Watch your step21 May 2012
The death of a 61-year old man in Washington who hit his head as he tripped from a crane deck led the state’s department of labour and industries recommend the following ways to avoid falls from height.
The accident was investigated by Todd Schoonover, Eric Jalonen and Randy Clark of Washington state department of labor and industries. They prepared the following gudiance. They hope to make sure all workers can get down from a crane safely, regardless of physical ability.
Construction equipment operators, riggers and maintenance personnel are the most at risk of a fall.
While not necessarily fatal, injuries to backs and knees may be lifelong and deteriorate quality of life and ability to work.
In this case the victim had difficulty dismounting from the crane turntable deck, but problems could equally arise with any areas where workers may be expected to perform work.
Washington State Fatality Assessment and Control Evaluation, (FACE), came upu with ways to prevent similar occurrences in the future. It has put together the following guidelines for all users of mobile cranes and other mobile equipment.
1. Training/hazard identification
Decreasing the risk is about identifying the most risky activity and letting employees know.
This usually means creating a written company policy with a crane mounting and dismounting procedure, such as:
• Maintain three points of contact - two hands and one foot, or one hand and two feet - with the equipment or ground at all times.
• Face toward the equipment, both when mounting and dismounting, for improved contact and balance.
• Never jump, as this could lead to a slip or an ankle/knee injury.
• Prevent slips by wearing clean, slip-resistant footwear and looking for mud, sand or ice.
• Mount and dismount equipment only where steps, ladders, and handrails/handholds are provided.
• Use a hand line and bag/bucket to raise or lower equipment so hands are free to climb.
• Make a procedure not only for the cab but also for any other part where work is carried out.
The next step is putting it in action by training and supervising employees.
2. Buy or refurb cranes with rungs and steps
Whether or not you have a training program, you should at least have a crane with the right steps and handholds, low enough for people to access, because it is more effective to provide the right equipment than to enforce wide scale changes in employee behavior.
The best mobile cranes for safety are the ones that have easy access by steps, ladders, handrails, handholds, platforms and guardrails that allow workers to enter and exit the cab and other crane parts.
Equipment access systems should be designed for the ease and safety of the user. If these systems are absent or poorly designed, then there is an increased risk of a fall.
Crane owners can look at existing access equipment to make sure it is low enough for current employees to reach. Employees should able to easily reach steps, handrails, and handholds, both during entry and exit or mounting and dismounting.
Employers can also get employee input on access when buying new equipment or retrofitting older equipment.
Large employers can review injury data to see whether injuries are occurring within their employee base.
When purchasing or retrofitting older equipment be sure that the access systems are designed with sound safety engineering principles. Ask the equipment's manufacturer or distributor about safe access systems.
This may be available from distributors or directly from the manufacturer, so long as it is compatible with the crane.
"After market access systems are available, but must fit the equipment, suit the user's needs, and incorporate elements of safe access design," says Jalonen.
FACE says "Many falls from mobile equipment and vehicles can be attributed to nonconformance to established design standards and guidelines."
When checking whether your manufacturer's crane to see if it has the best access equipment, you may want to check it against a list from 2007 which supplies a list of basic access requirements.
The guidelines from American Society of Mechanical Engineers' consensus standard ASME B30.5-2007 Mobile and Locomotive Cranes are not comprehensive description of all criteria to be considered when designing and implementing safe access systems, but is meant to give an idea of what to have.
Some minimum criteria for mobile equipment and vehicle access systems are:
• It should be easy to use them without special training.
• They should minimize protrusions that could cause a user to trip.
• All surfaces should be non-slip.
• The shortest expected user should be able to easily reach the first step from the ground.
• Components of the access system should be placed to allow and encourage the user to follow the three-points of contact method and face toward the equipment while ascending/descending or mounting/dismounting.
• Two handholds or handrails (handrails are preferable) should be accessible to the shortest expected user from the ground and while ascending or descending.
• Handrails/handholds should be placed along the access system to provide continuous support so as to allow the user to maintain balance.
• Steps should be coordinated with properly positioned handrails and handholds so that three points of contact can be maintained.
• Handrails/handholds should have smooth surfaces.
• Step design should provide the user with natural foot placement or should be clearly visible to the user while descending.
• Steps or rungs should allow the midpoint of the shoe, not just the toe, to rest solidly on the step or rung.
• Steps should be wide enough to stand on with both feet.
• Steps should be uniform in size and shape.
• Steps should be designed to allow minimal accumulation of mud and debris.
• The height and depth between steps should be uniform.
3. Repair and replace dysfunctional access equipment
Steps ladders and handrails get dirty or break, and employers should include this in any checks. Checks to surfaces may include ensuring that walking and working surfaces of the equipment have anti-slip surfaces, that these work, and that they are clean.
Employees should be encouraged to take action at the earliest stage when they observe a breakdown, whether by notifying a maintenance person or the employer. They should be advised to remove accumulations of rainwater, ice, and snow.
4. Consider older workers' safety
The advancing age of employees in the industry often changes employees' ability to keep up with physical tasks.
"Older workers are at higher risk of fatal falls, and workers 55 and older have the highest rate of fatal falls. The average height of fatal falls for older workers is about a third shorter than the average height at which younger workers die from falls," says Jalonen.
Many employers nonetheless wish to maintain such employees as they bring their valuable experience and expertise to the workplace. Employers can take measures to ensure that their employees as they age will still be able to perform their jobs.
Again, keeping adequate steps and handholds, enough of them and within reach, is essential to making access safer and easier for older workers. Consideration must be taken not only for the condition of decreased physical strength but for vision, low flexibility, instability of gait, and other health conditions.
5. Manufacturers should increase access offerings
FACE has concluded that the availability of mobile equipment access systems is a key factor in determining whether users are able to perform their work activities safely.
Poorly designed systems can be a major contributor to falls, and so they should be designed to eliminate or minimize fall hazards.
"Equipment access steps, ladders, handrails, and handholds should be designed and placed in accordance with sound design principles taking into account the safety needs of all potential users," says Jalonen.
"The design and placement of access system components determine how users will interact with them and whether their interactions result in easy and safe access to and from equipment or whether they result in unsafe actions or falls. Improvements in design are more effective than relying on changing worker behavior.
Manufacturers, too, need to take note of the study. FACE found it concerning that not all manufacturers consider ergonomics when designing equipment.
FACE says, "If key components of an access system are missing, cannot be safely reached, involve an awkward posture, provide inadequate footing or handhold, or require use of a part of the equipment not designed as part of the access system (such as stepping on a vehicle tire), then risk of potential injury to users is increased."
Workers are not to blame for jumping and causing injury to themselves or others, even fatal, when there is no step for getting down in the first place, FACE says.
"Risk taking behaviour by workers, such as jumping down from equipment, may be the result of lack of or inadequate or poorly placed steps, handholds, and handrails."
Designers and manufactures of mobile equipment, as well as their clients, may look to available guidance as to design of access equipment, FACE says.
Guidance includes the National Institute for Safety and Health's "Prevention through Design" initiative and the American Society of Safety Engineers' Prevention through Design guidelines when creating access systems.
These measures are intended to encourage business leaders, designers, and manufacturers to "design out" or minimize hazards so as to prevent occupational injuries and fatalities, says FACE.
FACE strongly suggests that manufacturers not already doing so provide safe access systems as a standard part of their mobile cranes.
6. Safety regulations need more thinking out
Researchers have noted that occupational health and safety regulations and design standards are 'incomplete, inadequate, vague, or non-specific, providing only general specifications and guidelines'.
That means that these days it is up to users to evaluate their access systems to accommodate their workforce's needs.
FACE proposes that more specific future government regulations and industry standards should be developed.
Research could be into personal characteristics, anthropometry, demographics, and injury experience of the user population that is leading to the falls.
"The results of this research should be used to inform equipment designers and manufacturers, industry associations, standards boards, and occupational health and safety regulators," says FACE.