Publication Date: 5/1/80
    Pages: 16
    Date Entered: 2/23/84
    Title: PERIMETER INTRUSION ALARM SYSTEMS (1/75) (REVISION 1, 6/76)
    Revision 2
    May 1980
    U.S. NUCLEAR REGULATORY COMMISSION
    REGULATORY GUIDE
    OFFICE OF STANDARDS DEVELOPMENT
    REGULATORY GUIDE 5.44
    (Task SG 479-4) PERIMETER INTRUSION ALARM SYSTEMS
A. INTRODUCTION
    (*) Part 73, "Physical Protection of Plants and Materials," of
    Title 10, Code of Federal Regulations, specifies performance
    requirements for the physical protection of special nuclear materials
    and associated facilities. Section 73.20 describes the general
    performance objective and requirements that must be met through the
    establishment of a physical protection system. Performance capabilities
    necessary to meet the requirements of Section 73.20 are described in
    Section 73.45. Paragraph 73.45(c) requires that only authorized
    activities and conditions be permitted within protected areas, material
    access areas, and vital areas through the use of detection and
    surveillance subsystems and procedures to detect, assess, and
    communicate any unauthorized access or penetrations or such attempts by
    persons, vehicles, or materials. Furthermore, Section 73.46 outlines
    typical specific safeguards measures that will often be included in an
    overall system that meets the requirements of Sections 73.20 and 73.45.
    The use of an intrusion alarm subsystem with the capability to detect
    penetration through the isolation zone is specifically called out in
    paragraph 73.46(e)(1). For power reactors, paragraph 73.55(c)(4)
    requires that detection of penetration or attempted penetration of the
    protected area or the isolation zone adjacent to the protected area
    barrier ensure that adequate response by the security organization can
    be initiated.
    This guide describes six types of perimeter intrusion alarm
    systems and sets forth criteria for their performance and use as a means
    acceptable to the NRC staff for meeting specified portions of the
    Commission's regulations. It also references a document (SAND 76-0554)
    that provides additional information in this area, especially on the
    subject of combining sensors to yield a better overall performance.
    ----------
    (*) Lines indicate substantive changes from Revision 1.
    ----------
B. DISCUSSION
    Perimeter intrusion alarm systems can be used to detect intrusion
    into or through the isolation zone at the perimeter of the protected
    area. A system generally consists of one or more sensors, electronic
    processing equipment, a power supply, signal lines, and an alarm
    monitor. Detection of an intruder is accomplished by the alarm system
    responding to some change in its operating condition caused by the
    intruder, e.g., interruption of a transmitted infrared or microwave beam
    or stress exerted on a piezoelectric crystal. The choice of a perimeter
    alarm system is influenced by considerations of terrain and climate. At
    present, no single perimeter intrusion alarm system is capable of
    operating effectively in all varieties of environment.
    The mode of installation of the perimeter alarm system influences
    its effectiveness. In general, dividing the site perimeter into
    segments that are independently alarmed and uniquely monitored assists
    the security organization responding to an alarm by localizing the area
    in which the alarm initiated. Segmenting of the perimeter alarm system
    also allows testing and maintenance of a portion of the system while
    maintaining the remainder of the perimeter under monitoring. It is
    generally desirable that the individual segments be limited to a length
    that allows observation of the entire segment by an individual standing
    at one end of the segment.
    Effective use of a perimeter intrusion alarm system is facilitated
    by a regular program of system testing. Operability testing can be
    performed by a guard or watchman penetrating the segment protected by
    the alarm system during routine patrols. Performance testing, i.e.,
    manufacturer's specification testing and detection probability testing,
    however, is usually more elaborate. In any case, testing can be
    conducted without compromising security only if performed under
    controlled circumstances such as direct visual observation or by
    closed-circuit television of the area being tested while a specified
    test is conducted.
    To ensure secure operation, the system may periodically monitor the
    sensor transducer and signal processing circuits. This self-checking
    feature can vary depending on the type and design of the alarm system.
    Many systems require self-excitation of the sensor transducer (e.g.,
    vibration, strain, pressure) while others monitor the signal level at
    the receiving transducer (e.g., microwave, infrared). However, several
    worthwhile commercially available perimeter alarm systems provide little
    or no self-checking circuitry. To ensure normal operation for those
    alarm systems that do not incorporate self-checking circuitry, the
    licensee should institute a test program that will periodically test
    each segment of a perimeter alarm system to verify that it maintains the
    proper sensitivity to detection.
    In order to increase the probability of detection and lower the
    false alarm rates, a combination of sensors may be desirable in certain
    environments. Additional factors to be considered in the selection and
    application of single sensors or a combination of sensors are presented
    in a Sandia Laboratories report prepared for the Department of Energy
    entitled "Intrusion Detection Systems Handbook" (IDSH), SAND 76-0554,
    and in particular Sections 8.3 and 3.2. Additional information in this
    area, i.e., integrated perimeter systems, is scheduled for development
    by the NRC. An important element of an intrusion detection system is
    the assessment capability associated with the perimeter intrusion alarm
    system. Alternative assessment capabilities such as video assessment,
    hardened observation posts, and armored response vehicles are discussed
    in Regulatory Guide 5.61, "Intent and Scope of the Physical Protection
    Upgrade Rule Requirements for Fixed Sites," in the discussion of
    paragraph 73.46(h)(6). System design considerations for video
    assessment systems are discussed in Section 6.3 of the IDSH.
    The following discussion describes the operations, limitations,
    and environmental considerations of six basic types of commercially
    available perimeter alarm systems: microwave, E-field, ferrous metal
    detector, pressure-sensitive, infrared, and vibration- or stress-fence
    protection systems.
1. Microwave Perimeter Alarm System
    Each link of a microwave perimeter alarm system is composed of a
    transmitter, receiver, power supply, signal processing unit, signal
    transmission system, and annunciator. The microwave transmitter produces
    a beam-like pattern of microwave energy directed to the receiver, which
    senses the microwave beam. A partial or total interruption of the beam
    will cause an alarm. The microwave beam can be modulated to reduce
    interference from spurious sources of radiofrequency energy, to increase
    sensitivity, and to decrease the vulnerability to defeat from "capture"
    of the receiver by a false microwave source.
    Successive microwave links can be overlapped to form a protective
    perimeter around a facility. Since the transmitter/receiver link is a
    line-of-sight system, hills or other obstructions will interrupt the
    beam, and ditches or valleys may provide crawl space for an intruder.
    Moreover, objects such as tumbleweed, paper, and bushes moving in the
    path of the beam can cause nuisance alarms. Since the beam is wider
    than other systems, care must be taken to ensure that authorized
    activities do not create nuisance alarms. Systems using the Doppler
    shift for motion detection are especially sensitive to the motion of
    trees and grass and to falling rain and snow.
    The maximum and minimum separation of the transmitter and receiver
    is usually specified by the manufacturer. Typically, a microwave
    perimeter alarm system will operate effectively in the range between 70
    and 150 meters.
2. E-Field Perimeter Alarm System
    An E-field perimeter alarm system consists basically of a field
    generator that excites a field wire, one or more sensing wires, and a
    sensing filter; an amplifier; and a discriminatory and annunciator unit.
    The field wire transmits essentially an omnidirectional E-field to
    ground. A large body approaching the system changes the pattern of the
    E-field. When sensing wires are placed at different locations within
    the transmitted E-field pattern, they pick up any changes occurring in
    that pattern. If the changes are within the frequency bandpass of human
    movement, an alarm signal is generated. The field wire and one or more
    parallel sensing wires can be either connected to a chain link fence or
    mounted as an above-ground, freestanding system of an isolation zone.
    The E-field system can offer about 300 meters of perimeter
    protection per segment, but shorter lengths of 100 meters are
    recommended in order to have effective alarm assessment and response
    capabilities. The system can be mounted on metal, plastic, or wooden
    posts using specially designed electrical isolators that allow for small
    movements of the posts without disturbing the field and sensing wires.
    Both the field and sensing wires need to be under a high degree of
    spring tension to produce high-frequency vibrations when they are struck
    by small foreign objects or blown by the wind, both of which are out of
    the passband of the receiving circuitry. In addition, in order to keep
    the sensitivity of the system from varying, the E-field detector needs
    to be well grounded.
    The E-field detector is not a line-of-sight system and therefore
    can be installed on uneven terrain and in an irregular line. The
    surrounding terrain should be kept clear of shrubs, tree limbs, and
    undergrowth since they act as moving ground objects. The basic system
    is a two-wire system with the sensing wire located between 200 and 450
    millimeters above the ground and the field wire located approximately 1
    meter above and parallel to the sensing wire. The width of the
    detection zone is variable and depends to a large degree on the size of
    the target. Generally, it is approximately 0.6 meter wide on either
    side of the field wire. To prevent an intruder from jumping over the
    top of the E-field detector, a second sensing wire can be installed
    approximately 1 meter above the field wire. When installed on a chain
    link fence, standoffs approximately 0.5 meter long are used for mounting
    the wires. The E-field generated in this configuration does not
    penetrate the fence but parallels it.
3. Ferrous Metal Detector Perimeter Alarm System
    A ferrous metal detector system consists of buried electrical
    cables, amplifiers, inhibitors, power supply, signal processing unit,
    signal transmission lines, and annunciator. The system is passive and is
    susceptible to changes in the earth's ambient magnetic field. Such
    changes are caused either by electromagnetic disturbances such as
    lightning or by ferrous metal being carried over the buried cables. The
    change in the local ambient magnetic field induces a current in the
    buried cable which is filtered and sensed by the electronics. If the
    change exceeds a predetermined threshold, an alarm is generated. To
    reduce nuisance alarms from external electromagnetic sources (e.g.,
    electrical power transmission lines), the electrical cable is laid in
    loops that are transposed at regular intervals. Also, an inhibitor loop
    can be used to reduce nuisance alarms from electromagnetic interference.
    The inhibitor, which operates on the same principle as the sensor cable
    loops and is buried near the sensor cable, senses strong temporary
    electromagnetic interferences (e.g., lightning) and disables the alarm
    system for approximately one second, thus reducing nuisance alarms.
    The ferrous metal detector system is not a line-of-sight system
    and therefore can be installed on uneven ground in an irregular line.
    The sensor subloops formed by the cables must be fairly regular,
    however. Since the system will detect only ferrous metal, animals,
    birds, or flying leaves will not initiate alarms. However,
    electromagnetic interferences can cause nuisance alarms or disable the
    alarm system when the interference is severe.
    Each sensing cable (and amplifier) can monitor a security segment
    up to 500 meters in length. Increasing the length of the security
    segment beyond 500 meters usually results in a high nuisance alarm rate.
    Multiple cables and amplifiers can be used to extend the monitoring
    length.
4. Pressure/Strain-Sensitive Perimeter Alarm System
    Buried pressure/strain transducers detect small variations in the
    mechanical stress exerted on the surrounding soil by the presence of an
    individual passing above the sensor. The signals produced by the
    transducers are amplified and compared with a preestablished threshold.
    If the signal exceeds the threshold, an alarm occurs. The transducer
    may be a set of piezoelectric crystals, a fluid-filled flexible tube, a
    specially fabricated stress/strain electrical cable, or an insulated
    wire in a metallic tube.
    Like the ferrous metal detector system, the pressure-sensitive
    system does not require line-of-sight installation and can be sited on
    uneven terrain. However, soil condition and composition have a
    significant effect on sensor sensitivity. Installation in rocky soil may
    result in damage to the pressure transducers either during installation
    or as a result of soil settlement after installation. Wind-generated
    movement in trees and poles can create nuisance alarms. High winds can
    produce pressure waves on the ground surface which, if sensed by the
    transducer, could necessitate operation at reduced sensitivity in order
    to avoid nuisance alarms. Features to compensate for wind-generated
    noise can be designed into the equipment but in turn may cause a
    decrease in system sensitivity. Pressure systems will lose sensitivity
    when the buried sensors are covered by snow, by snow with a frozen crust
    that will support the weight of a man, or by frozen ground. Other
    natural phenomena such as hail and rain can cause nuisance alarms.
    The sensitive area consists of a narrow corridor, usually about 1
    meter in width. A greater degree of security can be achieved by
    employing two such corridors to prevent an intruder from jumping over
    the buried transducers. A typical length monitored by a transducer
    (i.e., set of piezoelectric crystals, a liquid-filled tube, or an
    electrical cable) is about 100 meters.
5. Infrared Perimeter Alarm System
    Like the microwave system, each link of an infrared system is
    composed of a transmitter, receiver, power supply, signal processor,
    signal lines, and alarm annunciator. The transmitter directs a narrow
    infrared beam to a receiver. If the infrared beam between the
    transmitter and receiver is interrupted, an alarm signal is generated.
    As with the microwave system, the infrared system is a line-of-sight
    system. In addition, the infrared beam is usually modulated. Since the
    infrared beam does not diverge significantly as does the microwave beam,
    multiple infrared beams between transmitter and receiver can be used to
    define a "wall." If this "wall" is then penetrated by an individual, an
    alarm will result.
    Fog both attenuates and disperses the infrared beam and can cause
    nuisance alarms. However, the system can be designed to operate
    properly with severe atmospheric attenuation. Dust on the faceplates
    will also attenuate the infrared beam as will an accumulation of
    condensation, frost, or ice on the faceplates.
    Such condensation, frost, or ice, however, may be eliminated
    through the use of heated faceplates. Sunshine on the receiver may
    cause an alarm signal. Misalignment of transmitter and receiver caused
    by frost heaves may also cause an alarm signal. Like the microwave
    system, vegetation such as bushes, trees, or grass and accumulated snow
    will interfere with the infrared beam, and ditches, gullies, or hills
    will allow areas where the passage of an intruder may go undetected.
    The typical distance between transmitter and receiver is about 100
    meters; some systems are capable of monitoring a distance up to 300
    meters under ideal conditions.
6. Vibration- or Strain-Detector Perimeter Alarm System
    A variety of devices that detect strain or vibration are available
    for use as fence protection systems. Although the devices vary greatly
    in design, each basically detects strain or vibration of the fence such
    as that produced by an intruder climbing or cutting the fence. In the
    simplest devices, the vibration or strain makes or breaks electrical
    continuity and thereby generates an alarm. Vibration- or
    strain-detection devices for fence protection generally are susceptible
    to nuisance alarms caused by wind vibrating the fence or by hail stones
    or large pieces of trash blowing against the fence. The frequency of
    nuisance alarms due to the wind can be reduced by rigidly mounting the
    fence and thereby lessening the propensity of the fence to vibrate in
    the wind. This situation is especially common with post-mounted
    switch-contact-type alarm systems. The use of electronic signal
    processing equipment in conjunction with signal-generating strain
    transducers can effectively reduce nuisance alarm rates without
    sacrificing sensitivity to climbing or cutting the fence. However, most
    fence alarm systems can be easily bypassed by a variety of methods.
    Depending on the variety of sensor, each sensor can monitor a
    length of fence ranging from about 1 meter to several hundred meters.
C. REGULATORY POSITION
1. Minimum Qualification for Perimeter Intrusion Alarm Systems
    a. General
    (1) Electrical. All components--sensors, electronic
    processing equipment, power supplies, alarm monitors--should be capable
    of meeting the typical design requirements for fire safety of nationally
    recognized testing laboratories such as Underwriters Laboratory (UL) or
    Factory Mutual (FM). The system should contain provisions for automatic
    switchover to emergency battery and generator or emergency battery power
    without causing an intrusion system alarm in the event primary power is
    interrupted. Emergency power should be capable of sustaining operation
    for a minimum of 24 hours without replacing or recharging batteries or
    refueling generators. If sufficient battery or fuel capacity is not
    attainable for 24-hour operation as stated above, additional batteries
    or fuel should be stored on site expressly for augmenting the emergency
    power supply. If emergency power is furnished by battery, all batteries
    (including stored batteries) should be maintained at full charge by
    automatic battery-charging circuitry. Batteries should be checked in
    accordance with IEEE Standard 450-1975 as endorsed by Regulatory Guide
    1.129, "Maintenance Testing and Replacement of Large Lead Storage
    Batteries for Nuclear Power Plants," and IEEE Standard 308-1974 as
    endorsed by Regulatory Guide 1.32, "Criteria for Safety-Related Electric
    Power Systems for Nuclear Power Plants."
    (2) Tamper Indication. All enclosures for equipment
    should be equipped with tamper switches or triggering mechanisms
    compatible with the alarm systems. The electronics should be designed
    so that tamper-indicating devices remain in operation even though the
    system itself may be placed in the access mode.(1)----------
    (1) Access mode means the condition that maintains security over
    the signal lines between the detector and annunciator and over the
    tamper switch in the detector but allows access into the protected area
    without generating an alarm.
    ----------
    All controls that affect the sensitivity of the alarm
    system should be located within a tamper-resistant enclosure. All signal
    lines connecting alarm relays with alarm monitors should be supervised;
    if the processing electronics is separated from the sensor elements and
    not located within the detection area of the sensor elements, the signal
    lines linking the sensors to the processing electronics should also be
    supervised.(2) All key locks or key-operated switches used to protect
    equipment and controls should have UL-listed locking cylinders (see
    Regulatory Guide 5.12, "General Use of Locks in the Protection and
    Control of Facilities and Special Nuclear Materials").
    (3) Environment. Perimeter intrusion alarm systems should
    be capable of operating throughout the climatic extreme of the environs
    in which they are used; as a minimum, the outdoor systems should be
    capable of effective operation between -35degreesC and +50degreesC.
    Components that necessarily must be located out of doors should be
    protected from moisture damage by such methods as hermetic sealing,
    potting in an epoxy compound, conformal coating, or watertight
    enclosures.
    (4) Alarm Conditions. Perimeter intrusion alarm systems,
    whether using single or complementary sensors, should generate an alarm
    or indication under any of the following conditions:
    (a) Detection of stimulus or a condition for which
    the system was designed to react,
    (b) Indication of a switchover to the emergency or
    secondary source(s) of power and also upon loss of emergency power,
    (c) Indication of tampering (e.g., opening,
    shorting, or grounding of the sensor circuitry) which renders the device
    incapable of normal operation,
    (d) Indication of tampering by activation of a
    tamper switch or other triggering mechanism,
    (e) Failure of any component(s) to the extent that
    the device is rendered incapable of normal operation. Self-checking
    circuitry is normally used for detecting components that have failed in
    a device.
    Under normal environmental conditions, including
    seasonal extremes, the total perimeter alarm system should not average
    more than one false alarm per week per segment and should not average
    more than one nuisance alarm per week per segment while maintaining
    proper detection sensitivity. Where the segment can be fully observed
    at all times, either visually or by closed circuit television, the false
    alarm rate and nuisance alarm rate may be increased to one alarm per day
    per segment. False alarms are defined as those alarms that have been
    generated without any apparent cause. Nuisance alarms are alarms
    generated by an identified input to a sensor or monitoring device that
    does not represent a safeguards threat. Proper detection probability is
    defined as the ability to detect an intruder with at least 90%
    probability for each segment of the isolation zone under the conditions
    stated in the Performance Criteria of each type of alarm system.
    ----------
    (2) Signal line supervision is discussed in NUREG-0320, "Interior
    Intrusion Alarm Systems," issued in February 1978.
    ----------
    An automatic and distinctly recognizable indication
    should be generated by the alarm monitor upon switchover to emergency
    power. Loss or reduction of power (either primary or emergency) to the
    degree that the system is no longer operating properly should also be
    indicated in the central alarm station.
    Placement of any portion of a perimeter intrusion
    alarm system into the access mode should be indicated automatically and
    distinctly by the alarm monitor. Moreover, the segment(s) of the system
    placed in the access mode should be indicated clearly.
    (5) Installation. It is recommended that perimeter
    intrusion alarm systems be located inside the perimeter physical barrier
    at a distance that prohibits use of the barrier to illicitly traverse
    the alarm zone. If, however, installation is outside the perimeter
    barrier, a second barrier or a fence (e.g., a cattle or snow fence)
    should be erected so that the alarm system is located between the
    barriers. The second barrier or fence will serve to reduce the
    incidence of nuisance alarms from animals and passersby. The separation
    between the second barrier and the perimeter barrier should be
    sufficient to preclude bridging of the perimeter alarm system; in all
    cases, it should not be less than 6 meters. Fence protection systems
    should be located on an inner fence.
    Where possible, the perimeter should be segmented so
    that an individual standing at one end of a segment will have a clear
    view of the entire segment. In no case should any segment exceed 200
    meters in length. Each segment should independently and uniquely
    indicate intrusion and should be capable of placement into the access
    mode independently of the other segments.
    b. Microwave Perimeter Alarm System
    (1) Performance Criteria. A microwave perimeter alarm
    system should be capable of detecting an intruder weighing a minimum of
    35 kilograms passing between the transmitter and receiver at a rate
    between 0.15 and 5 meters per second, whether walking, running, jumping,
    crawling, or rolling. The beam should be modulated, and the receiver
    should be frequency selective to decrease susceptibility to receiver
    "capture." Generally, because of susceptibility to motion beyond the
    area to be protected, monostatic Doppler microwave systems should not be
    used as perimeter intrusion alarms.
    (2) Installation Criteria. The transmitters and receivers
    should be installed on even terrain clear of trees, tall grass, and
    bushes. Each unit should be mounted rigidly at a distance of about 1
    meter above the ground. Because of variances in the antenna pattern of
    different microwave systems, this height may have to be varied slightly
    in order to obtain proper ground coverage. The distance between a
    transmitter and its receiver should be in accordance with the
    manufacturer's specifications and site-specific requirements. Neither
    the transmitter nor the receiver should be mounted on a fence. To
    prevent passage under the microwave beam in the shadow of an
    obstruction, hills should be leveled, ditches filled, and obstructions
    removed so that the area between transmitter and receiver is clear of
    obstructions and free of rises or depressions of a height or depth
    greater than 15 cm. The clear area should be sufficiently wide to
    preclude generation of alarms by objects moving near the microwave link
    (e.g., personnel walking or vehicular traffic). Approximate dimensions
    of the microwave pattern should be provided by the manufacturer.
    If the microwave link is installed inside and roughly
    parallel to a perimeter fence or wall, the transmitter and receiver
    should be positioned so as to prevent someone from avoiding detection by
    jumping over the microwave beam into the protected area from atop the
    fence or wall. Typically, a chain link security fence with an overall
    height of 2.4 meters will necessitate a minimum of 2 meters between the
    fence and the center of the microwave beam.
    Successive microwave links and corners should overlap
    at least 3 meters to eliminate the dead spot (areas where movement is
    not detected) below and immediately in front of transmitters and
    receivers. The overlap of successive links should be arranged so that
    receiver units are within the area protected by the microwave beam.
    c. E-Field Perimeter Alarm System
    (1) Performance Criteria. An E-field perimeter alarm
    system should be able to detect an individual weighing a minimum of 35
    kilograms at least 0.5 meter from the sensing wire whether crawling and
    rolling under the lower sensing wire, stepping and jumping between the
    field and sensing wires, or jumping over the top sensing wire of the
    system. The field and sensing wires should be supervised to prevent the
    undetected cutting or bypassing of the system through electronic or
    clandestine means. The system design should employ techniques to
    minimize alarms caused by high winds, thunderstorm-related electrical
    phenomena, and small animals.
    (2) Installation Criteria. The E-field sensor should
    consist of a minimum of one field wire and two sensing wires. One
    sensing wire should be located no more than 0.45 meter above ground
    level with the second located approximately 2.6 meters above ground
    level. The field wire should be located between the sensing wires
    approximately 1 meter above ground level. The surrounding terrain
    within 3 meters of E-field wires should be free of all shrubs, trees,
    and undergrowth. The control unit should be well grounded using a
    1-meter or longer grounding rod or equivalent electrical ground. When
    mounted to a chain link fence, the fence should also be well grounded
    approximately every 23 meters using a 1-meter or longer grounding rod or
    equivalent electrical ground.
    d. Ferrous Metal Detector Perimeter Alarm System
    (1) Performance Criteria. A ferrous metal detector
    perimeter alarm system should be able to detect a 400-pole-centimeter
    (CGS units) magnet moving at a rate of 0.15 meter per second within a
    radius of 0.3 meter of a sensor cable. The detection system should be
    equipped with inhibitor coils to minimize nuisance alarms due to
    electromagnetic interference. No more than six sensing loops per
    inhibitor coil should be used in order to prevent simultaneous
    desensitizing of the entire system.
    (2) Installation Criteria. To determine if the ferrous
    metal detection system will operate in the proposed environment, a
    preengineering site survey should be made using an electromagnetic
    detection survey meter. This survey meter can be furnished by the
    manufacturer. If the electromagnetic disturbances are within the limits
    prescribed by the manufacturer, this type of system can be used
    effectively. Special looping configurations can be made in areas of
    high electromagnetic interference to reduce the incidence of nuisance
    alarms.
    The sensing loops of electrical cable should be buried
    in the ground according to the manufacturer's stated depth. Multiple
    units (cable and amplifier) should be used to protect a perimeter. All
    associated buried circuitry should be buried within the protected zone
    and packaged in hermetically sealed containers. The cable should be
    laid in accordance with the manufacturer's recommended geometrical
    configurations to reduce nuisance alarms from external sources. When
    cable is being installed in rocky soil, care should be taken to remove
    sharp rocks during backfilling over the cable.
    Inhibitors should be buried in the ground at least 6
    meters from the cable inside the protected perimeter.
    Continuous electromagnetic interference obstructs the
    detection of an intruder carrying metal over the buried cable by keeping
    the inhibitor activated, thereby preventing the alarm unit from
    responding to a change in flux caused by the intruder. The device
    should therefore be used only where the environment is relatively free
    of severe man-made electromagnetic interference (e.g., overhead power
    cables, pole-mounted transformers, generators). The cable should never
    be installed close to overhead power transmission lines. Moreover, the
    cable should be placed at least 3 meters from parallel-running metal
    fences and at least 20 meters from public roads to minimize nuisance
    alarms.
    e. Pressure-Sensitive Perimeter Alarm System
    (1) Performance Criteria. A pressure-sensitive perimeter
    alarm system should be capable of detecting an individual weighing more
    than 35 kilograms crossing the sensitive area of the system at a minimum
    speed of 0.15 meter per second, whether walking, crawling, or rolling.
    The system design should employ techniques (e.g., electronic signal
    processing) to eliminate nuisance alarms from wind and other adverse
    environmental phenomena.
    (2) Installation Criteria. The sensors should be
    installed at the depth below the ground surface stated by the
    manufacturer. To obtain a high probability of detection, the sensors
    should be in two separate parallel lines at a distance of 1.5 to 2
    meters apart. The sensors and electronic circuitry buried in the ground
    should be of a durable, moistureproof, rodent-resistant material. When
    a pressure-sensitive perimeter alarm system is being installed in rocky
    soil, all rocks should be removed during backfilling to prevent damage
    to sensors. If the frost line exceeds 10 cm, a buried
    pressure-sensitive system should not be used unless the soil is
    specifically prepared to eliminate freezing above the sensor.
    f. Infrared Perimeter Alarm Systems
    (1) Performance Criteria. An infrared perimeter alarm
    system should be a multibeam modulated type consisting of a minimum of
    three transmitters and three receivers per unit. An infrared perimeter
    alarm system should be capable of detecting an individual weighing a
    minimum of 35 kilograms passing between the transmitters and receivers
    at a rate between 0.15 and 5 meters per second, whether walking,
    running, jumping, crawling, or rolling. Furthermore, the systems should
    be able to operate as above with a factor of 20 (13db) insertion loss
    due to atmospheric attenuation (e.g., fog) at maximum range (100
    meters).
    (2) Installation Criteria. An infrared perimeter alarm
    system should be installed so that, at any point, the lowest beam is no
    higher than 21 cm above grade and the highest beam at least 2.6 meters
    above ground. Sufficient overlap of beams should exist such that an
    individual could not intrude between the beams and remain undetected.
    The ground areas between the infrared beam posts should be prepared to
    prevent tunneling under the lower beam within at least 15 cm of the
    surface. This may be accomplished by using concrete, asphalt, or a
    similar material in a path at least 1 meter wide and 15 cm deep or
    alternatively 15 cm wide and 1 meter deep between the posts.
    The transmitters and receivers should be mounted
    rigidly (e.g., installed on a rigid post or concrete pad) to prevent
    nuisance alarms from vibrations. Each transmitter and receiver post
    should be provided with a pressure-sensitive cap to detect attempts at
    scaling of or vaulting over the infrared beam post. The maximum
    distance between transmitter and receiver should be selected to permit
    proper operation during conditions of severe atmospheric attenuation
    that are typical for the site, generally a maximum of 100 meters.
    It is recommended that the infrared perimeter alarm
    system be installed inside the physical perimeter barrier with the
    transmitter and receiver units positioned a minimum of 3 meters from the
    barrier. Installation of the infrared alarm system inside and directly
    adjacent to the perimeter barrier should be avoided since the barrier
    may provide a solid base from which an intruder can jump over the beams
    into the protected area.
    g. Vibration or Strain Detection
    This vibration- or strain-detection system should be used
    only as a secondary or backup perimeter alarm system except when one of
    the other five types of perimeter alarm systems will not work (e.g.,
    because of the environment) and after the NRC's approval has been
    received. If there is a need to use this system, the following criteria
    should apply:
    (1) Performance Criteria. Vibration- or strain-detection
    systems used for fence protection should detect an intruder weighing
    more than 35 kilograms attempting to climb the fence. The system should
    also detect any attempt to cut the fence or lift the fence more than 15
    cm above grade. The system should not generate alarms due to wind
    vibration of the fence from a wind force of up to 48 kilometers/hour.
    (2) Installation Criteria. The vibration or strain
    sensors should be attached firmly to the fence (post or fabric, as
    appropriate) so that the vibration/stress caused by an intruder
    climbing, cutting, or lifting the fence will generate an alarm.
2. Testing of Perimeter Intrusion Alarm Systems
    All tests and test results should be documented. The documented
    test results will establish the performance history of each perimeter
    alarm system and each segment of the isolation zone. The test results
    should be available for inspection and analysis.
    a. Operability Testing
    Perimeter intrusion alarm systems should be tested on all
    segments of the isolation zone at least once each 7 days. Testing may be
    conducted during routine patrols by the members of the licensee security
    force. The testing should be conducted by crossing the segment of the
    isolation zone where the alarm system is located or by climbing the
    fence to which the system is attached to provide the required alarm
    stimulus. Where appropriate, a specific test procedure should be
    followed. Prior to making the test, the individual making the test
    should notify the central alarm station that a test is about to be
    conducted. The area under test should be maintained under visual
    observation by a member of the security organization.
    All segments of the isolation zone should be tested in a
    different, preferably random, order every 7 days and the testing should
    be conducted throughout the week, not all tests on 1 day. The
    operability testing should result in 100% detections on all segments
    each 7 days. If the perimeter alarm system fails to detect an intrusion
    on one or more segments, corrective actions should be taken and
    documented. See the operability testing section of Appendix A to this
    guide for a sample method for determining the testing order for the
    segments and a suggested method for determining if the detection rate of
    the perimeter alarm system has decreased to below 90%. Other testing
    methods may be used if the methods are fully documented and approved by
    the NRC.
    b. Performance Testing
    At least quarterly, i.e., once each 93 calendar days, after
    each inoperative state, and after any repairs, the perimeter intrusion
    alarm system should be tested against its manufacturer's design
    specifications and for proper detection probability. An inoperative
    state for an alarm system or component exists when (1) the power is
    disconnected to perform maintenance or for any other reason, (2) both
    primary and backup power sources fail to provide power, and (3) when
    power is applied and one or more components fail to perform their
    intended function. Placing a properly operating alarm system in the
    access mode would not constitute an inoperative state unless
    accompanying or followed by any of the above three conditions.
    (1) Specification Testing. The test procedure recommended
    by the manufacturer should be followed. While the test is being
    conducted, the area under test should be maintained under visual
    observation by a member of the security organization. For all perimeter
    systems, tests should be conducted to verify that no obvious dead spots
    exist in the segment of protection. As a minimum, the tests should
    include line supervision and tamper proofing when testing in both the
    access and secure modes. If the perimeter alarm system does not meet
    the manufacturer's specifications, corrective actions should be taken
    and documented.
    (2) Detection Probability Testing. Proper detection
    probability is defined as the ability to detect an intruder with at
    least 90% probability in each segment of the isolation zone, with 95%
    confidence, under the conditions stated in the Performance Criteria of
    each type of alarm system. While the detection probability testing is
    being conducted, the area under test should be maintained under visual
    observation by a member of the security organization. One sample
    testing method for demonstrating compliance with detection probability
    and confidence levels is given in the detection probability testing
    section of Appendix A to this guide. Other testing methods may be used
    if the methods are fully documented and approved by the NRC.
D. IMPLEMENTATION
    The purpose of this section is to provide information to
    applicants and licensees regarding the NRC staff's plans for using this
    regulatory guide.
    Except in those cases in which the applicant or licensee proposes
    an acceptable alternative method, the staff will use the methods
    described herein in evaluating an applicant's or licensee's capability
    for and performance in complying with specified portions of the
    Commission's regulations after April 1, 1980.
    If an applicant or licensee wishes to use the method described in
    this regulatory guide on or before April 1, 1980, the pertinent portions
    of the application or the licensee's performance will be evaluated on
    the basis of this guide.
    VALUE/IMPACT STATEMENT
    A separate value/impact analysis has not been prepared for the
    proposed revision to this regulatory guide. The changes were made to
    make the guide consistent with the upgraded physical protection
    amendments to the regulations published in final form in the Federal
    Register of November 28, 1979 (44 FR 68184). A value/impact analysis
    prepared for the proposed amendments was made available in the
    Commission's Public Document Room at the time the proposed amendments
    were published. This analysis is appropriate for the final amendments
    as well as for the regulatory guide revisions appropriate to those
    amendments.
    APPENDIX A(*)EXAMPLES OF TESTING METHODS FOR PERIMETER INTRUSION ALARM SYSTEMS
    BACKGROUND
    The purpose of this appendix is to provide an example of a testing
    method to determine detection capability of perimeter intrusion alarm
    systems. This example should not be interpreted as a regulatory
    requirement. Other testing methods for determining compliance with
    detection probability and confidence levels may be used if fully
    documented and approved by the NRC. The purpose of testing a perimeter
    intrusion alarm system is to ensure that the installed system is
    operating according to the three testing criteria stated below.
1. Operability Testing - Paragraph C.2.a of this guide states:
    "Perimeter intrusion alarm systems should be tested on all
    segments of the isolation zone at least once each 7 days.... The
    operability testing should result in 100% detections on all
    segments each 7 days."
2. Specification Testing - Paragraph C.2.b of this guide states: "At
    least quarterly,...the perimeter intrusion alarm system should be
    tested against its manufacturer's design specifications..."
3. Detection Probability Testing - Paragraph C.2.b(2) states: "Proper
    detection probability is defined as the ability to detect an
    intruder with at least 90% probability in each segment of the
    isolation zone, with 95% confidence..."
    DEFINITIONS
    In order to ensure uniform testing, the following terms are
    defined:
1. Zone (Isolation Zone) - The entire perimeter adjacent to the
    protected area.
2. Segment - A portion of the isolation zone that is independently
    alarmed and monitored.
3. Running - Entering and leaving the zone of detection at an
    approximately velocity of 5 meters per second.
4. Walking - Entering and leaving the zone of detection with a normal
    stride.
5. Crawling - Entering and leaving the zone of detection by lying
    prone to the ground, perpendicular to the zone of detection, with
    a low profile at an approximate velocity of 0.15 meter per second.
6. Jumping - Leaping from a height above the zone of detection to a
    point at ground level across the zone of detection, e.g., standing
    on the fence and attempting to leap across the zone of detection.
7. Rolling - Entering and leaving the zone of detection prone to the
    ground with a low profile, parallel to the zone of detection, and
    rolling slowly at an approximate velocity of 0.15 meter per
    second.
    ----------
    (*) Although this appendix is a substantive addition to Revision
    2, no lines are added in the margin.
    ----------
    TESTING
    Operability Testing
    Operability testing is a check to ensure that the alarm system is
    operating and that the detection sensitivity of the alarm system has not
    decreased from the 90% detection rate. The perimeter alarm systems
    should be tested on each segment of the isolation zone at least once
    during a 7-day period. For example, the guard may violate the detection
    field by walking through the sensitive zone. The ordering of the tests
    on the segments should be in a different, preferably random, order each
    week, and the testing should be conducted throughout the week. For an
    example of randomizing the segments, assume that there are 10 segments
    and 21 shifts per week (3 shifts per day and 7 days per week). Select
    at random (using a random number table or a random number generator) 10
    of the shifts out of the 21 possible shifts, retaining the order in
    which the shifts were drawn. Then pair these 10 shifts with the
    segments 1 through 10. In this example, let the 10 shifts selected be
    6, 14, 9, 6, 20, 16, 19, 18, 10, 7.
    (Due to database constraints, Tables 1-7 are not included. Please
    contact LIS to obtain a copy.) The segment to be tested on each day of the week and the specific
    shift (1, 2, or 3) can be seen more clearly by reorganizing this
    information (see Table 2).
    The testing could be conducted such that no shift tests more than
    one segment if the number of segments is less than the number of shifts.
    There are many other possible methods for ordering the segments,
    depending on the number of segments and the number of shifts. For
    example, if there are more segments than shifts, the ordering method
    could require that each shift test at least one segment.
    The test results should be documented on a success/failure basis.
    If the test on a segment results in a failure, corrective actions should
    be taken and documented. For example, if the test of a segment results
    in no alarm, the alarm system should be checked for an obvious problem
    such as an incorrect setting and should be retested four more times
    during the same shift if possible. If all four of these tests result in
    alarms, the alarm system on the segment should be tested five more times
    on the next day. If all these five tests result in alarms, the weekly
    testing schedule for this segment can be resumed since the 90% detection
    rate can be confirmed. If any failures occurred during the nine
    additional tests, the alarm system for the segment will need to be
    thoroughly checked, repaired, and retested according to the detection
    probability testing method to demonstrate that the alarm system for the
    segment is now detecting intrusions with at least a 90% detection rate,
    with 95% confidence. A table similar to Table 3 (see page 5.44-11) may
    be used for recording the test results.
    Specification Testing
    The licensee should conduct a manufacturer's design specification
    test of the system under test before the detection probability tests
    have been conducted on all segments and the results documented. The
    licensee should follow the test procedures recommended by the
    manufacturer of that system. If the system does not meet the
    manufacturer's specifications, the recommended actions include retesting
    and calling the manufacturer's representative for repairs or upgrading
    of the system.
    Detection Probability Testing
    The following is one example of a method for detection probability
    testing:
1. Determine the most vulnerable area of each segment, and determine
    the method of approach most likely to penetrate that segment,
    i.e., walking, running, jumping, crawling, rolling, or climbing.
    This determination will, in most cases, be terrain dependent.
2. Test all segments using all the applicable penetration approaches
    at the most vulnerable area 30 times initially, after installing a
    new system, after repairing or upgrading the system, or after the
    system failed to meet the minimum number of the successful
    detection criterion given below. All 30 tests must have resulted
    in successful detections of the intrusion in order to have at
    least a 90% probability of detection, with 95% confidence.
    If the minimum number of successful detections is not achieved,
    the system should be checked. If no problems with the system are
    discovered, 10 more tests should be made and if the minimum number
    of successful detections is achieved for the new number of tests
    (given in Table 4), in this case 39 out of 40, the testing can be
    ended for this segment for this quarter. If no problems with the
    system can be discovered and the minimum number of successful
    detections is not achieved after one more test of 10 intrusions,
    the system would need to be upgraded to increase the detection
    probability to the required level. If problems with the systems
    are discovered, the system should be repaired and 30 new tests
    performed. If there are 30 successful detections, testing can be
    ended.
    For the subsequent tests at 90-day intervals, each segment should
    be tested 10 times. Each segment should show at least 9
    successful detections out of 10 approaches and the cumulative
    results (combining the present results with the results from
    previous quarters) should have at least the minimum number of
    successful detections given in Table 4.
3. Attempt all applicable penetration approaches for a
    man-on-the-ground target. The penetration approach most likely
    not to be detected should be attempted more frequently if an equal
    number of tests per approach is not possible. For example, if the
    applicable penetration approaches for a given segment in the
    system are running, walking, and crawling, the 10 quarterly tests
    would be divided among the 3 approaches. If crawling has the
    worst detection record, running would be attempted three times,
    walking three times, and crawling four times.
4. Randomize the order in which the segments are tested.
    Randomization is a means of ensuring that environmental effects
    and other unknown factors that may affect the test results
    (detection or nondetection) do not always favor or handicap the
    same segment or method of approach. For example, if Segment 1 is
    always tested in the morning and Segment 2 is always tested in the
    afternoon and if the derection equipment is slightly more
    sensitive to intrusions in the morning, the conclusion might be
    drawn, based on the test results, that Segment 2 is less protected
    than Segment 1. However, the difference noted between the two
    segments might be due only to the morning vs. afternoon
    difference. Similarly, by randomizing the methods of approach, no
    approach will be continually favored if the time sequence
    (ordering) affects the test results. Randomization is protection
    against disturbances that may or may not occur and that may or may
    not be serious if they do occur. Randomization can be
    accomplished by using a random numbers table to assign the order
    in which the segments will be tested.
5. Maintain records of the results of all tests performed. Included
    in these records should be the segment number, date, time, and
    relevant environmental conditions when tests were performed.
    Table 5 (see page 5.44-13) provides a suggested format for
    recording the test results. The test results in the "Overall"
    (totals) row in the columns headed (b), (c), (b'), and (c') are
    the important summary values. For the initial testing or when
    retesting the perimeter alarm system after it has failed to meet
    the minimum number of successful detections given in Table 4, the
    (b) and (c) values should be 30 and 30, or 39 and 40, or 48 and
    50. For the subsequent quarterly testing, (b) must be 9 or 10 and
    (c) is 10 and (b') must be at least the number under "Minimum No.
    of Successful Detections" for the (c') value ("Total No. of
    Tests") in Table 4.
    Detection Probability Statements
    One method for assessing the probability of detection of the
    entire detection system is to use the "chain model," i.e., the weakest
    "link" in the system determines the probability of detection for the
    system. In this case, the approach to a particular segment that has the
    lowest probability of detection would equal the probability of detection
    for the system. This is a "worst case" approach; however, it is the
    vulnerable areas of the system that need to be discovered and
    eliminated.
    One of the problems in testing intrusion-detection systems is the
    need for a large number of tests to be performed on each segment to
    estimate well the probability of detection in each segment. One example
    of a method to be used to avoid performing a large number of tests on
    each segment each quarter is to use an empirical Bayesian approach to
    estimate the probability of detection. The empirical Bayesian method(1)
    combines the present quarter's data with those of previous quarters.
    Using the empirical Bayesian method, the performance criterion can be
    tested without a large number of tests being performed each quarter.
    For the total number of tests less than 100 on each segment, the
    performance criteria are relaxed to be "at least 88% probability of
    detection in a segment with 95% confidence." When the number of tests is
    100 or more, the performance criterion of "at least 90% probability of
    detection in a segment with 95% confidence" is used.
    Table 6 gives the probability statements for the number of tests
    between 30 and 120 with a given minimum number of successful detections.
    For example, one is 95% sure that the probability of detection is
    at least 89.8% for the test results of 95 successful detections out of
    100 tests, i.e., the lower 95% confidence limit for the probability of
    detection is 89.8%.
    Appendix B to this guide gives the details for deriving these
    statements. Table 1 in Appendix B gives the probability statements
    associated with all the numbers of successful detections out of the
    total number of tests performed that result in at least a 90%
    probability of detection with a 95% confidence level. The total number
    of tests covered in this table range from 30 to 120 in increments of 10
    tests.
    Using Table 1 in Appendix B, stronger statements can be made about
    the probability of detection for the number of successful detections
    greater than the minimum number. For example, if there were 98
    detections out of 100 tests, one should state: "The probability of
    detection is at least 93.8% with 95% confidence."
    ----------
    (1) For a discussion of Bayesian methods, see H. F. Martz, Jr.,
    and R. A. Waller, "The Basics of Bayesian Reliability Estimation from
    Attribute Test Data," Los Alamos Scientific Laboratory Report LA-6126,
    February 1976.
    ----------
    In addition to the overall lower confidence limit on the
    probability of detection for a segment considered previously, a point
    estimate can be computed for the probabilities of detection for each
    method of approach for each segment, as well as a point estimate for the
    overall probability of detection for each segment. The point estimate
    of a probability of detection is the number of successful detections
    divided by the total number of tests of the type being considered. Note
    that these point estimates are different from the lower 95% confidence
    limits discussed previously. The benefit of computing point estimates
    for each method of approach in each segment is to recognize a segment
    that may be particularly vulnerable to a specific method of approach.
    The concept is to look for trends occurring in the data. For example,
    if all or most of the failures to detect in a segment are in one method
    of approach, this segment should be suspected as being vulnerable to
    this method of approach. As a specific example, let the initial 30
    tests be 6 tests each of running, walking, crawling, jumping, and
    rolling. Assume that no failures to detect intrusion occurred. The
    point estimate for the overall probability of detection is 30/30 = 100%;
    the point estimate for the probability of detection for a crawling
    approach is 6/6 = 100%. Let the subsequent quarterly tests be two tests
    each of the five methods of approach. In the next three quarters,
    assume that one failure to detect occurred in a crawling approach.
    Table 7 below gives the point estimates for the overall probability of
    detection and for the crawling approach.
    Note that the minimum number of successful detections are achieved
    for the total number of tests and 9 successful detections are achieved
    for the 10 quarterly tests. However, by computing the point estimates
    for each method of approach the trend can be seen that a crawling
    approach has a fairly high likelihood of not being detected. Additional
    testing should be performed to verify that the particular approach is a
    system weakness, not random failures that coincidentally occurred in the
    same method of approach. If the weakness is verified, it should be
    eliminated, perhaps by increasing the sensitivity of the detector or by
    installing an additional device to detect this type of approach with a
    higher probability. If, on the other hand, the failures of detection
    come from varying approaches and if the overall probability of detection
    in the segment is sufficiently high, i.e., the maximum number of
    failures to detect for the total number of tests is not exceeded, no
    specific weakness is indicated for this segment.
    Caution: When the data indicate a problem with the detection system
    and the problem is corrected, do not combine (sum) the next
    quarter's data with the data from previous quarters for the
    problem segment. Begin accumulating the data again for this
    segment, starting with the 30 tests from the current
    quarter's testing that were conducted after correcting the
    problem.
    A table similar to Table 5 can be used for recording and reporting
    the test results for each method of approach, each segment, and each
    quarter. The date and time of day and relevant environmental conditions
    such as weather, microwave field intensity, E-field intensity, and
    changes in light level should be recorded.
    APPENDIX B(*)CALCULATING THE CONFIDENCE LIMIT ON THE DETECTION PROBABILITY
    Assume a binomial model for the number of successful detections,
    i.e., the probability of a successful detection is a fixed value,
    designated "p", and the tests for detection are independent. Let the
    number of tests performed be "n" and the number of successful detections
    "x".
    The point estimate of p, @@, is x/n.
    However, the problem is to obtain a confidence interval for p,
    which in this case is a lower one-sided 95% confidence limit.
    The normal approximation to the binomial distribution is a valid
    approximation only when n@@ and n(1 - @@) are both equal to or greater
    than 5. For example, for the performance criterion of 48 successes out
    of 50 tests, n(1 - @@) equals 2. Also, when there are no failures in
    detection, it is not possible to use the normal approximation since
    var(@@) = n@@(1 - @@) = 0.
    The exact lower 95% confidence limit on p is given by
    (Due to database constraints, this equation is not included. Please
    contact LIS to obtain a copy.)where F(05)(a,b) is the value of the F distribution with "a" and "b"
    degrees of freedom which leaves 5% in the upper tail of the
    distribution.
    Three examples given in Appendix A to this guide can be derived as
    follows:
1. For x = 48 successes and n = 50 tests,
    (Due to database constraints, this equation is not included. Please
    contact LIS to obtain a copy.) using F(.05)(6,96) @@ 2.19.
    ----------
    (*) Although this appendix is a substantive addition to Revision
    2, no lines are added in the margin.
    ----------
2. For x = 95 successes and n = 100 tests,
    (Due to database constraints, this equation is not included. Please
    contact LIS to obtain a copy.)3. For x = 98 successes and n = 100 tests,
    (Due to database constraints, this equation is not included. Please
    contact LIS to obtain a copy.) using F(.05)(6,196) @@ 2.14.
    Table 1 gives the lower 95% confidence limits for the probability
    of detection for n = 30, 40, 50, 60, 70, 80, and 90 beginning with x
    values such that the lower confidence limit is approximately equal to
    88%; and for n = 100, 110, and 120 beginning with x values such that the
    lower confidence limit is approximately equal to 90%. The lower
    confidence limits for n = 30, 40, and 50 were abstracted from
    "Percentage Points of the Incomplete Beta Function," Robert E. Clark,
    Journal of the American Statistical Association 48: 831-843 (1953).
    The lower confidence limits for n = 60, 70, 80, 90, and 100 were
    abstracted from "Tables of Confidence Limits for the Binomial
    Distribution," James Pachares, Journal of the American Statistical
    Association 55: 521-533 (1960). The lower confidence limits for n =
    110 and 120 were computed using Formula (1).
    Clark's article gives confidence limits for all values of n from
    10 to 50 for all values of x from 1 to n. Pachares' article gives
    confidence limits for values of n from 55 to 100 in increments of 5 for
    all values of x from 1 to n. The confidence limits for any values of n
    and x can be computed using Formula (1).
    (Due to database constraints, Table 1 is not included. Please contact
    LIS to obtain a copy.)
    48