Telescopic Gate Safety - White Paper 3First Edition
Safety requirements for powered telescopic gates
Jeremy Procter, Managing Director of Procter Automatic Gates, explains the safety requirements relating to powered telescopic gates. This advice will help architects, specifiers and users to understand the issues and ensure that gates comply with the necessary legislation, regulations and standards.
Powered telescopic gates are available in a variety of configurations, sizes, styles and material specifications to suit different applications. Furthermore, there is a choice of access control system and safety measures, which makes this type of gate extremely versatile for domestic, commercial, industrial and public sector premises.
Compared with the more traditional alternatives of swing gates and sliding gates, telescopic gates require less space when open. In common with sliding gates, telescopic gates achieve a higher level of security than swing gates and can be used on very wide openings, particularly if a bi-parting pair of gates is used.
Unfortunately there have been a small number of accidents involving powered gates, mostly resulting in injuries but there have also been fatalities. In addition, there have been numerous ‘near misses’ that could easily have resulted in injuries. Powered gates have always had to comply with the European Machinery Directive and be CE marked to indicate their compliance but, with no 'CE Police' to monitor the market, the Directive's requirements have not been enforced. In the past, therefore, some powered gates have been installed without the necessary safeguards in place. As of 29 December 2009, there is a new Machinery Directive (2006/42/EC) that is more explicit about the duties of national governments regarding enforcement.
Legislation and Regulations
Here in the UK, Statutory Instrument 2008/1597 The Supply of Machinery (Safety) Regulations 2008 came into force on 29 December 2009 to implement the new European Machinery Directive 2006/42/EC. The 2008 Regulations replaced The Supply of Machinery (Safety) Regulations 1992, as well as the 1994 and 2005 amendments.
Newly installed powered gates (telescopic, sliding, swing and bi-folding gates) fall within the scope of the Machinery Directive and must therefore be CE marked as machinery. Strictly speaking, suppliers in the UK must comply with the requirements of The Supply of Machinery (Safety) Regulations 2008, though these essentially restate the requirements contained in the Machinery Directive. There are European standards that are harmonised to the Machinery Directive; while compliance with these is not mandatory, doing so is considered the best way to demonstrate that the Essential Health and Safety Requirements of the Machinery Directive have been met (the harmonised standards are said to provide a 'presumption of conformity'). However, see the note below regarding standards and the state of the art.
Where powered gates are installed at a workplace they also fall within the scope of the following:
- Provision & Use of Work Equipment Regulations 1998 (PUWER 98)
- The Health and Safety at Work etc Act 1974
- The Management of Health and Safety at Work Regulations 1999
Because powered gates are CE marked in accordance with the requirements of the Machinery Directive, they do not need to be CE marked to the Construction Products Directive as well.
As implied above, the most important product-related standards for powered telescopic gates are those that are harmonised to the Machinery Directive 2006/42/EC, a full list of which is available via the European Commission website:
|BS EN 953:1997 +A1:2009*||Safety of machinery. Guards. General requirements for the design and construction of fixed and movable guards|
|BS EN ISO 12100:2010||Safety of machinery. General principles for design. Risk assessment and risk reduction|
|BS EN ISO 13849-1:2008||Safety of machinery. Safety related parts of control systems. General principles for design|
|BS EN ISO 13855:2010||Safety of machinery. Positioning of safeguards with respect to the approach speeds of parts of the human body|
|BS EN ISO 13856-2:2013||Safety of machinery. Pressure-sensitive protective devices. General principles for design and testing of pressure-sensitive edges and pressure-sensitive bars|
|BS EN ISO 13857:2008||Safety of machinery. Safety distances to prevent hazard zones being reached by upper and lower limbs|
|BS EN 12444:2001||Industrial, commercial and garage doors and gates. Resistance to wind load. Testing and calculation|
|BS EN 12445:2001||Industrial, commercial and garage doors and gates. Safety in use of power operated doors. Test methods|
|BS EN 12453:2001||Industrial, commercial and garage doors and gates. Safety in use of power operated doors. Requirements|
|BS EN 12604:2000||Industrial, commercial and garage doors and gates. Mechanical aspects. Requirements|
|BS EN 12605:2000||Industrial, commercial and garage doors and gates. Mechanical aspects. Test methods|
|BS EN 12635:2002+A1:2008||Industrial, commercial and garage doors and gates. Installation and use|
|BS EN 12978:2003+A1:2009||Industrial, commercial and garage doors and gates. Safety devices for power operated doors and gates. Requirements and test methods|
|BS EN 13241-1:2003+A1:2011||Industrial, commercial and garage doors and gates. Product standard. Products without fire resistance or smoke control characteristics|
|Industrial, commercial and garage doors and gates. Product standard. Products without fire resistance or smoke control characteristics||Safety of machinery. Electrical equipment of machines. General requirements|
Some of the standards applicable to powered gates were drafted many years ago and no longer represent the state of the art. In the light of investigations into recent accidents, the Health and Safety Executive (HSE) has challenged some aspects of the standards. Consequently, some of the current advice and recommendations from the HSE and the Door & Hardware Federation (DHF), which is the UK trade body representing manufactures, exceeds the requirements laid down in the standards.
Protecting againast hazardsArchitects, specifiers and users are unlikely to purchase copies of the standards listed above, hence it is worth highlighting the main hazards that should be addressed. BS EN 12604 includes a list of mechanical hazards in section 4.5 and also has a more extensive checklist in Annex A. The mechanical hazards are:
There could also be electrical, hydraulic and other hazards, depending on the design of the gate and its operating mechanism. Note that the accepted principle when addressing hazards is to design them out where practicable, then provide guards (eg physical guards around hazardous parts of machinery, and safety light barriers to detect the presence of people in potentially hazardous areas) and, finally, reduce any residual hazards to an acceptable level by measures such as warnings and release mechanisms for use in the event of a person becoming trapped.
Powered telescopic gates, like other types of powered gate, possess considerable momentum when in motion. They must therefore be designed as far as reasonably practicable to eliminate the mechanical hazards; where safety devices such as pressure-sensitive safe edges and photocells are used, they must be installed and theEx control system designed such that the gates react in a safe way when an obstruction is detected.
For the physical guarding, the designer needs to consider the harmonised standards relating to reach distances and minimum gaps to avoid crushing. Note, however, that machinery safety standards are not always written with a view to protecting children; for example, the scope of BS EN ISO 13857, Safety of machinery. Safety distances to prevent hazard zones being reached by upper and lower limbs, excludes children under the age of 14 except for upper limbs reaching through openings, but it should be assumed that children will have access to the gates and misuse them (eg by attempting to ride on them while they are in motion).
Examples of measures that can be taken to design-out and safeguard against hazard include:
- Force limitation measures to ensure that an obstruction will not experience forces greater than the values specified in BS EN 12453. This applies to the leading edge of the slave leaf and also other crushing, shearing and drawing-in points such as those between the master leaf and the fixed structure and between the master and slave leaves
- Because of the lost motion in telescopic gates, it is common to reduce the speed for the final metre of travel
- As with sliding gates, telescopic gates are normally controlled in such a way that they stop and reverse if an obstruction is detected
- A pressure-sensitive strip and/or a protected infrared beam on the leading edge of each leaf
- Safety strips on the leading edges of the inside and outside of the guide posts and receiving post, connected to the control box
- Sheet infill or mesh to protect the gap between the guide posts, inside and outside. Mesh should be sized in accordance with BS EN ISO 13857 table 5
- Infrared safety beams either side of the gate to detect the presence of pedestrians, vehicles and other obstructions
- Enclose the run-back area of the gate by fencing 1m away from the gate, or additionally use mesh of a suitable aperture size at least 2m high, positioned in accordance with BS EN ISO 13857 table 5 to prevent hand/arm access
- Position the run-back line of the gate at least 1m from the external fence, or ensure that the fence is infilled with additional mesh cladding of a suitable aperture size in accordance with BS EN ISO 13857 table 5 for the length of the gate run-back to prevent hand/arm access.
More detail is provided in standards such as BS EN 12453 and BS EN ISO 13857.
Before a powered telescopic gate is specified, designed or installed, it is essential that a risk assessment is performed (likewise, a risk assessment can reveal any shortcomings in the safety of existing gates). BS EN 12453 identifies factors that can influence the level of risk and, in particular, three categories of users and four types of control for which the safeguarding can be different (the following is paraphrased from the standard):
- A limited group of people who are trained to operate a gate that is not in a public area
- A limited group of people who are trained to operate a gate that is in a public area
- Any person who is free to operate a gate that is located in a public area
- Hold-to-run switch located in sight of the gate
- Impulse switch (press and release to operate) located in sight of the gate
- Impulse switch not located in sight of the gate
Depending on the combination of users and controls, the required safety measures range from nothing to either:
- force limitation and a means to detect a person or obstacle on the floor at either side of the gate; or
- a means of presence detection to ensure that a person cannot be touched by the gate under any circumstances
Given that most gates are accessible on at least one side by members of the public (passers by), the majority of powered gates require the highest category of safety measures.
Although the subject of fail-safe controls is covered by the appropriate standards, it is worth highlighting this requirement in this present White Paper for those readers not familiar with control system design. With a fail-safe design, the failure of a safety device - such as an optical sensor or a pressure-sensitive strip - should result in the gate control system defaulting to a safe condition. Such a component failure may be due to damage (from a vehicle collision or vandalism, for example) or a mechanical or electrical failure of the device itself. In the event of a 'fail safe' situation occurring, the gate is likely to cease operating in its normal automatic mode, depending on the design of the control system. While this may be inconvenient for users, it is essential in order to maintain safety at all times. Powered gates will normally have a means by which they can be opened and closed in the event of the power supply being disconnected, but on no account should any attempt be made to bypass safety devices.
A gate's safety-related detection devices, such as optical sensors and pressure-sensitive strips, are often vulnerable, so these should be vandal-proofed as far as reasonably practicable. For example, only sufficiently robust devices should be used, their location should discourage attack, accessible fasteners should be of tamper-resistant types and, if a CCTV system is installed, a camera can be trained on the gate as a further deterrent.
See also Appendix A, Examples of powered telescopic gate hazards and protective measures.
More information about the design of powered sliding gates is available in the DHF publication Guide to gate safety legislation and standards (see Further information below).
In general the manufacturer will install the gate, as it is only during installation that the gate becomes fully assembled and can therefore be assessed and CE marked. It is vital that the gate is installed correctly if it is to perform as intended and with the required level of safety; this includes both the mechanical and electrical aspects, together with any associated access control system.
Architects and specifiers are strongly advised to use installers that are accredited by organisations and schemes such as DHF Safety Assured, CHAS (Contractors Health & Safety Scheme), Constructionline, Safe Contractor, Secured by Design, and that adhere to an ISO 9001 quality management system.
When a new powered telescopic gate is installed, it should be CE marked to indicate compliance with the requirements of the Machinery Directive. In addition, the organisation that CE marks the gate (which may be the manufacturer or the installer, depending on the circumstances) should provide an EC Declaration of Conformity showing with which harmonised standards the gate complies, plus a set of instructions that includes operation, maintenance, checking correct functioning, and residual risks. As part of the CE marking process, a Technical File should have been assembled, but there is no legal obligation for the manufacturer to provide a copy of this.
MaintenanceAs with any machinery, powered telescopic gates require periodic maintenance. Today's gates are designed for a long, trouble-free life, but Procter Automatic Gates recommends that its gates are serviced a minimum of every six months, depending on the level of usage and the types of safety device installed. This servicing not only maintains the operating mechanism and guides in good condition but also checks the operation of the safety features. If the site owner/operator does not wish to undertake this work or does not possess the necessary instrumentation to test the safety features, facilities management companies can sometimes undertake the work or the gate manufacturer may offer a maintenance service.
The Door & Hardware Federation (DHF) has published a Guide to gate safety legislation and standards, which is available to download from the Procter Automatic Gates website or on request.
Three Safety Notices have been published by the Health and Safety Executive (HSE), all of which can be accessed from the HSE's website at www.hse.gov.uk:
- FOD WSW 1-2010, Risks to pedestrians from crushing zones on electrically powered gates. This identifies potential safety risks to pedestrians and lists actions required by gate manufacturers and installers, construction companies, and estates and/or facilities management companies
- FOD 7-2010, Risks to pedestrians from crushing zones on electrically powered gates - 2. This reinforces and updates the information provided in FOD WSW 1-2010
- OPSTD 1-2011, Powered perimeter gates. This provides advice to landlords, commercial owners or facilities managers of properties with powered gates.
- Powered gate basics: http://www.hse.gov.uk/work-equipment-machinery/powered-gates/basics.htm
- Powered gate responsibilities: http://www.hse.gov.uk/work-equipment-machinery/powered-gates/responsibilities.htm
- Powered gate safety: http://www.hse.gov.uk/work-equipment-machinery/powered-gates/safety.htm
- Powered gate FAQs: http://www.hse.gov.uk/work-equipment-machinery/faq-powered-gates.htm
- High-quality gates direct from the manufacturer
- All types of powered and automatic gates: telescopic, sliding, swing and bi-folding
- A wide range of design options and material specifications, so customers can opt for anything from standard designs to fully bespoke gates
- A cost-effective and dependable service that covers the site survey, design, manufacture, installation, commissioning, CE marking and maintenance
- Prices that are very competitive against those from European suppliers of powered gates
- Installation by fully trained, expert teams in accordance with ISO 9001 quality standards and industry-leading site safety standards and accreditations
- Gates that are CE marked and fully compliant with the requirements of the Machinery Directive 2006/42/EC
- Reassurance of the highest standards of safety, quality and service through the company's membership of the Door & Hardware Federation (DHF) and accreditation as a DHF Safety Assured installer.
Prestigious gate installations by Procter include the Ports of Harwich, Barry and London, Leeds St James Hospital, Clogau Gold, Panasonic, Bournemouth and Bristol Airports, River Island, Carphone Warehouse and Sony
To discuss any requirements for powered gates, email [email protected]
Appendix A - Examples of powered telescopic gate hazards and protective measures