Work at Height
This page covers the procedures to be followed when engaged in work at height activities.
The Work at Height Regulations 2005 define ‘Work at Height’ as meaning
- “Work in any place, including a place at or below ground level;
- Obtaining access to or egress from such a place while at work, except by a staircase in a permanent workplace, where, if measures required by the Regulations were not taken, a person could fall a distance liable to cause personal injury.”
Work at height includes:
- The use of ladders, step-ladders,
- The use of Mobile Elevating Work Platforms (MEWPs),
- The use of scaffold towers;
- The use of fall arrest equipment
The main hazards associated with work at heights are:
- People falling;
- Things falling onto people. These may occur as a result of inadequate edge protection or securing of people or equipment or due to structural collapse, e.g. caused by component failure or adverse weather.
Risk Assessment & Hierarchy of Control Measures
A risk assessment should be carried out before any work at heights is undertaken. The risk assessment should consider the hierarchy of prevention as follows:
- Avoid working at height where it is reasonably practicable to do so, for example by working from existing platforms, using long reach equipment or lowering trusses for access to equipment:
- Prevent falls of people and objects by carrying out a risk assessment and taking measures to prevent so far as is reasonably practicable people or objects falling. This might include doing the work safely from an existing work place or choosing the right work equipment to prevent falls;
- Mitigate the consequences of a fall by minimizing the distance and choosing suitable fall arrest equipment;
- Give collective protective measures (e.g. guardrails, nets, airbags) precedence over personal protective measures like a safety harness.
The risk assessment should focus on:
- The people (fitness e.g. injuries which could affect ability to climb, scared of heights, susceptible to epileptic fits or other special circumstances)
- The task and activity involved;
- The equipment to be used (e.g. ladders, access towers) including erection and dismantling;
- The environment, poor conditions and slippery surfaces (e.g. weather temperature both hot and cold, wind);
- Application of safe procedures;
- The effect on pedestrian access, rights of way, falling objects;
- Emergency arrangements and rescue plan.
General Precautionary Measures
Falls of persons
In general measures have to be taken where a person could fall a distance liable to cause injury. This is often considered to be about 2m or more. However many injuries also occur when a person falls less than 2m. If, therefore, there are factors which make the risk of injury more likely, precautions will be needed if a fall of less than 2m is possible (e.g. working near a traffic route or above a fragile, sharp or dangerous surface).
There are three main ways of controlling the risk of people falling that must be considered in the order listed:
- Provision of edge protection;
- Use of safety harnesses;
- Maintaining a safe distance (3 metres minimum) by means of a physical barrier (a painted line or bunting is not acceptable), from the edge.
Where edge protection is provided it must extend at least 950mm above the working platform.
There are a number of ways of mitigating the effect of a fall which include minimizing the distance which a person call fall, the use of airbags, safety nets and fall arrest devices which slow down or arrest the decent.
The risk of objects falling onto persons may be controlled by:
- Providing a barrier, to prevent items from slipping or being knocked off the edge of a structure;
- Securing objects to the structure or lifting equipment, e.g. lashing;
- Danger zones should be clearly marked with suitable safety signs, indicating that access is restricted to essential personnel and that hard hats must be worn.
- All objects should be conveyed mechanically or manually both horizontally and vertically, not thrown.
Only those competent to do so, must build structures. They need to have sufficient knowledge, understanding of the risks and precautions and experience in the erection/dismantling of the structure. The skills, knowledge and experience required with depend upon the nature of the structure concerned and the intended use(s).
A wide range of access equipment is available. There are certain considerations that apply to all types of work at height equipment as follows:
- Where equipment is hired it must be fit for purpose. Where contractors are used they must be competent and there must be an appropriate exchange of information about the risks involved.
- All equipment must be properly maintained and regularly inspected.
- Anybody who is expected to use access equipment must be trained and competent to do so. Competence is a combination of appropriate practical and theoretical knowledge, training and experience, which collectively enables a person to undertake the task safely and detect any potential risks, defects in the equipment and recognise any implications for health and safety.
- Precautions must be taken to prevent the fall of objects or persons.
Decision Making Flow Chart
The following diagram should be used to help make decisions on working at height.
Use of Ladders Stepladders and Trestles.
Ladders, stepladders and trestles should be manufactured to appropriate standards as follows:
Glass fibre and aluminium - BS EN 131 Kite marked Industrial;
Aluminium - BS 2037; 1994 Kite marked Class I: Industrial S7377: 1994
Ladders for electrical work should be non-conductive.
All ladders and stepladders must be:
- Stored and handled with care to prevent damage and deterioration.
- Subject to a programme of regular inspection (there should be a marking, coding or tagging system to confirm that the inspection has taken place).
- Checked by the user before use.
- Taken out of use if damaged – and destroyed or repaired.
Any person using ladders or stepladders must be competent.
Ladders are best only used as a means of access to a workplace. They should only be used at a place of work for low risk tasks of short duration. Low risk means that it is not more than 6 metres high, a secure handhold is available all the time, the work involved is of light/minor nature which does not produce significant sideways or outward (for leaning ladders) forces on the equipment.
Ladders should not be used if it is reasonably practicable to use a safer alternative (MEWP, tower scaffold or in permanent cases a staircase).
When using a ladder make sure that:
- The ladder is angled to minimise the risk of slipping outwards. As a rule of thumb the ladder needs to be ‘one metre out for every four metres up’. (Note: rungs are about a 1/3 metre apart).
- The top of the ladder rest against a solid surface. Ladders should not rest on fragile or other insecure materials. If necessary use a stay or standoff resting on a firm surface nearby.
- Both feet of the ladder are on a firm, level footing with rungs horizontal and non-slip.
- All ladders should be secured from falling. This will usually be by fixing at the top, or sometimes the base.
- If the ladder cannot be fixed, a second person foots the ladder while it is being used (this also applies while the ladder is being fixed).
- The ladder extends a sufficient height (about 1m) above any landing place where people will get on and off - unless some other adequate handhold is available.
- Users face the ladder at all times whilst climbing or descending and keep their body centred between the stiles.
- Users always maintain ‘3 point contact’ i.e. two hands, one foot or two feet one hand when ascending or descending.
- Only one person at a time to climb or work from a ladder.
- It is kept away from overhead cables and similar hazards.
Stepladders provide a free-standing means of access, but they require careful use. They are not designed for any degree of side loading and are relatively easily overturned. Avoid over-reaching. People have been killed getting down from workplaces when they have stepped onto the top stop of a stepladder that has then overturned. The top step of a stepladder should not be worked from unless it has been designed for this purpose.
The small platform fitted at the top of many stepladders is designed to support tools, etc., and should not be used as a working place. However some stepladders have been designed with larger lower platforms specially designed for standing on with adequate handrails.
Where practical steel or aluminium stepladders fitted with secure full-length handrails and a top platform with handrails on three sides should be used. These are usually fitted with locking wheels to move them easily and then secure in position when in use.
When using a stepladder make sure that:
- It is on a secure surface, and with due regard to ensuring stability at all times.
- It is long enough for the work in question
- There is enough space to open them out fully.
- They are kept away from overhead cables and similar hazards.
- Any work platform is long enough to work without overreaching.
Section/prefabricated (usually aluminium) scaffold towers can be erected quickly and can give good safe access. However they are involved in numerous accidents each year. These accidents usually happen because the tower has either not be erected properly or had not been used properly.
Tower scaffolds must only be erected by people who are trained and competent to do so, as set out by PASMA or their equivalent. Scaffolds should be used within their designed safe operating limits. As with scaffolding in general, Platforms should be fully boarded out and fitted with edge protection (guardrails and, intermediate rails). There must be a safe means of access to the working platform and the scaffold inspected before use.
Tower scaffolds are often made of lightweight materials and care is needed to ensure that the scaffold remains stable while in use.
The manufacturers of aluminium towers recommend a maximum height, shortest base ratio of
- 3:1 if the tower is to be used outside; increasing to
- 3:5:1 if the tower is used inside.
The use of outriggers to extend the base minimum dimension can allow an increase in height provided the formula of 3:1 or 3:5:1 is followed.
Where practicable the tower should be secured to the structure being worked on. This is essential for heavy work such as grit blasting and water jetting, or where high wind loadings on the tower can be expected.
Follow the manufacturers' instructions for erection, used and dismantling. Have a copy of the instruction manual available – if the scaffold has been hired, the hirer ought to provide this information.
They must be inspected by a competent person before use.
Specific Requirements for Tower Scaffolds
- The tower is vertical and the legs rest properly on firm, level ground
- Any wheels and outriggers are locked – base plates provide greater stability if the tower does not have to be moved.
- With mobile tower scaffolds,
- The wheels are firmly fixed to the base of the uprights so that they cannot fall out when the scaffold is being moved.
- The scaffold is never moved with anyone on the working platform
- Check that there are no power lines or overhead obstructions in the way
- The tower is only moved by pushing at the base and check there are no holes in the ground
- There is a safe way to get to and from the work platform, for example, internal ladders. Climbing up the outside of the tower may pull it over
- Ladders are never placed on tower scaffold working platforms in order to increase the height which can be reached or apply other horizontal loads which could tilt the tower.
- Edge protection, (guard rails and intermediate rails or other suitable barriers) are provided at platforms
- Guard rails are provided on any intermediate platforms and also toe boards where these platforms are being used as working platforms or for storing materials
- The tower is rigidly tied to the structure it is serving or provides other additional support if,
- The tower is sheeted
- It is likely to be exposed to strong winds
- Heavy materials are lifted up the outside o the tower or the tower base is too small to ensure the stability of the height of the platform
- The working platform is not overloaded.
Mobile Elevating Work Platforms (MEWPs)
Mobile elevating work platforms shall be used only after a suitable and a competent person has completed a suitable and sufficient risk assessment.
Only those trained to IPAF or CPCS standards and holding a card to indicate competence, for the type of MEWP being used shall be permitted to operate a MEWP.
When in use there shall be a designated supervisor to ensure a safe system of work is adhered to:
- A harness or fall arrest system shall be used for all Boom type MEWPS.
- Ground stability shall be assessed and regularly checked
- An emergency rescue plan shall be in place for BOOM type MEWPS
- The platform shall be suitable guarding and edge protection
- When in use, the platform shall be subject to a daily inspection check. This includes a daily check of tyre pressures, (when pneumatic tyres are fitted), as the stability of MEWPs is highly dependent on correct tyre pressures in these cases
Specific Requirements for MEWPs
- Ensure the work area is cordoned off by, for example, using cones and warning signs. If there are other vehicles around guidance should be obtained from the Safety Advisor.
- Enter and leave the platform in the fully lowered position using the steps or walkway provided.
- Check for appropriate safety harness lanyards that are attached to secure anchorages inside the cage. Safety devices must never be overridden or interfered with.
- Ensure controls are engaged gently and smoothly
- Check for obstructions or people before raising or lowering the platform
- Ensure that materials and/or tools are not leant against the outside of the platform
- Ensure the MEWP is never used as a jack prop or tie to support other structures or machines
- Ensure it is not used as a crane or for suspending loads beneath the platform
- Check that guardrails, ladders or staging are not used to extend the reach for any purpose.
- Check that hoses and cable are not left hanging free without proper support
- The machine must never be used to tow other vehicles
- Ensure that self-propelled MEWPs are not towed as this can cause serious mechanical damage
- It is only permitted to travel with the platform of a MEWP occupied when the machine has been specifically designed for this purpose. The manufacturer's instructions must be followed carefully.
- Working from or moving a MEWP in the vicinity of overhead high voltage lines, or other overhead lines or cables can be extremely dangerous and essential precautions must be taken.
Fall Protection and Fall Arrest Devices
It is good practice and part of the WAH regulations that collective protection measure such as handrails, safety nets and airbags should have priority over individual protections measures such as safety harnesses and lanyards.
All equipment should be regularly inspected and properly maintained. Checks should be made by the users each time they are used or on a daily basis for collective measures like airbags. All equipment should be subject to detailed inspections at suitable frequencies of about 6 months with interim inspections if they are used in arduous conditions. Safety harnesses and lanyards need special care and more detail is given below.
Safety Harness and Lanyards
Providing a safe place of work and system of work to prevent falls should always be the first consideration. However, there may be circumstances in which is it not practicable for all or any of the requirements for guardrails etc to be provided (for example, where guard rails are taken down for short periods to land materials). Where people may still approach an open edge from which they would be liable to fall a distance which may cause injury, other forms of protection will be needed. In some cases, a suitably attachéd harness and a line could allow safe working.
When using harness and lanyards, remember
- A harness will not prevent a fall – it can only minimise the risk of injury if there is a fall. The shock load to the body when the line goes tight or when they strike against parts of the structure during the fall may injure the person who falls. A shock absorber fitted to the harness lanyards can reduce the risk of injury from shock loads
- Allow for a free fall distance of no more than 2m
- Consider how to recover anyone who does fall
- Anyone who needs to attach him or herself should be able to do so from a safe position. They need to be able to attaché themselves before they move into a position where they relying on the protection provided by the harness.
- The harness lanyard should be attached above the wearer where possible. Using running lines or inertia reels can provide extra free movement. Any attachment point must be capable of withstanding the shock load in the event of a fall – expert advice may be needed.
Inspection of Harness and Lanyards
A regime for the inspection of harnesses and lanyards should be established. The regime should include: -
- The harness and lanyards to be inspected (including their unique identification)
- The frequency and type of inspection (pre-use checks, detailed inspection and, where appropriate, interim inspection)
- Designated competent persons to carry out the inspections
- Action to be taken on finding defective harnesses and lanyards
- Means of recording the inspections
Training of users and a means of monitoring the inspection regime to verify inspections are carried out correctlyIt is essential that the person carrying out any inspection is sufficiently independent and impartial to allow them to make objective decisions and has appropriate and genuine authority to discard defective lanyards. This does not mean that competent persons must necessarily be employed from an external company, although many manufacturers and/or suppliers offer inspection services and training in the inspection of their products.
Harnesses and Lanyards should be subject to pre-use check and detailed inspections and (as appropriate) interim inspections. Competent persons must carry these out, to identify defects or damage that may affect the safety.
- These checks are essential and should be carried out each time before the lanyard is used.
- Pre-use checks should be tactile and visual. The whole lanyard should be subject to the check, by passing it slowly through the hands (e.g. to detect small cuts of 1mm in the edges, softening or hardening of fibres, ingress of contaminants). A visual check should be undertaken in good light and will normally take a few minutes.
- These more formal, in-depth inspections should be carried out periodically at minimum intervals specified in the inspection regime. It is recommended that there is a detailed inspection at least every six months.
- For frequently used lanyards it is suggested that this is increased to at least every three months, particularly when the equipment is used in arduous environments.