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Access control in and around buildings is concerned with allowing the free flow of authorised people while denying access to unauthorised visitors. This includes the control and management of vehicles as well as pedestrian flow.

Requirements range from simple remote systems for perimeter doors to a sectorised installation with flexible access privileges and usage records. Sensitive areas may need special protection and access may be required by different people to different areas at different times. It may also be important to monitor and have a record of who went where and when.

It is essential that these issues are thought about in the early stages of the project to ensure they are fully integrated into the overall M&E services design. This is particularly pertinent in buildings where security is an important factor, such as airports and banks.

The benefits of an effective, robust access control system include:

• The generation of valuable management information. Knowledge of people鈥檚 movements can help planning to achieve greater efficiencies.
• Securing certain areas of a building, where appropriate.
• Protection of employees, visitors, property and sensitive information.
• Integration with other security systems within the building, to enhance the overall level of protection.
• Assistance with car park management.
• Help in satisfying the requirements of the Disability Discrimination Act.
• Controlling access to other facilities or equipment, such as vending machines or computers.

This article is a brief overview of the typical issues that need to be considered when formulating an access control strategy for a new development.

Vehicle management

The sophistication and cost of vehicle management systems vary according to the number of cars to be controlled, whether a fee is charged, the type and number of entrances and the level of security required. For instance, retail and airport environments may have very different needs from commercial office buildings.

The typical elements of a vehicle management system are:

Barriers

The most common means of managing vehicular flow is by using traffic barriers, an often overlooked but vital part of any car park management system. Groundworks are frequently completed before anyone thinks about the barrier system, which adds cost and time to the installation.

Barriers can be electro-mechanical or hydraulic. The latter offer a longer life and are robust and reliable. The former are cost-effective to buy but more expensive to operate. For sites with high traffic volumes, it is worth considering barriers with built-in loop detectors and fast cycle times.

Barriers can be linked to access control or traffic counting systems. They can also be automated using a tagging system on the cars of office staff.

Rising bollards

Rising bollards provide a more substantial barrier for controlling access and urban traffic and protecting sensitive areas with minimal visual intrusion. They can be manually, electrically or pneumatically operated and controlled to rise and fall on impulse from a transmitter or access control system. They can also be key operated.

Parking management systems

The most common system for fee-paying car parking is time based. The system uses magnetic strip cards to hold access rights and validity-time data and has an entry station, pay machines and an exit station. From the information stored on the card, the system validates entry time, calculates the fee and issues the card for exit. Cards are captured for reissue and all transactions can be logged for instant verification and later report generation.

Pedestrian access management

The key considerations when formulating a pedestrian access control strategy are:

• location and number of sites
• number of areas and points to be controlled
• layout of building
• number and turnover of occupants
• number and access required internally for visitors
• disabled access requirements
• how the system is to be managed internally
• future growth
• level of security required incorporation of other functions such as cashless vending.

The range of options available to manage the access and movement of people in and around buildings is summarised briefly below. The level of sophistication and security will depend on assessment of the factors above.

Coded entry systems

This is simply where a standard four-digit code is set to allow certain staff access through a particular door or doors. There is a keypad outside the door with a power supply and electric lock on the secure side of the door. Battery back-up should be provided in the event of a power failure.

This can also form part of a door intercom system.

Door intercom systems

These are now considered essential for any small to medium-size office in the UK. Audio systems consist of an intercom panel at the entrance connected to a door phone in the office and an electric lock.

Video systems may be considered more appropriate, which means the addition of a camera in the entrance panel (with infra-red lighting to improve image resolution) and a monitor on the receiving unit.

Turnstiles

Controlling access through the main entrances of a building is fundamental to providing a secure environment. Even with access control on a door it is possible for somebody to 鈥渢ailgate鈥�, thereby undermining the security system.

Greater security and control can be achieved by installing turnstile access at the main entry points of a building. There are mid-height, full-height or monitored versions. Factors to consider in the choice of the most appropriate type include:

• The number of people using the building. One lane is enough for 150 to 200 people, assuming the turnstiles are set up to be bi-directional.
• Are they required to fail to an open position on a fire alarm activation?
• Means of activation (normally card).
• Requirement to be alerted if tailgating takes place. Some of the systems offer this feature and can provide an impulse to a local alarm, CCTV camera etc.
• Is an override to the system with a remote push button required?

Automatic doors 鈥� card access

Reader technologies provide the interface with the access control system and vary considerably. Swipe and access cards are capable of allowing or disallowing access to specific areas depending on the level of access required/authorised.

Swipe cards, although regarded by many as old-fashioned, rely on a low-cost basic technology which has proved over the years to be very effective. 星空传媒 users carry a small card which, when swiped through the reader, allows them in if the card is valid for that day and time.

Where high user populations are likely, this can be an economical option as the cost of the cards is low. The system can be specified for buildings with many card readers, linked back to a PC, thus allowing individual cards to be timed and controlled and providing a full audit trail of who went where and when.<