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 | | SECURITY DOORSETS | | | Adams Rite | | 27/05/2008 | | | Security is a wide ranging subject and the meaning of the term ‘security doorset’ is primarily in the mind of the person using the term related to their own particular needs and objectives.
A ‘security doorset’ may be required to prevent the escape of prisoners or perhaps dangerously mentally ill patients where the ‘security’ element might mean consideration of removable parts that might be used as a weapon or other features related to the risk of self harming. In the case of mentally ill patients consideration must also be given to the security of staff in the event of a need to vacate a building (say) in the event of a fire with minimal risk to both patients and staff. In other cases the term ‘security doorset’ will apply to doorsets that are intended to prevent access to a building or part of a building for the purpose of protecting persons and property.
Additionally, the term ‘security doorset’ might be used in connection with doorsets that are tested for bullet resistance or blast resistance by reference to test and performance standards not considered in this document. In this document, we are only concerned with ‘security doorsets’ that are intended to deny access through a doorway, i.e. security by way of access prevention.
The primary purpose of any doorset is to provide a means for ‘traffic’ to pass from one side of a wall to the other. Other performances e.g. fire resistance, sound attenuation, security etc. may be considered as secondary performances. Secondary performances can generally only be achieved when the door is in the closed position. In the case of access prevention there is an immediate conflict between the primary performance requirement and a need for an essential secondary performance.
Some client organisations have designed and developed their own security doorsets, and have tested the constructions using test methods that reflect their particular needs. This method generally applies to Government organisations such as the Ministry of Defence in respect of military establishments. The ‘need to know’ element is particularly important in relation to security and in these cases a manufacturer might simply be given drawings showing the essential manufacturing details to be satisfied. The manufacturer may not know what particular level or class of performance might be achieved or how the doorset design might have been tested. The manufacturer would generally have no liabilities with regard to the subsequent performance of the doorsets except in so far as the manufactured product complies with the client designs. Similar considerations might apply to other client organisations e.g. some banks and financial institutions may have designs developed in consultation with security advisors that may be manufactured and tested under the same circumstances. The design and testing of these products may be influenced by insurance considerations and are usually associated with wider security provisions.
Generally security doorsets will fall into two basic categories:
1/ Doorsets intended to be resistant against opportunist (non professional) attack.
2/ Doorsets intended to be resistant against professional attack.
In the United Kingdom we tend to describe doorsets in the second category as being ‘burglar resistant’ while the first category is generally referred to as ‘forced entry’ resistant. However, proposed European standards use the term ‘burglar resistant’ to cover all categories.
Opportunist attack is defined as being an attack normally associated with the casual or opportunist intruder. These attacks result where an opportunity presents itself with no particular regard to the likely success that a breach of the security might bring. The anticipated level of force is not excessive and the tools used to gain entry are more likely to include common hand tools and levers.
It is further anticipated that the ‘villains’ involved in such attacks are likely to avoid noise and unnecessary risk and that a limited time will be spent in attempting entry.
A professional attack is defined as being an attack by a more experienced professional burglar with a more focused aim and with knowledge of the likely reward that a breach of the security might bring. The professional attack is generally planned with some knowledge of the security elements that may need to be defeated. Organised crime syndicates may be involved. Noise and time issues may be of lesser concern and the tools used to breach the security may include power tools.
The basic categories are further sub divided to reflect a level of risk. The ‘security’ ratings currently used in the United Kingdom are published by reference to website – ‘Guide to Security Standards for Doors and Windows’. The grading is related to test methods that include static, dynamic and manual test methods. The static and dynamic tests are repeatable and are carried out using calibrated laboratory equipment. The manual tests are, as the name suggests, carried out by persons using a range of tools for specified periods of time according to the particular target grade.
To provide for CE marking, European Standards prEN1627 ~ 1630 have been published. The proposed European Standards follow the same principles as defined by reference to the LPS1175 range of tests with six grades of performance defined by reference to Table C.1 of prEN 1627 : 2006.
The ‘Secured by Design’ programme makes reference to PAS24. This is identified as a ‘Low Risk’ performance designed - to resist an opportunist attack. PAS24 test details are published by British Standards and are in effect a ‘client specification’ by reference to Local Authorities planning requirements, to provide for a level of security for single leaf entrance doors for residential buildings. The PAS24 test is supported by ACPO (Association of Chief Police Officers) as part of the Secure by Design initiative. In terms of grading, the performance falls somewhere between LPS1175SR1 and LPS1175SR2 and is between Classes 1 and 2 by reference to the proposed European standards.
Since its introduction, there have been about five amendments to the PAS24 test. This does not necessarily reflect a deficiency in the test methods employed but rather a feature that is perhaps unique to doorsets required to provide for a security performance. The ‘villain’ constantly finds new and innovative methods for breaching security and PAS24 needs to be constantly amended to react to new threats. As it is, it may be some months and perhaps longer before the test method can be adequately amended to meet a new threat, in the meantime doorsets tested to previous versions of the standard remain vulnerable to the new method of attack. When considering European standards, the methods for seeking amendment to an established standard requires the involvement of a lengthy and bureaucratic process that is currently far too slow a process to provide for the rapid reactions necessary to address problems of this nature. There is also an obligation upon governments in particular to accept CE marking as evidence of satisfaction of performance requirements. This consideration forms part of the UK objection to the introduction of the EN1627 ~ 1630 standards.
The causes for concern with regard to the introduction of EN1627 ~ 1630 relate primarily to the manual intervention tests i.e. EN1630:
• To have credibility as a CE marked product, it should be possible to repeat a test result in any laboratory that is approved for such testing within the tolerance limits applicable to the test. It is unclear how the physical characteristics and / or the state of mind of the attacker could be controlled to provide for such a uniformity of result.
• For EN1627 Grades 1 ~ 3, the objective is to resist a casual or opportunist attack. Laboratory staff carrying out such attacks are likely to learn how to breach the security of a particular design as a consequence of testing experience. It is unclear as to what point an attack that is intended to represent an ‘opportunist’ attack effectively becomes a ‘professional’ attack as a consequence of the learning experience, or how such considerations could reasonably be addressed.
The considerations identified above also apply to PAS24 and other tests that include a manual intervention element. However, it is suggested that it is easier to address such concerns on a local (national) basis rather than by recourse to the lengthy and bureaucratic processes necessary to address such issues in respect of European standards.
A further concern with regard to the European standards in general, and to EN1627 in particular, is the extent to which extraordinary and seemingly unnecessary powers are being provided to the testing laboratories following the introduction of the CPD (Construction Products Directive). This is illustrated by reference to Annex D of EN1627 and in particular the first line of Annex D.3 which requires an ‘expert statement written by the testing laboratory’ in respect of modifications to a tested product. It is suggested that the role of the testing laboratories is to competently test products to the standards required by the sponsor. It is not necessary for the test laboratory to have detailed knowledge of constructions or how a particular result was achieved. Any unnecessary publication of information related to security products in particular (perhaps even the publication of test methods) is, in itself, a breach of security. It is likely that the best person to determine what might or might not be a suitable variant to a tested product is the designer of a successful product.
There are two basic forms of attack that may be anticipated in respect of security doorsets:
1/ Brute force physical attack
2/ Manipulative attack.
All too frequently we see on our televisions police raids being carried out in connection with drugs or for other reasons. Speed and surprise are an important element in connection with such raids and the form of attack usually employs brute force using a steel battering ram carefully aimed at a known vulnerable part of a doorset. This method of entry is an example of the ‘brute force’ or physical attack.
Anyone who has ever lost their house keys may have needed to contact a locksmith to assist with entry. Those who have experienced such misfortune may identify with the scenario that the time for attendance in such an emergency often seems excessive but, that entry is gained often within seconds of the locksmith’s arrival usually at a considerable cost in consideration of the skill and knowledge that was applied rather than, for the time of the attendance. The method of entry is generally guarded but is usually achieved by the use of manipulative methods.
Elements that can influence security in connection with doorsets are many and various. The testing of security doors relates to the complete doorset as installed, rather than individual components. Considerations related to security doorsets might include:
Perception: An opportunist attack will generally be concentrated on perceived weaknesses identified by way of visible examination. If a door looks solid and secure then that in itself may act as a deterrent.
Direction of Opening: The direction of opening of the door can have an influence on security doorset designs. If a door opens into the secure area then the gaps between the door and the frame are effectively protected by the frame doorstop on the closing face. This may however create an increased risk at the strike plate position(s) in the event of a physical attack. If the door opens out from the secured area the operating gaps that are necessary between the door and the frame can provide for a point of access for the use of jemmies or other lever devices.
Glazed Apertures: Glass and glazing may be identified as a potential weakness. The PAS24 test specifically excludes attacks on glazing as do other EN1627 ~ 1630 tests. In practice laminated glass using polymer interlayers provide for excellent impact resistance. These glass types are available in varying thicknesses. However, the performance of the glazed aperture is also dependent upon the method of securing the glass into the door. The beading system and method of fixing is an important consideration.
Locks: It is important to have a good quality security lock. Some large robust looking locking devices might be suitable for use with (say) steel doors but could actually create a weakness if used with wood doors of a similar thickness. Multipoint locks using a main unit with one or more ‘slave’ units operated from a single keying point to provide for a means for the door to be secured to the frame at a number of points.
NOTE: Multiple performances (e.g. fire and security) required for a single location should be avoided if possible to prevent the satisfaction of one performance undermining the other performance. The use of multipoint locking systems can adversely affect fire resistant performances.
The use of multiple separate lock cases can provide for improved security relative to a multipoint locking unit particularly if different keying systems are used. The old 5 lever security deadlock still has a lot going for it in security terms. The downside to this option is that additional keys have to be carried and it is more time consuming and inconvenient when securing the door when leaving the building and unlocking using two or more keys when re-entering the building.
Numerous mechanical and electrical numerical keypad operated locking systems are available together with electrically operated locks or strike plates, some of these can be linked to burglar alarm systems.
Locks are likely to be the primary target for manipulative attacks and the lockcase area of a door is likely to be a target for a physical attack. Where the door operating gaps are not protected by the doorstop, i.e. where the attack is applied to the opening face of the door, astragals can be added to provide cover at the closing stiles to minimise the risk of jemmy attack at the closing stiles of a door.
Where the attack is applied to the closing face of the door there is the risk that the strike plate or the lock case can be forced out of position by way of physical attack. When used with steel frames, a box type frame fixed keep plate can be used to provide improved security but the box type keep can create a weakness if used with wood frames. Other strike plate designs with angled fixings can be more suitable for use with wood frames.
The lockcase size may be of lesser importance if used with steel doors but a large lockcase can create a weakness if used with a wood door.
For wood doors in particular it is generally helpful to clamp the faces at the lock position. Some lever handle designs include bolt through fixing backplates that provide for the desired clamping action. Alternatively separate bolt through metal plates can be used at the lock positions.
Hinges: For doorsets that are designed to resist attack on the closing face of the door, the frame doorstop will cover any gap between the door leaf and the frame.
Where the attack is applied to the opening face of the door there will be gaps between the butt hinge positions that can be exploited by use of jemmies. Attacks have been carried out by milling off the knuckles of the hinges (a surprisingly quick activity) this allows for the door to be opened from the hinge side.
Security hinge pins can be used with these being available as separate units or as part of the hinge design. Effectively the security pins lock the door into the frame at a number of positions when the door is in the closed position. Thus, even if the hinge knuckles are removed it is still not possible to open the door from the hinge side without the need for a considerable amount of additional work.
Continuous full door height hinges can be used to deny access to the operating gap at the hinged stiles of the door. Hinges of this type effectively fill the operating gap to the full height of the door leaf at the hanging stile to prevent jemmy access. Whereas it would still be possible to mill off the hinge knuckle this would be a difficult and time consuming task for a full door height hinge. As with butt hinges, continuous hinges can be fitted with hinge security pins. By way of example, the PemkoHingeTM is a continuous geared aluminium hinge that is available with dedicated security hinge pins. This particular hinge design is also available with dedicated (and concealed) magnetic sensors and electrical connection modules for linking to security / alarm systems.
Letter Plates: Anything that penetrates through the thickness of the door leaf provides a potential path for undermining the security of a doorset. Such access either through operating gaps or letter plates may provide a route for manipulative attacks. Whereas security grade letter plates are available, an alternative is to consider separate provision for the depositing of mail.
Threshold Gaps: Any gap that passes though the thickness of the door provides a potential route for attack. In addition to providing a weak point that may be exploited by an intruder, threshold gaps may also offer a convenient access route for insects and vermin. Whereas the frame doorstop provides for a security function at the head and stile positions, there is often no doorstop provision at the threshold. Pemko is perhaps better known for its automatic door bottoms when used for sound attenuating or smoke sealing purposes, but variants of the Pemko automatic door bottoms are available with solid inserts that restrict access in this vulnerable area. Pemko also provides a range of stepped thresholds that meet BS8300 (Building Regulations [England & Wales] - Approved Document ‘M’) requirements in respect of provisions for the disabled. Additionally, Pemko low level saddles can be used with separate steel threshold doorstops that can be securely anchored into flooring.
It should be appreciated that it is the doorset as a whole that is required to provide for the security performance. Whereas components as identified above can often enhance security performances, advice should be sought before selecting and using such products. Anything that is added to or removed from a security doorset of a proven design may undermine the basic elements that provided the security performance.
The perception, correct or otherwise, is that crime is on the increase and it is likely that there will be an increasing demand for robust security products, including security doorsets. As is demonstrated by reference to experiences associated with PAS24, there is an ever changing demand as villains discover new and innovative methods for breaching security. Installed doorsets of designs that might have previously met PAS24 performance requirements would not achieve the same result if tested today due to changes to the test methods.
The Secured by Design initiative is welcomed as a necessary response to crime but perhaps consideration could be given to extending the scope of the concept to provide for suitable upgrades to existing installations. In the case of dwellings this could perhaps be achieved by use of contacts between crime prevention officers and Local Authorities or by way of communication within the scope of Neighbourhood Watch schemes.
If manual intervention tests are left to the sole discretion of the test laboratories then, as a matter of course, laboratory technicians will learn from previous experience, this experience is likely to be applied to later testing. This could result in unreasonable testing, particularly where ‘professional’ experience is applied to a product that is intended to resist an ‘opportunist’ attack. This could be grossly unfair on manufacturers and provide a disincentive to invest in the development of such products.
Conversely, if the manual intervention tests were carried out solely at the discretion of a manufacturer, there might be concerns in connection with a possible inclination to employ persons of limited physical ability to carry out the tests to achieve desirable results. The test results might be favourable but would attacks carried out by a team of 90 year old grannies in wheelchairs be representative of the attacks that the products are intended to resist?
It is difficult to see how any meaningful testing of security doorsets could be carried out without the benefit of manual intervention tests but, these should to be representative of the particular type or method of attack anticipated by the client authorities. Perhaps the supervision of the manual attacks should be provided by the client authorities?
The method of attack can be a variable even with possible differences with regard to preferred methods of attack on a regional basis. As the methods of attack can change without notice, there needs to be a ‘fast track’ provision for changing test methods to react quickly to new and innovative methods of attack and where possible, for providing the opportunity for security upgrades to existing installations.
The development of security doorsets can be an expensive exercise and manufacturers who invest in such products will need to know that they can recover the cost of their investment. Whereas it is possible to calibrate measuring equipment for the purpose of carrying out static and dynamic testing and therefore to design suitable products to meet these requirements, it is not possible to ‘calibrate’ persons employed to carry out manual intervention tests thus making it more difficult, if not impossible, to determine cost effective designs to meet the performance requirement for any particular defined grade or performance class. On the other hand, there is an increasing demand for effective security products including security doorsets. It is questionable as to whether or not this is a suitable performance sector for consideration by reference to European test standards for CE marking purposes. | |
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