Manual handling injuries, such as back strains, shoulder injuries and hernias, come from lifting, lowering, carrying, pushing and pulling loads, and from repeating awkward movements. They are among the most common workplace injuries in Canada. The most effective way to prevent them is to change the task, the load or the workplace so the risk is lower, rather than relying on workers to lift perfectly every time.
What makes a task risky
Strain injuries rarely come from one factor alone. Risk grows as these combine:
- Force. Heavy loads, stiff valves, carts that are hard to start or stop.
- Posture. Bending, twisting, reaching overhead or far in front, kneeling or working in cramped spaces such as crawl spaces and mechanical rooms.
- Repetition and duration. Doing the same movement many times or for a long shift without a break or a change of task.
- Load characteristics. Bulky, unstable, slippery or uneven loads, and loads without good handholds, such as drums, panels and bags.
- Environment. Slippery or uneven floors, stairs, poor lighting, cold that stiffens muscles, and tight time pressure.
- Individual factors. Fatigue, previous injury and unfamiliarity with the task.
Many provinces have specific requirements for assessing the risk of musculoskeletal injury and controlling it, in addition to the general duty to assess hazards. Check the rules in your province.
Assessing manual handling tasks
Start by listing tasks that involve handling loads and looking at injury and first aid records, near misses and worker comments. Then observe the tasks as they are actually done. For each task, note the weight and size of the load, the starting and ending heights, the distance carried, how often it is done, the postures involved and the conditions. Workers who do the job are the best source of information about which parts hurt.
Several recognized assessment tools give a structured way to score tasks and compare improvements. Whatever tool you use, the aim is the same: find the tasks with the highest risk and change them first. Record the assessment as part of your wider hazard assessment and control process.
Controls, from most to least effective
Eliminate or redesign the task
- Have materials delivered directly to where they are used, by forklift or crane rather than by hand.
- Order materials in smaller or lighter packages.
- Change the process so loads do not have to be lifted from the floor or above shoulder height.
Mechanical aids
- Carts, dollies, pallet jacks and drum handlers
- Hoists, vacuum lifters and lift tables
- Adjustable work benches and stands that bring work to waist height
- Valve wheel tools and torque aids for stiff equipment
Mechanical aids must be suitable, maintained and available where the work happens, or workers will go back to lifting by hand.
Workplace layout
Store heavy items between knee and shoulder height. Keep walkways clear and floors dry and even. Reduce carry distances and eliminate steps where you can.
Work organization
Use team lifts for loads that cannot be mechanized, with one person calling the lift. Rotate tasks, schedule breaks, and avoid rushing. Allow time for new and returning workers to build up to heavier tasks.
Training
Train workers to recognize risky tasks, use the equipment provided, plan a lift, test the load, keep it close to the body, avoid twisting and ask for help. Training supports the other controls but cannot make an unsafe task safe on its own.
Lifting technique is not the whole answer. Programs that rely only on teaching workers to bend their knees tend to have limited results. Changing the task and the equipment produces more lasting reductions in injuries.
A worked example
A facilities team regularly changes air filters in rooftop and penthouse air handling units. Filters arrive in large boxes at the loading dock, are carried up two flights of stairs, and are then pulled from low racks inside each unit while the technician kneels on a grated floor. Several technicians report sore backs and knees.
Observing the task shows where the risk comes from: carrying bulky boxes on stairs, kneeling and reaching to the back of low racks, and twisting to pass filters out through a narrow access door. Working through the controls:
- Redesign. Have the supplier deliver smaller boxes, and use the freight elevator or a hoist to get them to the roof level instead of the stairs.
- Mechanical aids. Keep a cart at the roof level for moving filters between units.
- Layout. Stage new filters on a bench at waist height next to each unit, not on the floor.
- Organization. Split the work across two people so one passes filters out while the other receives them, and spread the change-outs over more days.
- Equipment. Provide knee pads and a kneeling mat for the part of the task that still requires it.
The team then checks back with the technicians after the next change-out to see whether the soreness reports have dropped, and adjusts again if not.
What to record in a manual handling assessment
| Item | What to note |
|---|---|
| Load | Weight, size, shape, handholds, stability |
| Movement | Start and end heights, carry distance, pushing or pulling force, twisting |
| Frequency | How often, for how long, and the breaks or task changes in between |
| Environment | Floor, stairs, space, lighting, temperature |
| Workers' input | Which parts of the task they find hardest and what they suggest |
| Controls | What will change, who is responsible, and when it will be checked |
Common mistakes
- Buying a lift aid but storing it somewhere inconvenient, so nobody uses it
- Assessing the task as it is described in the procedure rather than as it is actually done
- Fixing the heaviest lift and missing a lighter task that is repeated hundreds of times a shift
- Treating a team lift as a permanent solution for a load that could be mechanized
Early reporting
Strain injuries often start as discomfort that workers ignore. Encourage early reporting of aches and pains, and treat each report as a signal to look at the task, not as a complaint. Early action can prevent a minor problem from becoming a lost-time injury. A culture where people feel safe raising concerns helps here, as described in Psychological safety and hazard reporting.
How ehZee can help
We assess manual handling tasks on site, recommend practical changes to tasks and equipment, and build them into your safety program. Manual handling is part of our lift safety and fall arrest service, and also fits within broader safety program development.
Common questions
Is there a maximum weight a worker can lift?
There is no single safe weight for everyone. Risk depends on how the load is lifted, how often, from what height and in what posture. Some provinces and guidelines give reference values, but an assessment of the actual task is more useful than a single number.
How do we know whether the changes worked?
Watch the task again after the change, ask the workers whether it is easier, and track discomfort reports, first aid cases and injuries for that task over the following months. If workers have drifted back to the old way, find out why: the aid may be too slow, too far away or unsuited to the load.
Do back belts prevent injuries?
Evidence that back belts prevent lifting injuries in healthy workers is weak. They should not be used instead of changing the task or providing mechanical aids.