Except in a relatively few instances, building security has traditionally received little consideration during the design stage.
However, today we face a new set of challenges associated with security threats. Crimes against businesses and increasing threats of violence, terrorist attacks, bombings, and shootouts that have resulted in tens of billions of dollars of costs annually have in creased interest in building security significantly. Airport security has increased in an attempt to prevent future acts of terrorism and, for the most part, to limit what can be taken on an aircraft and potentially used as a weapon. The utility and chemical industries have implemented extra security procedures to provide better protection and help prevent contamination and loss of power. Most industries have taken additional steps to strengthen themselves against potential terrorist/criminal actions.
A building security system can be thought of as a life safety system. It can assist in the safety of building occupant and business personnel because it minimizes prohibited entry by unauthorized persons such as disgruntled former employees, terrorists, or common criminals. It also prevents damage that can result in building occupant injuries.
Building security must be approached in building design, selection of materials used in the building, occupant control, and surveillance and alarm systems.
Initial Building Design
Security issues in a building should be considered in the early planning and architectural design stages. This will simplify the ensuing security system design, decrease security costs, and re duce the potential for crimes to occur in the building or building complex. All aspects of the design should be considered including access routes, landscaping, signage, lighting, materials, colors, entryways, and interior layouts.
Designers of a building should pay particular attention to the locations of doors, windows, loading docks, and money handling rooms. These areas should all be easy to view from other surrounding areas and be well lit (as should elevators and stairways). Ledges and exterior ornamentation that might allow people to climb up the side of the building should be avoided.
One of the best investments in terms of security is the provision of high levels of illumination throughout the project.
Material Selection
Doors, windows, and their hardware should be carefully selected to be certain that they will discourage intrusion. Windows should be designed so that the glass cannot be removed from the outside, and the hardware should be such that the window cannot be opened from the outside with a plastic card or wire. Doors in question should be metal, and locks should be selected so they cannot be opened with a credit card. Also be certain that the door's hinge pins cannot be taken out from the outside of the building and the door removed.
Many building codes require that all doors that lead into stairways and exits be operable from both directions in case of fire or emergency. When such a door is not to be used except in an emergency, it should be wired to an alarm system that activates when the door is opened; large signs should be placed on such doors warning of the alarm system setup.
Buildings that are more prone to security problems be cause of the location or the type of occupancy should be built of materials that prevent easy entrance. For example, exterior wood frame walls are much easier to "open up" than cast-in place concrete, CMU, or brick walls. The roof assembly should also be carefully selected. It is easier to cut or pry an opening in a plywood roof than a concrete or gypsum roof. Roof scuttles (hatches), stair access, ventilation openings, and other equipment on the roof should also be carefully chosen.
Building Security Systems
For most projects, an electromechanical security system pro vides economical and effective security. Such systems have been used extensively in residences and in commercial, industrial, and institutional buildings.
A basic electronic security system consists of a control panel, keypad, digital communicator, backup battery, trans former, sensing devices, and a horn, buzzer, or siren. Various sensing devices such as door/window contacts, motion detectors, glass break sensors, smoke detectors, heat sensors, temperature sensors, carbon monoxide sensors, flood/water sensors, panic/hold-up buttons, and medical panic pendents are used, depending upon the size and complexity of the installation. The system might also use closed circuit television cam eras and monitors.
img. 29 An indoor camera used for remote surveillance via a local area
network or the Internet. ( --) img. 30 A remotely controlled closed circuit
television (CCTV) video surveillance camera. ( --) The setup of an electronic
security system is quite simple, especially when it is installed in new
construction. In the simplest system, an electric circuit to all the
doors and windows selected and to the alarm connects to the monitoring
system. Once the sys tem is programmed, if the circuit is broken at any
of the contact points (at a door or window), the alarm goes off. There
are many types of installations and equipment available, depending on
the equipment manufacturer and the desired security.
Perimeter Protection --- The first level of protection for any security system is perimeter protection. Perimeter protection includes such areas as doors and windows. It may also include closed circuit TV video surveillance (discussed later).
Alarm contacts, either the plunger or the magnetic type, can be installed on doors and windows to protect against unauthorized entry. The plunger-type contact is installed so that when the door or window is closed, a plunger is pushed in, and when the door or window is opened, the plunger pushes out, setting off the alarm.
The magnetic-type contact consists of two contacts that are surface mounted, so that when the door or window is closed they make contact with each other, and when the door or window is opened the magnets are separated, setting off the alarm.
Interior Protection---Interior protection provides a backup to perimeter protection.
This includes:
• Infrared (IR) motion detectors pick up body heat from any living being within the protected areas. IR detectors can be strategically placed inside a space to pro vide this kind of protection. In homes, pet immune motion detectors will allow a large animal to move past them without activating the alarm.
• Glass break detectors are digital microphones that have a range of up to 25 ft (8 m) and can recognize the sound associated with breaking glass. Glass break detectors can be installed near any window or pane of glass that can be broken by forced entry.
• Floor mat detectors will activate the alarm if stepped on. Common concealed locations for the floor mat entry detector include under the rugs, inside all exterior doors, and just below windows.
• Emergency immediate-response keys and pendents are used to summon aid in an emergency. When pressed for 2 s, the emergency key or pendent will send an alarm to the central monitoring station for immediate notification of the proper authorities.
Video and Audio Surveillance --- Closed circuit television (CCTV) video surveillance systems can allow a small number of security staff to monitor indoor areas of a building and the building site. A few basic applications include loading docks, parking areas, areas of high shoplifting potential, schools, casinos, and banking institutions.
Surveillance cameras serve as a way to monitor events and to provide a deterrent. On remote control surveillance cameras, pan, tilt, and zoom capabilities can be controlled from a central location. The signal is transmitted through a local area network or via the Internet. Examples are shown in img.s -29 and -30. The most effective surveillance systems are those that use others monitoring devices such as motion sensors and audible alarms to notify personnel when a problem occurs.
Surveillance systems can record activities. Recorder play back functions can be used to review a past incident and assist police in catching the perpetrators of a crime. Digital video recording (DVR) equipment stores data that can be digitally enhanced and analyzed.
img. 29 An indoor camera used for remote surveillance via a local area
network or the Internet.
img. 30 A remotely controlled closed circuit
television (CCTV) video surveillance camera.
Control Panels and Centers
In residential installations, the control panel used to activate and deactivate a detector circuit is powered by the regular household power (120 V) available, with a stand-by battery power source to take over in case of a power failure. Many of the units have lights that indicate when the circuit is on. In addition, they may have a test alarm button so that the entire sys tem can be tested.
To allow the occupant to leave and re-enter without sounding the alarm, an exit/entry control panel is installed. It includes an outside key-operated switch and an inside switch at the door. This type of control panel will sound the alarm if any attempt is made to disconnect the outside wall plate. Indicator lights on the wall plate turn on when the system is activated. Some exterior control panels are simply activated and de-activated by an outside key-operated switch, with none of the protective features mentioned.
When the outside control panel is used, a push-button interior alarm switch is installed. One inside alarm switch may be in stalled for the entire system, or several may be installed to operate individual doors and windows. The latter allows the opening of a door or window without having to de-activate the entire system.
Also available is a control panel with a time-delay exit and entry feature. This control delays the operation of the sys tem, allowing the occupant to leave or re-enter the building without setting off the alarm. With this control panel, an outside key-operated switch is necessary. Control panels should be mounted where they will be readily accessible to the adult occupants but not to any children or visitors (e.g., in a closet, laundry area, bookcase, or cabinet).
In commercial installations, a main control panel per forms more complex functions. It consists of a keypad, video console, backup battery, and transformer. Remote sensing de vices are connected to the main panel. The system typically includes CCTV cameras and monitors. On large installations, remote control panels are tactically positioned at outlying locations. The main control panel and remote control panels are connected so they can communicate with one another.
Alarms
The alarm set off by the various systems may be a bell inside and/or outside the building, a bell inside and a horn outside, a horn inside and/or outside, or a horn with a light (beacon). In many locales, the alarm system can be connected directly to the fire or police station. When available, this is the best arrangement.
Generally, the next best arrangement is to have an inside bell or horn with an exterior horn and a light. The more noise the systems make, the more likely it is that neighbors will hear it and call police-and the more likely it is that whoever breaks in will leave without taking anything. To be effective, this type of system must depend on the cooperation of neighbors, so be certain that they understand what the alarm means and that they should call the police to report any attempted break-in.
More elaborate electronic security systems utilizing ultrasonic sound, photoelectric and microwave devices, audio activated devices, and closed-circuit television are also available.
Many of the systems are used in combination to achieve maxi mum control. Often, the integrated system is set up with a number of alarms that may warn of smoke, fire, and intruders.
Obviously, the larger the building complex is, the more money should be available for security systems.
Electronic Access Control Systems
Many large companies use electronic access control systems to control employee entrance by identifying an authorized individual and allowing that person access to a restricted area. Access control can deny an unauthorized employee or outsider access into a restricted building or space. It also allows management to increase employee productivity by preventing unrestricted traffic to different areas of the building. It can also track employee movement through a building or room. The owner can recall this information at a later time as the system can store this information in a database.
A commonly used access control method requires insertion of a coded electronic cardkey (similar to an encoded credit card) into a wall-mounted receptacle that decodes the key and activates the door lock only for the proper key. This type of lock is much more secure than the standard cylinder lock used on most doors. A wall or door mounted keypad can also allow the employee access after the individual has properly entered the keypad code. These control devices can operate independently or be connected to a central control panel. Codes can be updated or changed regularly to purge access for former employees.
Another control method known as photo identification requires the employee to punch a coded number on a keyboard.
Within seconds, a picture of the person who is assigned that code is flashed on the screen for the guard to check. It operates by the same principle as the instant replay technique used on television and uses the same equipment.
Biometric identification, the latest technology, is the automatic assessment and recognition of a unique body feature (e.g., fingerprint, eye and face recognition) or personal action (e.g., voice recognition). With biometric identification, a per son may place a hand on a hand plate; the device then measures such things as finger size, fingertip angle, and skin translucency, and compares this information either with an identification card that is magnetically coated or with information that has been placed in the memory of the computer.
Security Personnel
Security guards are personnel that provide security in many buildings by serving as a physical presence that tends to deter crime and improper activities. Guards are positioned at strategic points in the facility so they have an overlapping view to monitor activities. They might sit at a control desk near the main entrance to the building and monitor or control access.
The central console of surveillance equipment might be used to assist the guard in monitoring events. Guards might also be used for occupant or vehicular traffic control in emergency situations.
In most instances, the training level and competency of a security guard should not be compared with that of a police man. Most security guards do not have the training that police men receive. Many guards hired range from those too inexperienced to do the job properly (e.g., college students who do homework on the job) to those who are not physically capable of handling the job (e.g., some semiretired personnel).
Security guard jobs are generally low paying. One survey has shown over a third of those guards interviewed indicated that the guard job was the best job available to them and that they had been unemployed before they took the guard job. It is unfortunate that those persons hired to protect the building and materials are frequently the lowest paid personnel in many companies, perhaps making them more susceptible to stealing or taking bribes.
Neither guards nor electronic devices by themselves are the complete answer to building security. The selective use of electronics, tied into central control points, reduces the need for security guards. Using this approach, adequate money should be available to hire and train qualified guards.
img. 31 An emergency generator. ( --)
img. 32 An automatic transfer switch for an emergency generator system. ( --)
Emergency Power Systems
Lengthy or recurring power outages are an inconvenience be cause lighting, space heating, and air conditioning and alarm systems no longer operate. In the business world, computers, office machines, and Universal Product Code (UPC) scanners do not function, which will result in financial loss. In the health care industry, power outages can result in loss of life.
Emergency power is electricity that is generated locally on a limited basis for the purpose of supplying electricity to critical devices during a general power outage. Emergency power can be provided by a backup battery system or emergency stand-by generator system. Typically only small devices such as emergency lighting and alarm and communication panels operate on battery backup systems.
Emergency power systems consist of two major parts: a generator that produces electricity and an engine that drives the generator. The generator can be switched on manually or automatically.
Generator engines can be powered by gasoline, diesel fuel, liquid petroleum gas (propane), or natural gas. Selection of a fuel is related to availability of the fuel in a power outage (e.g., natural gas versus diesel fuel). Effective storage of gasoline and diesel fuels requires a storage tank and the periodic addition of a chemical stabilizer. Propane requires a storage tank, either above or below ground. Natural gas is delivered by pipeline and may not be available in some emergencies (e.g., earthquake). The decision to select a gas or fuel is based on whether a particular fuel type is already being stored or used on site for another use. Concerns with engine noise dictate the location of the generator.
On large systems, an automatic transfer switch (ATS) monitors utility power from the utility line. When utility power fails, the backup system will start within 15 to 30 s and automatically transfers to generator power. Once utility power returns, the ATS monitors that the power is stable and transfers back to utility power when it is acceptable.
Emergency generators are designed to produce either single- or three-phase power. Three-phase generators produce 120/208 or 277/480 V and single-phase generators are 120 or 120/240 V. One manufacturer makes generators available in 12, 17, 25, 40, 50, 55, 60, 75, and 100 kW capacities. Smaller systems are available for residential installations. Examples of an emergency generator and an automatic transfer switch for an emergency generator system are shown in imgs -31 and -32.
Emergency Lighting
Emergency lights enable building occupants to safely escape the building in the event of a power failure. Equipped with backup batteries, these lights are capable of powering exit and emergency lights for more than an hour. Emergency lighting is a critical element of a safety system in the event of a power failure. Emergency illumination is typically required in all buildings where the exiting system serves an occupant load of 100 or more. (See img. 33.)
img. 33 Emergency lighting with a remote battery backup for power outages. (
--)
Emergency Action Planning
Emergencies and other threats to life and property can be caused by both human-made and natural events (e.g., fire, hurricanes, tornadoes, blizzards, floods, earthquakes, tsunamis, toxic chemical and nuclear releases, explosions, bomb threats, acts of terrorism, and so on). They can occur rapidly and with out warning. Emergency plans and procedures must be established to protect building occupants and employees from serious injury or loss of life and property from further damage in the event of an actual or potential major disaster.
A building emergency action (BEA) plan provides for immediate, positive, and orderly action to safeguard life and property in the event of any emergency or disaster (except enemy attack). The BEA plan should address emergencies that the employer may reasonably expect in the workplace. It establish policies, procedures, and an organizational structure for response to emergencies and identifies the roles played by various personnel.
An emergency management team is formed to address ongoing emergency planning and coordination efforts, including issues regarding road closings, access to buildings, emergency evacuation procedures, providing updated security information to employees, and so forth. This team formulates the BEA plan. During an emergency, the designated leader of this team puts into service immediate actions and ensures that response efforts are coordinated with the various groups responsible for public and employee safety. This team directs emergency actions from the emergency operations center, a designated central communication room. An incident response team with medical, firefighting, and/or hazardous material handling personnel tend to the incident and report back to the emergency operations center, where the emergency management team takes further action, if necessary.
A building evacuation plan is a central part of the BEA plan that ensures orderly evacuation of building occupants by establishing emergency escape procedures and escape route assignments. A decision to evacuate is made by the designated leader of the emergency management team based typically on the worst-case scenario of the incident. Consideration for evacuation is given to the specific threat (e.g., fire, bomb threat, explosion, hazardous material incident, and so on), its extenuating circum stances (e.g., time of day, likelihood of further damage, and so forth), and the recommendation of local governmental officials.
Typically, every building or building area (in large buildings) has an evacuation team to assist in emergency evacuations. Members of the team include floor monitors and stairway monitors, who act in response to the specific emergency and coordinate safe evacuation. Floor monitors check rooms and other enclosed spaces for occupants who may be trapped or otherwise unable to evacuate the area. Stairway monitors direct occupant egress on stairways. Monitors (and fellow employees) also assist handicapped occupants who may need extra assistance. Once evacuation is accomplished, the monitors verify that all employees are in the safe areas. Normally, one monitor for every 20 occupants provides sufficient supervision.
At the time of an emergency, monitors and other employees should know what type of evacuation is necessary and what their role is in carrying out the plan. In cases where there is a serious emergency inside the building (e.g., uncontrolled fire, indoor toxic chemical and nuclear release, explosion, bomb threat, and so on), total and immediate evacuation of all occupants may be necessary. In some cases, only those employees in the immediate area of the emergency are directed to evacuate or move to a safe area. In other cases, it may be necessary to direct occupants to a safer area of the building (e.g., tornado, hurricane, outdoor toxic chemical and nuclear releases, acts of terrorism, and so forth).
In some emergencies, an evacuation of nonessential occupants with a delayed evacuation of others may be needed for continued operation of building operations. Essential personnel are employees who have been se1ected in advance to remain behind to care for essential operations. They perform these tasks until evacuation becomes absolutely necessary. Essential operations may include monitoring of power supplies, water supplies, and other essential services that cannot be shut down for every minor emergency. Essential operations may also include tending to chemical or manufacturing processes that must be shut down in stages or where specific employees must be present to assure that safe shut down procedures are accomplished (e.g., shut down of a nuclear plant).
The use of emergency floor plans that clearly show emergency escape routes should be included in the BEA plan. These floor plans and signage should be displayed in corridors and stairways of the building to educate and guide building occupants. The designation of refuge or safe areas for evacuation should be determined in advance and identified in the emergency floor plan. In a building that is compartmentalized into fire zones, the refuge area may be within the same building but in a different zone from where the incident occurs. Exterior refuge or safe areas include parking lots, open fields, or streets that are located away from the site of the emergency and that provide sufficient space to accommodate occupants. Occupants should be instructed to move away from the exit doors of the building, and to avoid congregating close to the building, where they may hinder emergency operations.
Before implementing the BEA plan and on a re-occurring basis, a sufficient number of personnel to assist in safe and orderly emergency evacuation of occupants (e.g., employees, visitors, and so on) should be designated and trained. This training generally involves a review of the BEA plan, technical training in equipment use for emergency responders, and evacuation drills. In large facilities (e.g., manufacturing plants, hospitals, airports, and so forth), full-scale training exercises should take place regularly. Essentially, employees must know what is expected of them in a potential emergency situation to ensure their safety from fire or some other emergency.
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