Engaging in sewage-related work poses potential infection risks for workers, encompassing tasks with untreated sewage, sludge, effluent water, grit, septic tank waste, and biosolids. Here's how WorCover Queensland suggests managing these risks and safeguarding workers:
Understanding 'Sewage': Sewage is wastewater originating from homes, industries, and businesses. After undergoing treatment, it's either reused or released into land, waterways, or the ocean.
Infection Risks: Workers handling human waste or sewage may encounter waterborne diseases due to exposure to disease-causing organisms (pathogens) in treated sewage, biosolids, and recycled water. Skin contact, inhalation, or unintentional ingestion are potential pathways for pathogen exposure, emphasizing the need for robust personal hygiene and protective gear.
Occupational Exposure: Occupational exposure to sewage can result in illnesses caused by pathogens in body fluids, enteric microbial pathogens, opportunistic pathogens, microbial endotoxins, and parasites. These illnesses encompass gastroenteritis, skin infections, hepatitis A and B, and leptospirosis.
People at Risk: Those at risk include wastewater treatment plant workers, laboratory workers, contractors, sewer system inspectors, maintenance personnel, plumbers, irrigators, and workers involved in sewage waste transport or land application of biosolids.
Risk Management: Workers and management collaboration is key to minimizing risks. Workers must adhere to health and safety instructions, utilize equipment properly, follow safe work policies, and report hazards or work-related issues. For businesses, adherence to the Work Health and Safety Act 2011 is crucial:
Ensure Safe Systems:Implement safe work practices, provide information, training, and supervision, and encourage a consultative and cooperative environment.
- Personal Protective Equipment (PPE):Provide and maintain suitable PPE, ensuring systems for inspection, maintenance, cleaning, and storage are in place.
- Occupational Immunizations:Support or provide occupational immunizations based on risk.
Four Steps to Manage Risk:Effectively manage risks associated with sewage work by:
- Conducting a risk assessment considering exposure likelihood and consequences.
- Implementing suitable control measures.
- Maintaining and regularly reviewing these control measures.
A commitment to these steps ensures a safer work environment, aligning with the principles of the Work Health and Safety Act 2011.
The first step is to identify possible hazards.
Inspect your business
Think about your workplace and note where your work environment or processes create the risk of exposure to sewage.
Talk to your workers
Talk to your workers to find out if they have any health and safety concerns. A confidential survey could give workers who are less likely to speak out in public an opportunity to provide feedback.
Review available information
Read the relevant legislation and codes of practice. Research how other workplaces have managed risks.
Find more information on how to identify risks in How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB).
The second step is you identify a potential risk, make a risk assessment to identify:
- if there is a risk to you or others
- whether any effective control measures are already in place
- what actions you could take to control the risk
- how urgently you should act.
A risk assessment can include looking at:
- the nature of the work and how this exposes workers and others
- whether the work is required or if it can be rescheduled to a time when the risk of exposure is reduced
- the frequency and duration of contact.
Use this risk assessment template (DOCX, 0.02 MB) to guide and record your assessments.
The third step is assessing the risk, put control measures in place.
The hierarchy of control is a step-by-step approach to eliminating or reducing risks. It ranks risk controls from the highest level of protection and reliability through to the lowest and least reliable protection. Implement control measures in this order:
- Level 1: Get rid of the harm and prevent the risk.
- Level 2: Replace the hazard with something less harmful, separate people from the hazard, or change work processes or the physical work environment.
- Level 3: Use administrative controls to reduce exposure (such as limiting time spent in a hazardous area) or use personal protective equipment (PPE) to protect people from harm.
Eliminating exposure is the most effective way to protect workers, but this may not always be possible. Where you can’t eliminate risk, minimise it.
Minimise contact with sewage
For example:
- Avoid direct contact with sewage or recycled water and unnecessary exposure to sprays and aerosols.
- Use remote-controlled robotic cameras to inspect sewer pipelines.
- Install barriers and screens to contain sewage.
- Minimise the time spent in areas where sewage is being agitated or disturbed.
- Manage sewage aerosols and biosolid dust with ventilation controls.
- If using heavy equipment to apply biosolids, fit the cabin with air conditioning and maintain filters and seals.
- Clean any tools or equipment after use.
Vaccinate
Workers who have regular contact with untreated sewage should be vaccinated against hepatitis A and B and have current tetanus vaccination. A combined hepatitis A and B vaccine is available for workers who have regular contact with sewage debris such as used needles and syringes. Where required because of risk, provide free vaccination to employees. A vaccination program may also include agreement to vaccination as an employment pre-requisite. Learn more about the recommended vaccinations for people who work with sewage.
Keep the workplace clean
- Clean contaminated surfaces, equipment and tools with clean water and detergent.
- Disinfect heavily contaminated surfaces and equipment after cleaning. Disinfectants need a minimum contact time to be effective. They may not work properly in the presence of organic matter such as sewage, so clean surfaces before applying a disinfectant. Alternatively, use a product that is both a detergent and a disinfectant.
- Separate clean and dirty equipment to prevent cross-contamination.
- Avoid cleaning methods that disperse aerosols (such as high-pressure washing and compressed air).
- Control pests such as rodents and insects.
Maintain personal hygiene
- Wash hands thoroughly with soap and clean water immediately after working, after contact with sewage and contaminated equipment, and after removing personal protective equipment (PPE).
- Keep fingernails short and scrub nails with soap after work.
- If using a waterless hand sanitiser make sure it contains an alcohol content of at least 60 percent. Only use it on visibly clean hands. Wash your hands with soap and water at the first chance.
- Avoid touching your face with contaminated hands or gloves. Don’t eat, drink or smoke when working with sewage.
- Before eating, remove soiled work clothes and wash your hands and face thoroughly. Only eat in designated areas away from sewage-contaminated areas.
- Check your skin before starting work and cover any cuts and other broken skin with a clean, dry dressing. If you get a wound at work, clean and cover it straight away.
- If untreated sewage gets on your skin or in your eyes, nose or mouth, wash the area thoroughly.
- Remove work clothes at the end of the shift and wash or shower. Change clothes before you leave. If possible, leave your work clothes at work.
- Keep work clothes separate from other clothes. Wherever possible, separately launder and store work clothes. Clean work clothing with commonly available laundry disinfectant products or a 0.05% chlorine solution (1 part bleach to 100 parts water).
Employers or PCBUs:
- Provide workers with adequate washing facilities (PDF, 0.57 MB). Include clean running water, soap and paper towels.
- Provide field workers with portable hand washing facilities.
- Use handwashing signage to remind workers to wash their hands.
- Provide workers who have significant contact with sewage access to showers and change rooms.
- Provide workers with first aid facilities, clean eating facilities and drinking water.
Personal protective equipment (PPE)
Basic PPE for working with sewage:
- work clothes (coveralls or clothes with sleeves and long pants)
- enclosed liquid-repellent shoes or rubber boots with non-slip soles
- water-proof gloves (always wear them when cleaning pumps, filters or screens and when handling effluent, recycled water or biogrit)
- eye protection (when the eyes are exposed to dust, flying particles or splashes).
Additional PPE:
- Wear liquid-repellent coveralls, a disposable or reusable respirator and/or a splash-proof face shield as needed when dealing with raw sewage or confined spaces.
- Wear a properly fitted (PDF, 0.86 MB) particulate respirator (such as a disposable P2 respirator or higher) if exposed to sewage aerosols and biosolid dust.
- Use suitable respiratory protection if there are hazardous chemicals or oxygen deficiency.
Procedures and reporting
Have clear procedures for reporting incidents, injuries and diseases. Tell workers to visit a medical practitioner if they have any of these symptoms:
- stomach cramps
- fever
- nausea
- diarrhoea
- vomiting
- yellowing of the skin
- symptoms of breathlessness, chest tightness and wheezing
- redness and pain in the eyes
- skin rash and/or pain.
Advise staff to tell the medical practitioner they work with sewage, human effluent, biosolids or recycled water.
Have a documented procedure on what to do if a worker is grossly exposed to sewage (such as a splash to the eyes or mouth).
Information, instruction, training and supervision
Provide workers with information on:
- health risks from contact with sewage and the signs and symptoms of waterborne diseases
- appropriate hygiene practices, particularly the importance of handwashing and correct laundry practices
- use, storage, cleaning and disposal of contaminated PPE and equipment
- reporting procedures for damaged PPE and equipment, incidents and potential illnesses or symptoms
- safe work procedures relevant to the site
- occupational vaccinations
- selecting and using PPE
- first aid.
The last step is Risk management is an ongoing process.
Check regularly to make sure the control measures are working. If you find problems, go through the steps again, review the information, and decide whether you need new controls.
Under the work health and safety laws you must review the controls:
- when you become aware that a control measure is not working effectively
- before a change that might create a new risk
- when you find a new hazard or risk
- when your workers tell you that a review is needed
- after a health and safety representative requests a review.
You can find a list to help you find any issues in the How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB).