For the past several years, injuries and fatalities resulting in working fall risk positions has increased and contributed to around 17% of all claims made by FEM policyholders. In the past three years alone, twelve employees lost their lives, and motor vehicle incidents were cited as the cause of the majority of fatalities.
This article focuses on aspects involving employees working at fall risk position and how the industry can improve and ensure all employees working at fall risk positions are safeguarded.
Access equipment
Many injuries result from failures or falls involving access equipment which has been incorrectly selected, erected, used or maintained. Access equipment is frequently used for short duration and emergency work without full consideration of a safe method of work. Each task should be assessed, and a suitable means of access chosen based upon an evaluation of the work to be done, the duration of the task, the working environment (and its constraints) and the capability of the person or people carrying out the task.
There are many different types of access equipment. This section covers the following:
· Ladders, stepladders and trestles
· General access scaffolds
· Scaffold towers
· Suspended cradles
· Personal suspension equipment (abseiling equipment and boatswain’s chairs)
· Mast-elevated work platforms
· Mobile elevating work platforms (MEWPS)
Other highly specialised equipment is available, and the general principles will apply to their use. Usually they have been specially designed for particular tasks and manufacturers’ information should be used in operator training.
General principles
Accidents using access equipment occur because one (or more) of the following common problems have not been controlled in advance, or was thought to be an acceptable risk under the circumstances:
· Faulty design of the access structure itself
· Inappropriate selection where safer alternatives could have been used
· Subsidence or failure of base support
· Structural failure of suspension system
· Structural failure of components
· Structural failure through overloading
· Structural failure through poor erection/inspection/ maintenance
· Structural failure through overbalancing
· Instability through misuse or misunderstanding
· Overreaching and overbalancing
· Climbing while carrying loads
· Slippery footing — wrong footwear, failure to clean
· Falls from working platforms and in transit
· Unauthorised alterations and use
· Contact with obstructions and structural elements
· Electrical and hydraulic equipment failures
· Trapping by moving parts
Ladders, stepladders and trestles
The key points to be observed when selecting and using this equipment are as follows.
Ladders
1. See whether an alternative means of access is more suitable. Take into account the nature of work and duration, the height to be worked at, what reaching movements may be required, what equipment and materials may be required at height, the angle of placement and the foot room behind rungs, and the construction and type of ladder.
2. Check visually whether the ladder is in good condition and free from slippery substances.
3. Check facilities available for securing against slipping
a. tied at top, secured at bottom, or footed by a second person if no more than 3 m height access is required.
4. Ensure the rung at the step-off point is level with the working platform or other access point, and that the ladder rises a sufficient height above this point (at least 1.05 m or five rungs is recommended), unless there is a separate handhold.
5. A landing point for rest purposes is required every 9 m.
6. The correct angle of rest is approximately 75° (corresponds to a ratio of one unit horizontally at the foot for every four units vertically).
7. Stiles (upright sections) should be evenly and adequately supported.
8. Ladders should be maintained free of defects and should be inspected regularly.
9. Ladders not capable of repair should be destroyed.
10. Metal ladders (and wooden ladders when wet) are conductors of electricity and should not be placed near or carried beneath low power lines.
11. It is important to ensure that ladders are positioned the correct way up. Timber pole ladders often have stiles thicker at the base than at the top and should have metal tie rods underneath the rungs. Metal ladders often have rungs with both flat and curved surfaces — the flat surface is the one on which the user’s feet should rest.
Stepladders
1. Stepladders are not designed to accept side loading.
2. Chains or ropes to prevent overspreading are required, or other fittings designed to achieve the same result. Parts should be fully extended.
3. Stepladders should be levelled for stability on a firm base.
4. Work should not be carried out from the top step, and preferably not from the top third.
5. Overreaching should be avoided by moving the step- ladder — if this is not possible, another method of access should be considered.
6. Equipment should be maintained free from defects. Regular inspection is required.
7. No more than one person should use a stepladder at one time.
Working platforms and trestles
1. Trestles are suitable only as board supports.
2. They should be free from defects and inspected regularly.
3. Trestles should be levelled for stability on a firm base.
4. Platforms based on trestles should be fully boarded, adequately supported and provided with edge protection where appropriate.
5. Safe means of access should be provided to trestle platforms, usually by a stepladder.
6. Working platforms in construction work must by law be no less than 600 mm in width, so many older trestles may no longer be suitable to support such platforms as they will be too narrow.
General access scaffolding
There are three main types of access scaffold commonly constructed from steel tubing or available in commercial patented sections. These are:
1. Independent tied scaffolds, which are temporary structures independent of the structure to which access is required but tied to it for stability.
2. Putlog scaffolds, which rely upon the building (usually under construction) to provide structural support to the temporary scaffold structure through an arrangement of putlog tubes (with special flattened ends) placed into the wall.
3. Birdcage scaffolds, which are independent structures normally erected for interior work which have a large area and normally only a single working platform.
The key points to be observed when specifying, erecting and using scaffolds are:
1. Select the correct design with adequate load-bearing capacity.
2. Ensure adequate foundations are available for the loads to be imposed.
3. The structural elements of the scaffold should be provided and maintained in good condition.
4. Structures should be erected by competent persons or under the close supervision of a competent person, in accordance with any design provided and with applicable Regulations and Codes of Practice.
5. All working platforms should be fully boarded, with adequate edge protection, including handrails or other means of fall protection, nets, brick guards and/or toe- boards to prevent materials or people falling from the platforms.
6. All materials resting on platforms should be safely stacked, with no overloading.
7. Adequate and safe means of access should be provided to working platforms.
8. Unauthorised alterations of the completed structure should be prohibited.
9. Inspections of the structure are required, prior to first use and then at appropriate intervals afterwards, which will include following substantial alteration or repair, after any event likely to have affected stability, and at regular intervals not exceeding seven days. Details of the results should be recorded on an inspection form.
Scaffold towers
Scaffold towers are available commercially in forms comparatively easy to construct. They may also be erected from traditional steel tubing and couplers. In either form, competent and trained personnel are required to ensure that all necessary components are present and in the right place. Many accidents have occurred because of poor erection standards; a further common cause is overturning.
The key points to be observed in the safe use of scaffold towers are:
1. Erection should be in accordance with the manufacturer’s or supplier’s recommendations.
2. Erection, alteration and dismantling should be carried out by experienced, competent persons.
3. Towers should be stood on a firm level base, with wheel castors locked if present.
4. Scaffold equipment should be in good condition, free from patent defects including bent or twisted sections, and properly maintained.
5. The structure should be braced in all planes, to distribute loads correctly and prevent twisting and collapse.
6. The ratio of the minimum base dimension to the height of the working platform should not exceed 1:3 in external use, and 1:3.5 in internal use, unless the tower is secured to another permanent structure at all times. Base ratios can be increased by the use of out- riggers, but these should be fully extended and capable of taking loads imposed at all times.
7. Free-standing towers should not be used above 9.75 m unless tied. The maximum height to the upper working platform when tied should not exceed 12 m.
8. A safe means of access should be provided on the narrowest side of the tower. This can be by vertical ladder attached internally, by internal stairways or by ladder sections designed to form part of the frame members. It is not acceptable to climb frame members not designed for the purpose.
9. Trapdoors should be provided in working platforms where internal access is provided.
10. Platforms should be properly supported and fully boarded.
11. Guardrails, toe boards and other appropriate means should be provided to prevent falls of workers and/or materials.
12. Mobile scaffold towers should never be moved while people are still on the platform. This is a significant cause of accidents.
13. Ladders or stepladders should not be placed on the tower platform to gain extra height for working.
Suspended access (cradles)
A suspended access system includes a working platform or cradle, equipped with the means of raising or lowering when suspended from a roof rig.
The key points to be observed in the safe installation and use of this equipment are:
1. It should be capable of taking the loads likely to be imposed on it.
2. Experienced erectors only should be used for the installation.
3. Supervisors and operators should be trained in the safe use of the equipment, and in emergency procedures.
4. Inspections and maintenance are to be carried out regularly.
5. Suspension arrangements should be installed as designed and calculated.
6. All safety equipment, including brakes and stops, should be operational.
7. The marked safe working load must not be exceeded, and wind effects should also be considered.
8. Platforms should be free from obstruction and fitted with edge protection.
9. The electrical supply is not to be capable of inadvertent isolation, and should be properly maintained.
10. Adverse weather conditions should be defined so that supervisors and operators know what is not considered acceptable.
11. All defects noted are to be reported and rectified before further use of the equipment.
12. Safe access is required for the operators and unauthorised access is to be prevented.
13. Necessary protective measures for those working below and the public should be in place before work begins.
Mast-elevated work platforms
Generally, this equipment consists of three elements:
· Mast(s) or tower(s) which support(s) a platform or cage
· A platform capable of supporting persons and/or equipment
· A chassis supporting the tower or mast
The key points to be observed in the erection and use of this equipment are:
1. Only trained personnel should erect, operate or dismantle the equipment.
2. The manufacturer’s instructions on inspection, maintenance and servicing should be followed.
3. Firm, level surfaces should be provided, and outriggers are to be extended before use or testing, if provided.
4. Repairs and adjustments should only be carried out by qualified people.
5. The safe working load of the equipment should be clearly marked on it, be readily visible to the operator and never be exceeded.
6. Raising and lowering sequences should only be initiated if adequate clearance is available.
7. The platform should be protected with edge guardrails, toe boards and provided with adequate means of access.
8. Emergency systems should only be used for that purpose, and not for operational reasons.
9. Unauthorised access into the work area should be prevented using ground barriers.
10. Contact with overhead power cables should be pre- vented, by preliminary site inspection and by not approaching closer than a given distance. This distance can be obtained in respect of the particular power lines, from the power supply company, where necessary.
Mobile elevated work platforms (MEWPS)
A wide variety of equipment falls into this category, ranging from small, mobile tower structures with self-elevating facilities, to large vehicle-mounted, hydraulically- operated platforms. Some of their uses may involve high risk situations — these have been identified by the HSE as where:
· There are protruding features which could catch or trap the carrier/platform;
· Nearby vehicles or mobile plant could foreseeably collide with the MEWP;
· The nature of the work may mean operators are more likely to lean out, or are handling work pieces which may move unexpectedly; and
· Unexpected or rapid movement of the machine, or overturning, is possible.
The key points to be observed in their use are:
1. Operator controls should be at the platform level, with over-ride at ground level for emergencies.
2. There should be a levelling device fitted to the chassis to ensure verticality in use.
3. Supervision should prevent use of the equipment during adverse weather conditions.
4. Outriggers, where provided for increased stability, should be fully extended and locked into position before the equipment is used/raised, in accordance with the manufacturer’s instructions. The wheels may also require locking.
5. Materials and/or persons should not be transferred to and from the platform while in the raised position.
6. Training is required for operators before they are allowed to use the equipment in field conditions unsupervised.
7. Operators and others on the platform who are wearing safety harnesses should secure them to the inside of the platform cage.
8. When fitted, scissor mechanisms require the provision of adequate fixed guards, so as to prevent trapping of the operator or others during raising or lowering. (Note that this does not apply where interlocked proximity sensors are fitted to cut power when resistance is felt between the scissor arms.)
9. The equipment requires regular inspection, servicing, maintenance and testing in accordance with the manufacturer’s instructions.
The general principle is that fall prevention is far more effective than fall protection, which often involves personal protective equipment. Reliance on people to make the ’right’ decision about wearing personal protective equipment has be shown by events to be unsatisfactory — they forget, decide not to wear it in view of the expected short exposure time, or do not wear or use it correctly. The first stage in fall prevention is during the design process, which influences the construction method. Early erection of stairways avoids the need to fence off open stairwells, and also provides safe access to the next level. Are so many floor slab penetrations necessary? Could the design be changed to allow a single common service duct?
The legal requirements for preventing falls by those working at fall risk position are to be found in the the Construction Regulations 2014.
Neil Enslin | Occupational Health and Safety Manager
Sources:
· Principles of Construction Safety - Allan St John Holt BA, FIOSH, RSP
· Construction Health and Safety handbook
· Occupational Health and Safety Act and its Regulations
· The performance approach to construction worker safety and health
· Sans 10085 scaffolding
