By Michael Biddle, Working at Height Association of Australia chair and Capital Safety Australia and New Zealand managing director
A total of 275 people died as a direct consequence of a fall from a height in the period 2003 to 2012 in Australia – around 11 per cent of total fatalities. Surprisingly, an additional 227 people died in the same period as a consequence of being hit by a falling object; about 9 per cent of total fatalities, according to Safe Work Australia.
Aside from fatalities, drops and falls also represent a significant volume of general injuries. Falls from a height represented more than 7400 workers compensation claims in 2012, with a median lost time of 7.2 weeks. Additionally, more than 4200 claims were recorded from injuries created by falling objects, with a median lost time of 4.2 weeks.
Given these two mechanisms of injury are the third and fourth ranked cause of death and significant causes of injury, the question is, are these inevitable? Or, with the right approach, are they preventable? Most would answer “yes”, provided there are sufficient education, awareness and safety management systems in operation. The prospect of reducing these incidents is, therefore, very high.
The cost of drops
The cost of lost time in both health outcomes for workers and lost productivity time is concerning. Importantly, it is also the workers’ families that bear the brunt of the impact of these injuries, through loss of income and medical expenses that may follow from the incident.
In addition, the loss of the items themselves can be costly. If objects are dropped over water, into mud, machinery, down holes and other difficult-to-reach places, they are effectively a sunk cost needing replacement. While anyone can drop a tool, the chances are vastly increased when other environmental factors come into play.
For example, high wind, rain, greasy environments and even working with ill-fitting gloves can make the challenge of tool security an issue. For a comparatively low cost and a different attitude to containment, these costs can be avoided.
Using gravity as a work aid
Certain job tasks and industries use gravity to their own advantage. For example, the demolition of a building might allow for materials to be dropped to a lower level using gravity means, rather than a controlled mechanical descent process such as a crane and debris bucket. Many buildings are also clad in protective mesh or netting to contain debris and prevent it from causing injury or escaping from the building envelope. In most cases, these work methods are less safe than alternatives. They rely on the principle of containment, rather than prevention of falls in the first place. On most major metropolitan work sites, the incidence of this is thankfully infrequent. In locations where there is less supervision or regulator present, the same cannot be said.
Hierarchy of control
Risk management, utilising the principle of the ‘hierarchy of control’, is considered to be the best approach to preventing injury. Engineering a hazard out altogether or utilising alternative means of access to minimise fall risks is best practice. Wherever possible, preventing the fall of a person or tools through the use of guarding or barriers is the most appropriate means of protection possible as they remove the fall of people or objects altogether in the first place.
Primary vs secondary consequence
When people consider the use of fall protection equipment, they are primarily concerned about protecting themselves or their workers and contractors. Items such as anchoring devices, full-body safety harnesses, a fall arrest lanyard or self-retracting lifeline to connect between the two, and some defined rescue means to allow for safe descent are the core components of a fall protection safety system. In this sense, they are concerned about the ‘primary consequence’ of a fall. When it comes to items such as tools and equipment they use for their job, these are often, however, afterthoughts. These items are equally as important to consider if they fall, as dropping them can have secondary consequences on the people working below them, or the innocent bystanders in the near vicinity. Although nuts and bolts, spanners and other lightweight equipment is small in physical size, once the combination of gravity is added, the outcomes can hold grave consequences.
The physics of drops
People don’t realise the impact forces that are generated in a dropped object. A 3kg item dropped 15m could create an impact force of more than 500kg. A 1kg item dropped 50m will hit the ground at a little more than 112km/h (excluding any air resistance). Even with some form of protection, the result of being struck by an item of relatively low weight can be significant.
The use of general personal protective equipment (hard hats for example) can be a good front-line barrier to reduce the impact of a dropped object if it is relatively light and not dropped from a very high location.
Their effectiveness is, however, limited when they are exposed to falling bricks, rocks or other heavy items such as hand tools, or indeed even greater heights. A hard hat does not provide any protection for other parts of the body such as shoulders and arms.
The economic loss of equipment coupled with the injury cost to a person working below is high. Even if there are no people in direct danger underneath walkways, dropped objects still have the capacity to damage surrounding equipment and machinery. Subsequent repairs can be both costly and time consuming. But this risk is also easily managed if a comprehensive management program for dropped object risk is implemented.
Methods of containment
Here is an example list of some of the methods of containing dropped objects:
- Lower the working platform to the ground/ perform all work on a structure at ground level and then lift it into position once complete rather than taking the tools and equipment to height;
- Kick boards and handrails should be fixed on scaffolding, platforms and walkways. By using additional closed mesh solutions, plywoods or other solid surface materials, coverage can be provided for all the gaps through which items can potentially fall;
- Utilise safety mesh or rated barrier netting (with debris lining) in areas outside walkways and underneath conveyors, walkways platforms and along building/structure perimeters to prevent the drop of materials to a lower level;
- Utilise tool lanyards, tool cinches, tool pouches, tethering devices, holsters, tool buckets and other drop containment devices to secure tools and other items during work at height activities; and
- Provide worker education on the risks and outcomes of dropped objects and provide them with the means by which they can minimise that risk.
Preventing dropped object falls is not just the responsibility of the safety supervisor or the site owner. It is everyone’s responsibility to manage these risks because the impact might not be personal, but it might affect your co-workers and unseen bystanders. We all have to work together to stop the drop.