "You get some pretty strong and unpleasant odours and substances and it's not the easiest thing," says Michael Pigott, works superinten- dent at the City of Charlottetown. "You need to have a strong stomach. It's not for everyone that's for sure. These guys have their jobs cut out for them." Aside from doing stomach- churning jobs, workers who work on sewer lines — such as inspectors, maintenance workers and techni- cians — complete high-risk tasks every day. "It's probably one of the most dangerous (jobs) that our CUPE members do," says Winters. "There's lots of potential hazards down there and you never know what is down in the manhole when you open it up." Workers exposed to sewage face a signifi cantly increased risk for airway symptoms, chronic bronchitis, toxic pneumonitis (infl ammation of lung tissue) as well as central nervous system symptoms such as headaches, unusual tiredness and concentration diffi culties, accord- ing to the 2002 report "Work Related Symptoms Among Sewage Workers: A Nationwide Survey in Sweden" published in Occupational & Environ- mental Medicine. Further, they also face increased risk for gastrointesti- nal symptoms and joint pains. BIOHAZARDS There are lots of potential infections that can come from working around whatever gets fl ushed down the toilet. The most serious viral risk for sewer workers is hepatitis and the most serious bacterial risk is tetanus. Workers need to make sure their vac- cines are up to date. The City of Charlottetown pro- vides hepatitis A and B vaccines as well as tetanus vaccines for its work- ers who are exposed to raw sewage, says Pigott. They are also supplied with all kinds of personal protective equipment (PPE) — gloves, boots, coveralls, half-mask respirators, rain suits, hard hats and eyewear — to protect them from the biohazards. Respirators are particularly impor- tant to ensure nothing can splash up and get in the nose or mouth. "The respirators we use are good quality with the cartridges on them and we are fi t tested for them. We have a good secure fi t on our face — which is really important," says Blaine Parkman, utility foreman at the City of Charlottetown. Workers should keep all their equipment at work so they don't bring any potential contaminants home. When designing the utility stations, there should be a clearly defi ned "dirty area" where workers can change out of their PPE and a "clean area" where they can put on their street clothes to avoid contami- nation, says Winters. "If you think through the fl ow of materials, where the equipment is coming from and going to, a few basic steps will certainly help decrease the chance that somebody will be re-exposed to something after it was supposed to be cleaned," he says. And the workers' trucks should be considered as contaminated as the work area, so when they change out of their PPE back in the station, they have to make sure not to get back in the truck again. CONFINED SPACES Manholes, lift stations and sewer lines themselves are all confi ned spaces, which come with many con- cerns. These spaces can sometimes become defi cient in oxygen due to oxygen being used up by the decom- position process and combustion processes, such as cutting and weld- ing. Oxygen-defi cient atmospheres may cause a person to feel lethargic and potentially lose consciousness. In Alberta, for example, the minimum concentration of oxygen required in a worker's breathing air is 19.5 per cent by volume. Below this level, air supplying respirators must be worn. Hydrogen sulphide (H2S) is a highly toxic gas that can be present in sewers. It can be created by the decomposition of organic matter. Low concentrations have a smell of rotten eggs, but the odour is not present in higher levels. Concentra- tions of H2S above 500 parts per million (ppm) will cause uncon- sciousness in a few seconds and can lead to death if action is not imme- diately taken. In April 1969, three workers in Portage La Prairie, Man., went to a It's a dirty job, but someone's got to do it. Sewer workers encounter THE WORLD BELOW

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