Title: Walk-Through Metal Detectors for Use in Concealed Weapon and
Contraband Detection: NIJ Standard-0601.02
Series: NIJ Standard
Author: Nicholas G. Paulter, Jr.
Published: National Institute of Justice, January 2003
Subject: Technology in law enforcement and crime prevention
46 pages
84,000 bytes

------------------------------

Figures, charts, forms, and tables are not included in this ASCII plain-text
file. To view this document in its entirety, download the Adobe Acrobat
graphic file available from this Web site or order a print copy from
NCJRS at 800-851-3420 (877-712-9279 for TTY users).

------------------------------

U.S. Department of Justice
Office of Justice Programs
National Institute of Justice

National Institute of Justice
Law Enforcement and Corrections Standards and Testing Program

Walk-Through Metal Detectors for Use in Concealed Weapon and
Contraband Detection

NIJ Standard 0601.02

------------------------------

U.S. Department of Justice
Office of Justice Programs
810 Seventh Street N.W.
Washington, DC 20531

John Ashcroft
Attorney General

Deborah J. Daniels
Assistant Attorney General

Sarah V. Hart
Director, National Institute of Justice

For grant and funding information, contact:

Department of Justice Response Center
800-421-6770

Office of Justice Programs
World Wide Web Site:
http://www.ojp.usdoj.gov

National Institute of Justice
World Wide Web Site:
http://www.ojp.usdoj.gov/nij

Walk-Through Metal Detectors for Use in Concealed Weapon and
Contraband Detection

NIJ Standard-0601.02
Supersedes NIJ Standard-0601.01 dated September 2000
Supersedes NILECJ-STD-0601.00 dated October 1974

Nicholas G. Paulter, Jr.
Electricity Division
National Institute of Standards and Technology
Gaithersburg, MD 20899

Prepared for:
National Institute of Justice
Office of Science and Technology
Washington, DC 20531

January 2003

NCJ 193510

------------------------------

National Institute of Justice
Sarah V. Hart
Director

This standard was prepared for the National Institute of Justice, U.S.
Department of Justice, by the Office of Law Enforcement Standards of the
National Institute of Standards and Technology under Interagency
Agreement 99-IJ-R-094, Project No. 02-002.

The NIJ Standard-0601.02, "Walk-Through Metal Detectors for Use in
Concealed Weapon and Contraband Detection," is a revision to and
supersedes the NIJ Standard-0601.01 published in September 2000. The
2000 revision addressed concerns of the criminal justice and public safety
communities for an updated performance standard based on current
technologies and responded to recommendations from the Law
Enforcement and Corrections Technology Advisory Council. This current
revision responds to comments received from industry and the criminal
justice and public safety communities on the 2000 revision.

K.D. Rice of the Office of Law Enforcement Standards (OLES) of NIST
and D.R. Larson of NIST are acknowledged for their comments and
recommendations.

------------------------------

FOREWORD

The Office of Law Enforcement Standards (OLES) of the National
Institute of Standards and Technology (NIST) provides technical support
to the National Institute of Justice (NIJ) program to support law
enforcement and criminal justice in the United States. OLES's function is to
develop standards and conduct research that will assist law enforcement
and criminal justice agencies.

OLES is: (1) subjecting existing equipment to laboratory testing and
evaluation, and (2) conducting research leading to the development of
several series of documents, including national standards, user guides, and
technical reports.

This document covers research conducted by OLES under the sponsorship
of NIJ. Additional reports as well as other documents are being issued
under the OLES program in the areas of protective clothing and
equipment, communications systems, emergency equipment, investigative
aids, security systems, vehicles, weapons, and analytical techniques and
standard reference materials used by the forensic community.

Technical comments and suggestions about this guide are welcome and
may be addressed to the Office of Law Enforcement Standards, National
Institute of Standards and Technology, 100 Bureau Drive, Stop 8102,
Gaithersburg, MD 20899-8102.

Sarah V. Hart, Director
National Institute of Justice

------------------------------

CONTENTS

FOREWORD

COMMONLY USED SYMBOLS AND ABBREVIATIONS

1. INTRODUCTION
--1.1 Purpose of the Standard
--1.2 Definitions

2. REQUIREMENTS FOR ACCEPTANCE
--2.1 Safety Specifications and Requirements
--2.2 Electrical Requirements
--2.3 Detection Performance Specifications
--2.4 Operating Requirements
--2.5 Mechanical Specifications and Requirements
--2.6 Functional Requirements
--2.7 Detector Mount
--2.8 Quality Control and Assurance
--2.9 Documentation

3. PERFORMANCE TESTING PROCEDURES
--3.1 General Test Conditions
--3.2 Detection Performance Tests
--3.3 Alarm Indication Test
--3.4 Test for Operation Near a Metal Wall, Steel Reinforced Floor, or
Moving Metal Door
--3.5 Burn-In Test

4. FIELD TESTING PROCEDURES
--4.1 Large Object Size
--4.2 Medium Object Size
--4.3 Small Object Size

5. TEST OBJECTS DESCRIPTION
--5.1 Large Object Size Test Objects
--5.2 Medium Object Size Test Objects
--5.3 Small Object Size Test Objects
--5.4 Innocuous Item Test Objects

6 . COMPLIANCE TEST REPORT FORM

7. REFERENCES

------------------------------

FIGURES

Figure 1. Diagram of walk-through metal detector showing the detector
plane, the detector axis, and the x, y, and z axes of the measurement
coordinate system

Figure 2. Diagram showing the detector and the detector mount, the
detector plane, the detector floor, and the reference surface

Figure 3. Diagram illustrating the nine test measurement locations
positioned in relation to the x and z axes of the measurement coordinate
system

Figure 4. Test measurement locations for detection performance tests
where the outer box represents the inside dimensions of the walk-through
metal detector

Figure 5. Drawing of the detector mount showing the positioning of
grooves for the steel reinforced floor test

Figure 6. Mechanical drawing of the reference surface

Figure 7. Drawing of assembly of items A, B, and C of test-object
support platform

Figure 8. Drawing of assembly of items D and E of test-object support
platform

------------------------------

COMMONLY USED SYMBOLS AND ABBREVIATIONS

A--ampere
ac--alternating current
AM--amplitude modulation
cd--candela
cm--centimeter
CP--chemically pure
c/s--cycle per second
d--day
dB--decibel
dc--direct current

[degrees]C--degree Celsius
[degrees]F--degree Fahrenheit
dia--diameter
emf--electromotive force
eq--equation
F--farad
fc--footcandle
fig.--figure
FM--frequency modulation
ft--foot
ft/s--foot per second
g--acceleration
g--gram
gr--grain
H--henry
h--hour
hf--high frequency
Hz--hertz (c/s)
i.d.--inside diameter
in--inch
IR--infrared
J--joule
L-lambert
L-liter
lb--pound
lbf--pound-force
lbf in--pound-force inch
lm--lumen
ln--logarithm (base e)
log--logarithm (base 10)
M--molar
m--meter
min--minute
mm--millimeter
mph--miles per hour
m/s--meter per second
N--newton
N m--newton meter
nm--nanometer
No.--number
o.d.--outside diameter
[omega]--ohm
p.--page
Pa--pascal
pe--probable error
pp.--pages
ppm--parts per million
qt--quart
rad--radian
rf--radio frequency
rh--relative humidity
s--second
SD--standard deviation
sec.--section
SWR--standing wave ratio
uhf--ultrahigh frequency
UV--ultraviolet
V--volt
vhf--very high frequency
W--watt
[lambda]--wavelength
wt--weight

area=unit[2] (e.g., ft[2], in[2], etc.); volume=unit[3] (e.g., ft[3], m[3], etc.)

PREFIXES

d--deci (10[-1])
c--centi (10[-2])
m--milli (10[-3])
[mu]--micro (10[-6])
n--nano (10[-9])
p--pico (10[-12])
da--deka (10)
h--hecto (10[2])
k--kilo (10[3])
M--mega (10[6])
G--giga (10[9])
T--tera (10[12])

COMMON CONVERSIONS (See ASTM E380)

0.30480 m =1ft
25.4 mm = 1 in
0.4535924 kg = 1 lb
0.06479891g = 1gr
0.9463529 L = 1 qt
3600000 J = 1 kW hr
4.448222 N = 1 lbf
1.355818 J = 1 ft lbf

0.1129848 N m = 1 lbf in
14.59390 N/m = 1 lbf/ft
6894.757 Pa = 1 lbf/in[2]
1.609344 km/h = 1 mph

Temperature: T [degrees]C = (T [degrees]F 32)x5/9

Temperature: T [degrees]F = (T [degrees]C 9/5)+32

------------------------------

NIJ Standard-0601.02

NIJ STANDARD FOR WALK-THROUGH METAL DETECTORS FOR
USE IN CONCEALED WEAPON AND CONTRABAND DETECTION

1. INTRODUCTION

1.1 Purpose of the Standard

The purpose of this document is to establish performance requirements and
testing methods for active walk-through metal detectors used to find metal
weapons and/or metal contraband carried on a person and/or concealed by
a nonmetal object.

1.2 Definitions

The definitions are provided to help the reader use and understand this
document, which describes methods for evaluating active walk-through
metal detectors used as weapons detectors. Terms that are defined here
appear in italics in the remainder of this document.

All measurement units used in this document are metric. Length units are
abbreviated: meter (m), centimeter (cm), and millimeter (mm). Where
useful, English units are indicated in parentheses immediately following the
metric units, such as "2.54 cm (1 in)."

1.2.1 Alarm Indication

A signal to warn of the detection of a metal object. The indication can be
visual and/or auditory.

1.2.1.1 Positive Alarm Indication

The change in the alarm indication that corresponds to the detection of a
metal object. Typically, the alarm indication is off until a metal object is
detected.

1.2.1.2 Proportional Alarm Indication

An alarm indication proportional to the size, proximity, orientation, and
material of an object.

1.2.2 Alarm Indicator

The device used to generate the alarm indication. For a visual indication,
the alarm generating device can be a light bulb, lamp, light emitting diode,
etc. For an auditory indication, the alarm generating device can be a horn,
siren, buzzer, or similar item.

1.2.3 Active Detector

An active detector is generally a device that generates energy for
illuminating the portal region of the detector. For the walk-through metal
detector, the generated energy is in the form of a magnetic field. The
interaction of the generated magnetic field with certain types of objects in
the portal region of the detector and the ability to detect this interaction is
the basis of operation for walk-through metal detectors.

1.2.4 Clean Tester

A person who does not carry any electrically conductive and magnetizable
objects such as metallic belt buckles, metal buttons, cardiac pacemaker,
coins, metal-frame eyeglasses, hearing aid, jewelry, keys, pens and pencils,
shoes with metal arches or supports, metallic surgical implants,
undergarment support metal, metal zippers, and similar items, which would
significantly alter the signal produced when the person carries a test object.

1.2.5 Detection

The discovery or finding of a metallic object. The detection of a metallic
object is transmitted to the operator by some type of alarm indicator,
typically a visual or audible indicator.

1.2.6 Detector Axis

An imaginary line passing through and perpendicular to the detector plane
that is centered vertically and horizontally within the portal of the
walk-through metal detector and points in the direction of the subject's
motion through the portal. See figure 1.

1.2.7 Detector Floor

The bottom plane of the detector portal.

1.2.8 Detector Mount

A nonconductive, nonmagnetic platform on which the walk-through metal
detector rests. The detector mount locates the detector floor at a height of
32.5 cm (12.8 in) and contains grooves at 10 cm (4 in) below its top
surface to facilitate the metal floor test required under section 3.4.2. The
reference surface of the detector mount is parallel to the detector plane,
contains tapped holes that mate to the mounting holes of the positioning
system (see sec. 3.2.2.2), and holds the detector plane 0.5 m (1.7 ft) from
the reference surface. The detector mount is supplied by the manufacturer
and attached to the detector positioner at their reference surfaces. See
figure 2.

1.2.9 Detector Plane

An imaginary plane (two-dimensional surface) that is parallel to the portal
of the walk-through metal detector and that bisects the sensor region into
two symmetric halves. The detector plane contains two orthogonal axes
labeled the "x" axis and the "z" axis. See figure 1.

1.2.10 Detector Positioner

A nonconductive, nonmagnetic device that fixes the position of the
detector plane and detector axis with respect to the three-axes translation
system. The detector positioner includes a reference surface for attaching
the detector mount. The detector positioner also includes a surface for
attachment to the three-axes translation system.

1.2.11 Detector Response

The electrical signal generated by the sensor or sensor circuit of the
detector and caused by an object interacting with the magnetic field
generated by the detector. The detector response is the basis on which an
alarm indication is derived.

1.2.12 Ground Surface

The surface on which the walk-through detector rests.

1.2.13 Measurement Coordinate System

A mutually orthogonal three-dimensional Cartesian coordinate system
referenced to the detector axis and the detector plane. The three axes are
labeled "x," "y," and "z," where the y axis is parallel to the detector axis
and the x and z axes are in the detector plane. The orientation of the test
objects and direction of the magnetic field is referenced to the measurement
coordinate system. See figure 1.

1.2.14 Object Size Classes

A classification method based on the ability to detect metal objects of a
minimum size. A detector may meet the requirements for one, two, or three
object size classes, as defined below.

1.2.14.1 Large Object Size

The ability to detect handguns concealed on an individual that are
constructed of either ferromagnetic or nonferromagnetic metal.

1.2.14.2 Medium Object Size

The ability to detect knives on an individual that are constructed of either
ferromagnetic or nonferromagnetic metal. Large knives are defined for this
purpose as knives with blade lengths exceeding 7.5 cm (3 in).

1.2.14.3 Small Object Size

The ability to detect small weapons and contraband items concealed on an
individual that are constructed of either ferromagnetic or nonferromagnetic
metal. Small weapons and contraband items are defined as items that can
be used to injure another person or to defeat security devices.

1.2.15 Reference Surface

The planes located on the detector mount and detector positioner used to
attach the detector mount and detector positioner. See figure 2.

1.2.16 Specific Test Measurement Location

The nine positions in the x-z plane (the x-z plane is parallel to the detector
plane) through which the test object(s) shall be passed. The test
measurement locations are based on the size of the average male person
and are defined at points along the x and z axes of the measurement
coordinate system. There are two locations at ankle height separated
approximately by hip width, two at hip height separated approximately by
hip width, two at shoulder height separated approximately by torso width,
one at top of head height centered along the z axis, one at slightly below
armpit height centered along the z axis, and one at crotch height centered
along the z axis. See figure 3.

1.2.17 Test Object

An item used to test the walk-through detection performance. The test
object is an encased replica of a metallic item that is either a weapon, can
be used as a weapon, or can be used to defeat security devices. The shape
of the encasement is a parallelepiped. The encasement has up to 12 holes
that allow the replica to be oriented with respect to the measurement
coordinate system; no more than nine possible orientations are allowed,
one to three orientations for each unique orthogonal surface, but no more
than three, of the parallelepiped.

1.2.17.1 Large Object Size Test Objects

Test objects that are used to test the large object size detection
performance of walk-through metal detectors used as weapon detectors.
Mechanical drawings of the large object size test objects are provided in
section 5.1.

1.2.17.2 Medium Object Size Test Objects

Test objects that are used to test the medium object size detection
performance of walk-through metal detectors used as weapon detectors.
Mechanical drawings of the medium object size test objects are provided in
section 5.2.

1.2.17.3 Small Object Size Test Objects

Test objects that are used to test the small object size detection
performance of walk-through metal detectors used as weapon detectors.
Mechanical drawings of the small object size test objects are provided in
section 5.3.

1.2.17.4 Innocuous Item Test Objects

Test objects that are used to test the discrimination performance of the
large object size and medium object size walk-through metal detectors.
Mechanical drawings of the innocuous item test objects are provided in
section 5.4.

1.2.18 Test Object Axes

The three mutually orthogonal axes of the test object that are referenced to
and have a one-to-one correspondence to the axes of the measurement
coordinate system.

1.2.19 Test Measurement Grid Location

The positions in the x-z plane (the x-z plane is parallel to the detector
plane) through which the test object(s) shall be passed. The test
measurement grid locations are located within the rectangular region
bounded by the extrema of the specific test measurement locations ([plus
or minus] 20 cm [plus or minus] 0.1 cm for the x axis and 5 cm and 180 cm
for the z axis) and are located on a 5 cm [plus or minus] 0.1 cm by 5 cm
[plus or minus] 0.1 cm grid.

1.2.20 Three-Axes Positioning System

Also known as a Cartesian robot, the three-axes positioning system
provides three mutually orthogonal directions of linear translation. The
three-axes positioning system is used to place test objects in the magnetic
field of the detector.

2. REQUIREMENTS FOR ACCEPTANCE

The detector shall meet the requirements and specifications stated in this
section. Reports shall be provided on the Compliance Test Report forms
mentioned in section 6.

2.1 Safety Specifications and Requirements

2.1.1 Electrical

The detector shall comply with UL 60950, Safety for Information
Technology Equipment, if the electrical potential difference between any
two points within the detector is greater than 30 V rms (42.4 V peak-to-
peak) for alternating currents (ac) or greater than 60 V referenced to
ground for direct currents (dc).

2.1.2 Mechanical

The detector shall not expose (1) any sharp corners or edges that can
puncture, cut, or tear the skin or clothing or injure persons coming in
contact with the detector, (2) external wires, connectors, and cables,
except the power cable described in section 2.2.2, or (3) loose covers and
cowlings. The minimum exposed radius of curvature for corners and edges
shall be 1 mm (0.04 in).

2.1.3 Exposure

The level of the magnetic field generated by the detector shall be less than
the exposure limits specified in ACGIH-0302 (1996), Sub-Radio
Frequency (30 kHz and below) Magnetic Fields, as amended.

2.1.4 Personal Medical Electronic Devices

The magnetic fields produced by the detector shall not generate voltages
across the leads of the test probe specified in Safety Code, Recommended
Safety Procedures for the Selection, Installation and Use of Active Metal
Detectors (the Safety Procedures), Radiation Protection Bureau, Canadian
Minister of National Health and Welfare that exceed the maximum
permitted probe output specified in the Safety Procedures when tested in
accordance to the Safety Procedures.

2.2 Electrical Requirements

2.2.1 AC Power

The detector shall operate at the available power line voltages with
variations in line voltage less than or equal [plus or minus] 10 % of the
nominal value and with variations in frequency [less than or equal to] [plus
or minus] 5 % of the nominal value. The manufacturer shall provide an
indicator to alert the operator of the ac power status, if outside of range, as
described in section 2.6.2.5.

2.2.2 AC Connector

An ac power connector socket shall be provided on both sides of the
detector portal unless the operation and function of the detector is the same
for traffic flow in both directions, in which case an ac connector is required
on one side of the portal. To provide a secure connection, the ac connector
socket shall not be exposed.

2.3 Detection Performance Specifications

The detection performance specifications shall be tested using the specific
set of detector program parameter settings that is specified by the
manufacturer to be appropriate for each object size class of detector that is
to be tested.

2.3.1 Detection Sensitivity

The detector response shall be measured at all specific test measurement
locations and test measurement grid locations and shall provide a positive
alarm indication for each test object of the appropriate object size class for
each allowed orientation of the test object axes with respect to the
measurement coordinate system moving at a speed of 1.0 m/s [plus or
minus] 0.05 m/s in accordance with section 3.2.3. The results shall be
recorded and a report shall be provided. The test object, the orientation of
the test object axes of this test object with respect to the measurement
coordinate system, and the test measurement location (see fig. 4) of this
test object that provide a minimum detector response for the appropriate
object size class shall be recorded and specified as the "minimum detection
conditions." The test object, the orientation of the test object axes of this
test object with respect to the measurement coordinate system, and the x-
and y-axes scan positions (see sec. 3.2.3) of the test measurement grid
locations that provide a minimum detector response for the appropriate
object size class shall be recorded and specified as the "alternate minimum
detection conditions." If more than one x-z position can satisfy the
requirements of the minimum detection condition or the alternate minimum
detection condition, then one position shall be selected for each condition.

2.3.2 Speed

The detector shall provide a positive alarm indication for the "minimum
detection conditions" and "alternate minimum detection conditions" for
each appropriate object size class as determined according to section 2.3.1
for the test object moving at the following speeds: 0.2 m/s [plus or minus]
0.01 m/s, 0.5 m/s [plus or minus] 0.01 m/s, 1.0 m/s [plus or minus] 0.01
m/s, and 2.0 m/s [plus or minus] 0.01 m/s as tested in accordance with
section 3.2.4. The results shall be recorded.

2.3.3 Repeatability

The detector shall provide a positive alarm indication without failure for
the "minimum detection conditions" and "alternate minimum detection
conditions" for each appropriate object size class as determined according
to section 2.3.1 for the test object moving at a speed of 1.0 m/s [plus or
minus] 0.05 m/s for 50 consecutive trials under the following conditions:

a. The delay between subsequent trials of a given test object shall be no
more than 5 s.

b. The detector sensitivity shall not be readjusted between trials of a given
test object or between trials of the test objects of a given object size class.

This test shall be performed according to section 3.2.4, and the results shall
be recorded. The results of this test can also be called the probability of
detection, p[d], with a required p[d] of 1.00 (or 100 %).

2.3.4 Discrimination

The detector shall meet the requirements of section 2.3.1 and without
readjustment shall not provide a positive alarm indication for at least 20 of
25 consecutive trials when tested in accordance with section 3.2.5 for the
innocuous item test objects moving at a speed of 1.0 m/s [plus or minus]
0.1 m/s, and the results shall be recorded. The results of this test can also
be called the probability of false alarm, p[fa], with a required p[fa] of less
than 0.2 (or 20 %).

2.3.5 Throughput Rate

The detector shall provide a positive alarm indication for the test object of
the appropriate object size class and its orientation from which the
"minimum detection conditions" were determined (see sec. 2.3.1) for the
test object moving at a speed of 1 m/s [plus or minus] 0.05 m/s at the
z-axis positions of 86 cm [plus or minus] 0.5 cm, 144 cm [plus or minus]
0.5 cm, and 178 cm [plus or minus] 0.5 cm when tested in accordance with
section 3.2.7, and the results shall be recorded.

2.4 Operating Requirements

2.4.1 Operator Controls

Only those controls required to operate the equipment shall be accessible to
the operator. Other controls and adjustments that affect the detector
performance shall be inaccessible to the operator. The detector shall be
self-testing upon turn-on without any adjustment required by the operator
and shall be continuously self-testing during the period of operation with
automatic self-adjusting, if required. The following operator controls shall
be provided:

2.4.1.1 Power On/Off Switch

The detector shall have a power on/off switch.

2.4.1.2 Audio Alarm On/Off Switch

The detector shall have a means for selectively disabling the audio alarm.

2.4.1.3 Detector Reset Button

The detector shall reset automatically to the set program parameters in the
event of a detector or system failure or overload. There shall be a detector
reset button to reset the detector such that program parameters are not
affected if the automatic reset for a detector overload condition is not
functioning properly.

2.4.1.4 Detector Sensitivity Programming

If provided, the detector sensitivity shall be programmed electronically, and
if the detector is designed for multiple object size classes, then it shall have
settings that correspond to the appropriate object size classes.

2.4.2 Interference

2.4.2.1 Electromagnetic

2.4.2.1.1 Emission

The detector, when adjusted to meet the requirements of section 2.3.3,
shall meet the requirements of EN 50081-1, as amended.

2.4.2.1.2 Susceptibility/Immunity

2.4.2.1.2.1 General Immunity Requirements

The detector, when adjusted to meet the requirements of section 2.3.3,
shall not provide a positive alarm indication when tested in accordance with
EN 50082-1, as amended.

2.4.2.1.2.2 Radiated Magnetic Field

The detector, when adjusted to meet the requirements of section 2.3.3,
shall not provide a positive alarm indication when tested in accordance with
MIL-STD-461E, Method RS101, as amended, to the limits for Navy
applications.

2.4.2.2 Metallic Interference

2.4.2.2.1 Stationary Objects

The detector, when adjusted to meet the requirements of section 2.3.3 and
tested in accordance with sections 3.4.1 and 3.4.2, shall not produce a
positive alarm indication when no test object is presented to the detector.

2.4.2.2.2 Moving Objects, Moving Metal Door

The detector shall not produce a positive alarm indication when operated
near a moving metal door, as tested in accordance with section 3.4.3, but
shall produce a positive alarm indication for each appropriate test object
and its orientation providing a minimum response as determined according
to section 2.3.1 for the test object moving at a speed of 1.0 m/s [plus or
minus] 0.05 m/s at each test measurement location when operated while
such a door is moving in accordance with section 3.4.3.

2.4.2.3 Body Interference

The detector, when adjusted to meet the requirements of section 2.3.3,
shall not produce a positive alarm indication when tested in accordance
with section 3.2.6; the results shall be recorded and a report provided.

2.4.2.4 Multiple Object Interference (Large Object Size Class Only)

The detector shall produce a positive alarm indication when tested in
accordance with section 3.2.8; the results shall be recorded and a report
provided.

2.4.3 Environmental Ranges and Conditions

The detector or all of its components and their interconnections shall meet
the requirements of all of the following standards. The requirements of
section 2.1 and section 2.5 shall not be affected by the tests described in
this section. The requirements given in this section shall be applied
appropriately for either indoor, sheltered outdoor, or outdoor detector
models. The requirements of this section shall be exhibited by no less than
the first production unit for each unique detector model and for any
physical modifications to that model. The tests listed in section 2.4.3 shall
be performed on the same unit. The detector, if tested for any of the tests
listed in section 2.4.3, shall exhibit no observable changes in the detection
performance specification given in section 2.3.3.

2.4.3.1 Temperature Stability and Range

2.4.3.1.1 Indoor, Sheltered Outdoor

The detector shall operate over the ambient temperature range of at least 0
[degrees]C to 46 [degrees]C (32 [degrees]F to 115 [degrees]F). The
detector shall be tested in accordance with MIL-STD-810F Method 501.4,
Procedure II, at 46 [degrees]C [plus or minus] 3 [degrees]C after being
exposed to that temperature continuously for 24 h [plus or minus] 1 h. The
detector then shall be cooled to 0 [degrees]C [plus or minus] 3 [degrees]C
within 4 h [plus or minus] 0.5 h and tested in accordance with
MIL-STD-810F Method 502.4, Procedure II, at 0 [degrees]C [plus or
minus] 3 [degrees]C after being exposed to that temperature continuously
for 24 h [plus or minus] 1 h.

2.4.3.1.2 Outdoor

The detector shall operate over the ambient temperature range of at least
-37 [degrees]C to 65 [degrees]C (-35 [degrees]F to 149 [degrees]F). The
detector shall be tested in accordance with MIL-STD-810F Method 501.4,
Procedure II, at 65 [degrees]C [plus or minus] 3 [degrees]C after being
exposed to that temperature continuously for 24 h [plus or minus] 1 h. The
detector then shall be cooled to -37 [degrees]C [plus or minus] 3
[degrees]C within 4 h [plus or minus] 0.5 h and tested in accordance with
MIL-STD-810F Method 502.4, Procedure II, at -37 [degrees]C [plus or
minus] 3 [degrees]C after being exposed to that temperature continuously
for 24 h [plus or minus] 1 h.

2.4.3.2 Relative Humidity Stability and Range

The detector shall be tested in accordance with the requirements of MIL-
STD-810F Method 507.4, as amended.

2.4.3.3 Salt Fog, Sheltered Outdoor and Outdoor

The detector shall be tested in accordance with the requirements of MIL-
STD-810F Method 509.4, as amended.

2.4.3.4 Environmental Protection

2.4.3.4.1 Indoor

The detector shall meet or exceed the requirements for compliance to IEC
60529 classification IP41.

2.4.3.4.2 Sheltered Outdoor

The detector shall meet or exceed the requirements for compliance to IEC
60529 classification IP53.

2.4.3.4.3 Outdoor

The detector shall meet or exceed the requirements for compliance to IEC
60529 classification IP55.

2.4.3.5 Solar Radiation (Sunshine), Outdoor Only

The detector shall be tested in accordance with and meet the requirements
of MIL-STD-810F Method 505.4, Procedure 1, as amended.

2.5 Mechanical Specifications and Requirements

2.5.1 Dimensions and Weight

The detector shall be designed so the interior of the portal through which
people will walk has the following dimensions:

a. Height, minimum: 195 cm (77 in).

b. Width, minimum: 71 cm (28 in) unless required to comply with that
specified by the American Disabilities Act.

c. Depth, maximum: 91 cm (36 in).

The detector shall have a mass of less than 100 kg (220 lb).

2.5.2 Durability/Ruggedness

The detector or all of its components and their interconnections shall meet
the requirements of the following standards. The requirements of section
2.1 and section 2.4 shall not be affected by the tests described in this
section. The tests listed in section 2.5.2 shall be performed on the same
unit.

2.5.2.1 Impact Resistance

The detector, if tested for any of the tests listed in section 2.5.2.1, shall
exhibit no observable changes in the detection performance specification
given in section 2.3.3.

2.5.2.1.1 Shock

The detector shall be tested in accordance with the requirements of IEC
68-2-27 1987, as amended, using the half-sine pulse shape with a nominal
peak acceleration of 5 g (50 m/s[2]) and nominal pulse duration of 30 ms.

2.5.2.1.2 Bump

The detector shall be disassembled and the control unit and columns of the
detector shall be tested independently and in accordance with the
requirements of IEC 68-2-29 1987, as amended, using 100 bumps each
with a nominal peak acceleration of 10 g (100 m/s[2]) and nominal pulse
duration of 16 ms.

2.5.2.2 Pressure Resistance

The detector should be capable of being secured in place to prevent being
tipped over or slipping as a result of casual bumping or pushing. The
detector shall be capable of withstanding the forces described below.

2.5.2.2.1 Slide

A force shall be applied at 1.0 m [plus or minus] 0.1 m (39 in [plus or
minus] 4 in) above the ground surface in the direction of passage until the
detector starts to slide. The detector shall be capable of withstanding the
force of 200 N (45 lb) without sliding.

2.5.2.2.2 Tip-Over

The detector shall be tested in accordance with section 5.4 of American
Society for Testing and Materials (ASTM) Designation F 1468-95, as
amended. The test results shall be recorded and a report provided. The
detector shall be capable of withstanding a force of 600 N (135 lb) applied
to the detector at 1.3 m [plus or minus] 0.1 m (51 in [plus or minus] 4 in)
above the ground surface in the direction of passage without tipping.

2.6 Functional Requirements

2.6.1 Program Storage

The detector shall have a means of storing the program and detection
sensitivity settings in the event of loss or disruption of ac power to
maintain the calibration and setup of the walk-through metal detector
parameters.

2.6.2 Alarm Indicators

2.6.2.1 Audible Alarm Indicators

All audible indicators (other than an earphone) shall produce an alarm-state
sound pressure level 0.8 m [plus or minus] 0.08 m from the detector of
85dB[SPL] [plus or minus] 5 dB[SPL] measured in accordance with
section 3.3.2. For status indicators, the audible alarm shall be a two-state
audible alarm: active (alarm state) and inactive (nonalarm state). The
two-state alarm indicator shall produce no sound in the nonalarm state.

2.6.2.2 Earphone Jack, Optional

If an earphone jack is supplied with the walk-through metal detector, the
earphone shall disable the audible alarm indicator when the earphone is
plugged into the earphone jack.

2.6.2.3 Visual Alarm Indicators

Any visible alarm indication shall be readily perceptible when tested in
accordance with section 3.3.3. The visual alarm indicators shall be a two-
state visual alarm: active (illuminating) and inactive (nonilluminating).

2.6.2.4 Metal Object Detection

The detector shall have a two-state audible alarm indicator and a visual
alarm indicator which shall alarm to indicate the presence of a test object in
the portal region. The alarm state for the metal-object-detection visual
alarm indicator shall be active (illuminating), and the nonalarm state shall
be inactive (nonilluminating). The metal-object-detection visual alarm
indicator shall be distinct from any other visual alarm indicators.

2.6.2.5 AC Power Out-of-Range Condition

The detector shall have a two-state audible alarm indicator to indicate the
ac power level is out of specification and shall be activated if the state of
the ac power changes to a level that can cause an observable change in
detection performance specifications.

2.6.2.6 System Status

The detector shall have a two-state audible alarm indicator or a visual
alarm indicator to indicate the operational state of the detector system and
shall be activated if the operational state of the detector can cause a
degradation of the detection performance required by this standard. The
system status visual alarm indicator shall be inactive (nonilluminating) if the
system status is acceptable and shall be active (illuminating) if a system
status problem exists. The system status visual alarm indicator shall be
distinct from any other visual alarm indicators.

2.6.2.7 Detection Ready State Violation

The detector shall have a two-state audible alarm indicator or a visual
alarm indicator to indicate passage of a person through the detector when it
was not in the ready state as described in section 2.6.2.8 and shall be
activated if a person attempts to pass through the detector when it is not in
the ready state. The visual alarm indicator shall be active (illuminating) if a
person attempts to pass through the detector when it is not in the ready
state, and inactive (nonilluminating) otherwise.

2.6.2.8 Detection Ready State (Stop/Go)

The detector shall have clearly visible to the approaching traffic, a visual
indicator showing the ready state of the detector; that is, whether the
detector is ready to allow a pass through or not. The ready state shall be
indicated by a green and red visual indicator; the green visual indicator shall
denote readiness, and the red visual indicator shall denote lack of readiness.
The green light (or "Go" light) shall indicate that the detector is ready for a
person to enter and pass through the detector, and the red light (or "Stop"
light) shall indicate that the detector is not ready for a person to enter the
detector.

2.6.3 Detection Signal Output Connector

The detector shall have an electrical connector from which either an analog
or digital output signal is obtained. This signal represents the magnitude of
the detector's response to an object and is the detector signal upon which
an alarm indication is based. If the output signal is analog, the connector
shall be coaxial where the inner conductor provides the signal path and the
outer conductor of the connector provides signal ground or return. For
detectors consisting of more than one generator and/or sensor, such as in
multizone detectors, there shall be a detection signal output connector for
each sensor or sensor circuit unless the sensor or sensor circuit outputs are
multiplexed together. If the sensor circuits of a multizone system are
multiplexed, the detection signal output connector can be used to monitor
the output of each sensor or sensor circuit.

2.6.4 Interchangeability

Any model detector manufactured by the same manufacturer shall be
compatible with previous revisions of the same model (backwardly
compatible). In particular, the following components shall be backwardly
compatible:

a. Replacement parts.

b. Error codes.

c. Program codes.

d. Diagnostic warnings.

e. Connectors.

2.6.5 Field Servicing

The detector shall be designed for ease of maintenance; that is, to clean,
inspect, adjust, align, and repair. The electronics shall be of modular design
and easily accessible for maintenance and repair.

2.7 Detector Mount

The manufacturer shall provide with each detector, if requested, a detector
mount for positioning the walk-through metal detector for performance
tests. See figure 2. The detector mount (see fig. 5) shall comply with the
requirements of section 2.1.2 and shall meet the following specifications:

a. Relative permeability = 1.0 [plus or minus] 0.001.

b. Electrical conductivity < 10[-8] Siemens/m.

c. Mass [less than or equal to]50 kg (110 lb).

d. Flatness of surface mating to reference surface [plus or minus] 0.5 mm
(0.041 in).

e. Hold the detector in position.

f. Mate with the reference surface (see fig. 6).

g. Fastener holes that align with each of the (two to four) 3/8-16 fastener
holes of the reference surface (see fig. 6).

h. Hold the detector so that the detector plane and the x-z plane of the
measurement coordinate system are parallel to within [plus or minus] 1
degree.

i. Hold the detector so that the detector plane is 0.5 m [plus or minus] 0.01
m from the reference surface (see figs. 2 and 6).

j. Position the detector floor at a height of 32.5 cm [plus or minus] 0.5 cm
above the ground surface (see fig. 5).

k. Provide a 1 cm [plus or minus] 0.1 cm groove for the steel reinforced
floor test panel at a height of 22.5 cm [plus or minus] 0.5 cm above the
ground surface (see fig. 5).

2.8 Quality Control and Assurance

2.8.1 Quality System

The manufacturer shall meet the requirements of ISO 9001:2000, as
amended.

2.8.2 Testing and Calibration Laboratories

Laboratories performing testing and calibration of the detector and/or its
components shall meet the requirements of IEC 17025.

2.8.3 Measurement Equipment and Processes

All measurement equipment and processes shall meet the requirements of
ISO 10012-1 and ISO 10012-2.

2.8.4 Burn-In

Power-on dynamic burn-in testing for a set of metal detectors of the same
model is required in accordance with section 3.5. The set shall consist of m
detectors of the same type and model selected using simple random
sampling methods and tested without replacement (where m=ceil
(0.1Mk[m]/0.1k[m]+0.01M), M is the number of the manufactured
detectors of the same model, ceil is a function that returns the smallest
integer greater than or equal to its argument, and k[M] is the coverage
factor for the 99 % confidence interval, see Table B.1 of B.N. Taylor and
C.E. Kuyatt, NIST Technical Note 1297, Guidelines for Evaluating and
Expressing the Uncertainty of NIST Measurement Results, U.S.
Government Printing Office, Washington, DC, 1994). The manufacturer
shall provide the test results of this randomly selected set of same type and
model detectors.

2.9 Documentation

The manufacturer shall provide the following list of deliverable items with
each detector unless otherwise indicated.

2.9.1 Operating Instructions

The manufacturer or distributor shall supply with each detector an
operator's manual that shall contain at least the following information:

a. The purpose of the detector.

b. A description of operator controls.

c. A listing of the operating features.

d. A description of the detection principles and detector capabilities.

e. A block diagram showing the major internal functional components.

f. An exposure warning that states "This Device May Affect Personal
Medical Electronic Devices." This warning shall be in place until such time
that the Food and Drug Administration or some other competent Federal
agency requires a different warning or has determined that no such warning
is necessary.

2.9.2 Operator Training Instructions and Videotape or CD-ROM

A training package shall be supplied upon request that will provide
operators with the information necessary to acquire the technical and
operational skills required to conduct effective screening with the detector.
The training package shall include an audio/visual videotape or CD-ROM
as well as an operator's manual. For additional guidance in formulating the
operator training package, review A Users' Guide for Hand-Held and
Walk-Through Metal Weapon Detectors, published by the National
Institute of Justice. The manufacturer shall have demonstrated the
effectiveness of the training material when 50 % of the test group receiving
the training understands the operation of the detector, passes a written test,
and operates the detector successfully. The test group shall consist of at
least 10 people with only a high school education.

2.9.3 Technical Manual

A technical manual shall be provided upon request which contains all of the
information that could be required by a technician to troubleshoot,
maintain, and repair the equipment to the component level.

2.9.4 Technical Training Manual and Videotape or CD-ROM

A self-study training package shall be provided upon request for use by site
maintenance technicians. The training package must consist of an
audio/visual videotape or CD-ROM as well as a technical manual that
provides detailed explanations of circuit theory and maintenance
procedures.

2.9.5 Technical Specifications

The manufacturer shall provide, upon request, a detailed listing of all
relevant specifications of the detector. This listing shall include at a
minimum:

a. Detector object size class (as defined in sec. 1.2.14).

b. Mechanical drawings of the detector with dimensions in metric units.

c. Mass of the detector.

d. Allowable range of ac line power supply voltage.

e. Battery type, quantity, and life.

f. Maximum magnetic field strength that can be found on the detector
surface.

g. If applicable, operating frequency and, if applicable, modulation
parameters.

h. If applicable, pulse repetition rate, pulse duration, and pulse transition
duration.

i. Operating ambient temperature range.

2.9.6 Certifications of Test, Inspection, and Conformance

The manufacturer shall provide upon request a certification of all
mandatory tests, test procedures, testing laboratories, compliance to
required standards, a record of the test results for the detector, and the
identities of all the companies, laboratories, and/or organizations
conducting the tests.

2.9.7 Suggested Maintenance Schedule

The manufacturer shall provide a preventive maintenance schedule and a
detailed list of the technical skills, computer hardware, and software tools
required.

2.9.8 Installation Instructions

The manufacturer shall provide detailed instructions for the location and
installation of the walk-through metal detector. The manufacturer shall also
provide instructions for battery installation and specify the type and
quantity of batteries required.

3. PERFORMANCE TESTING PROCEDURES

The detector shall meet the detection performance requirements for each
object size class in which it is required to operate. The detection
performance shall be evaluated by the test methods described in this
section. The manufacturer shall record and provide the test results on the
report forms mentioned in section 6 of this randomly selected set of same
type and model detectors.

3.1 General Test Conditions

3.1.1 Test Location

The distance between any metal object other than a test object shall be at
least 15 cm from the detector floor, at least 15 cm from the topmost part of
the detector, and at least 0.8 cm from any side or outward projections of
any side of the detector.

3.1.2 Environment

At the time of the tests, the ambient temperature shall be in the range
specified in section 2.4.3.1 for the appropriate application (indoor,
sheltered outdoor, or outdoor); the relative humidity shall be
noncondensing.

3.1.3 Preparations

The walk-through metal detector shall be installed according to the
manufacturer's instructions. Any setup or calibration adjustments specified
in the operator's manual shall be performed if required.

3.2 Detection Performance Tests

For walk-through metal detectors that contain more than one generator
and/or sensor, the detector response shall be recorded for each generator
or sensor appropriate for the location of the test object within the portal
region of the detector.

3.2.1 Object Size Classes

If the detector can be adjusted to provide an alarm indication for both large
object size and medium object size, the detection performance test shall be
performed for each object size class. The detection performance shall be
evaluated by the test methods described in this section.

3.2.2 Equipment

3.2.2.1 Test Objects

Test objects shall be as described in section 5. There are up to three
orientation holes on up to three surfaces of the test object (encased replica
of a threat item). The tapped hole on each surface of the test objects is
labeled with an "A" (see mechanical drawings in sec. 5 showing the
encased test object) and is the center of rotation of the different
orientations. The test objects shall be oriented such that their orienting
holes that are being used are facing the three-axis positioning system and
the hole labeled "A" is below the other orientation hole being used.
Labeling for the test object orientation shall use two characters: the first
character indicates in which quadrant of the mechanical drawing the
specified orientation can be found, and the second character indicates the
position of the unused hole relative to the hole labeled "A." The quadrant
designations are given as follows:

-- "1" indicates bottom left.

-- "2" indicate bottom right.

-- "3" indicates top left.

-- "4" indicates top right.

Not all quadrants are used. For the second character, "L" indicates that the
unused hole is to the left of the hole labeled "A," and "R" indicates that the
unused hole is to the right of the hole labeled "A."

3.2.2.2 Three-Axes Positioning System

The three-axes positioning system shall meet the following requirements:

a. Displacement, x and y axes: [greater than or equal to] 1 m.

b. Displacement, z axis: [greater than or equal to] 2 m.

c. Position accuracy, each axis: 1 mm.

d. Position repeatability, each axis: 1 mm.

e. Maximum slew speed, y axis: [greater than or equal to] 2 m/s.

3.2.2.3 Magnetic Field Sensor

The magnetic field sensor shall have a frequency response bandwidth at
least five times greater than the bandwidth of the generated magnetic field,
provide a rms voltage output, and have dimensions less than or equal to 4
cm x 4 cm x 4 cm.

3.2.2.4 Voltmeter

The ac voltmeter shall have a bandwidth at least five times greater than the
bandwidth of the generated magnetic field, allow computer control and
data retrieval, and have a variable gain input with at least 10-bit resolution
full scale.

3.2.2.5 Microphone (Audible Alarm Indicators)

The microphone is the audible alarm indication detector. It shall be used to
detect an audible positive alarm indication, be capable of detecting the
audible alarm indication as described in section 2.6.2, and provide an
analog output that can be interfaced to the computer controller (see sec.
3.2.2.8).

3.2.2.6 Light Detector (Visible Alarm Indicators)

The light detector is the visible alarm indication detector. It shall be used to
detect a visible positive alarm indication, be capable of being attached
directly to the visual alarm indicator, and provide an analog electrical
output that can be interfaced to the computer controller (see sec. 3.2.2.8).

3.2.2.7 Detector Positioner

The detector positioner is a nonconductive, nonmagnetic device that
provides a reference surface on which to securely attach the detector
mount and that maintains the detector plane at a fixed location in the
measurement coordinate system relative to the three-axes positioning
system. A detailed mechanical drawing of the reference surface is provided
in figure 6.

3.2.2.8 Computer Controller

The computer controller shall have installed and operational all necessary
hardware and software for providing instrument control and data
acquisition.

3.2.3 Detection Sensitivity

3.2.3.1 Initial Procedures

Ensure that the voltmeter, alarm indication detector, and three-axes
positioning system are connected to the computer controller and that the
detection signal output connector (see sec. 2.6.3) is connected to the
voltmeter (for analog signals) or to the computer (for digital signals). Turn
on the voltmeter, alarm indication detector, computer controller, and
positioning system and verify proper operation of the measurement system.
Ensure that the walk-through metal detector is securely located and
positioned in the measurement coordinate system. Attach the test object
with the proper orientation to the positioning system. Turn on the walk-
through metal detector and ensure that its output functions properly by
noting a change in the magnitude of the detection signal and activation of
the alarm indication as a metal object is brought near the detector. Ensure
that the test object does not hit any objects while in motion.

3.2.3.2 Performing the Measurement

The scan limits for the x-axis scan shall be the boundaries of the test
measurement grid locations. The center for both the x and z direction scans
shall be the detector axis (see fig. 1). Set the computer program to perform
a one-meter-long y-axis scan at the specified speed that is perpendicular to,
passes through, and is centered at the detector plane. Set the x-axis and z-
axis positions to the most negative scan limits. Perform a y-axis scan,
measure the signal present at the detection signal output connector (see
sec. 2.6.3), and record this measurement as the y-axis is scanned in the
forward direction. (Alternatively, perform a y-axis scan and record any
positive alarm indication in the forward direction using the alarm indication
detector.) Move the x axis in 5 cm [plus or minus] 0.1 cm increments and
repeat the y-axis scan measurement for each x-axis increment until the
x-axis positive scan limit is reached. Move the z axis in 5 cm [plus or
minus] 0.1 cm increments while repeating the x-axis incremented motion
and the y-axis scan measurement until the z-axis positive scan limit is
reached. (Alternatively, adjust the detector sensitivity settings either after
each scan has been performed or after scans at all of the test measurement
grid locations have been performed and determine the threshold for test
object detection at each test measurement grid location.) Record the
average detection signal value for each y-axis scan and report these values.
Record any positive alarm indication using the alarm indication detector as
the y-axis scan is being performed. (Alternatively, record the detector
threshold sensitivity settings for each y-axis scan and report these values.)

3.2.4 Speed

3.2.4.1 Initial Procedures

Ensure that the alarm indication detector and three-axes positioning system
are connected to the computer controller. Turn on the alarm indication
detector, the computer controller, and the three-axes positioning system
and verify proper operation of the measurement system. Ensure that the
walk-through metal detector is securely located and positioned within the
measurement coordinate system. Adjust the detector to the appropriate
sensitivity setting. Attach the test object with the proper orientation to the
three-axes positioning system. Turn on the walk-through metal detector
and ensure that its output functions properly by noting a change in the
alarm indication detector reading as a metal object is brought near the
portal region. Ensure that the test object does not hit any objects while in
motion.

3.2.4.2 Performing the Measurement

Set the computer program to perform a one-meter-long y-axis scan at the
specified speed that is perpendicular to, passes through, and is centered at
the detector plane at the specified x-axis and z-axis position. Record any
positive alarm indication using the alarm indication detector as the y-axis
scan is being performed.

3.2.5 Discrimination

3.2.5.1 Initial Procedures

See section 3.2.4.1.

3.2.5.2 Performing the Measurement

Set the computer program to perform a one-meter-long y-axis scan that is
perpendicular to, passes through, and is centered at the detector plane at
the x-axis position of 0 cm [plus or minus] 0.5 cm centered on the z-axis
and z-axis position of 60 cm [plus or minus] 0.5 cm. Attach the three-axis
positioning system to the innocuous item test object holder (see sec. 5.4.3)
at the designated location on the innocuous item test object holder.
Perform the y-axis scan and record any positive alarm indication using the
alarm indication detector as the y-axis scan is being performed.

3.2.6 Body Interference

The detector shall be placed in a sufficiently stable location so that walking
through the portal does not cause a positive alarm indication.

3.2.6.1 Initial Procedures

Select a clean tester. Ensure that the alarm indication detector is connected
to the computer. Turn on the alarm indication detector and computer
controller and verify proper operation of the measurement system. Ensure
that the detector sensitivity settings are appropriate for the desired object
size class.

3.2.6.2 Performing the Measurement

Direct the clean tester to walk through the center of the portal of the metal
detector at a speed of approximately 1.0 m/s. Record any positive alarm
indication using the alarm indication detector as the clean tester passes
through the portal.

3.2.7 Throughput Rate

3.2.7.1 Initial Procedures

See section 3.2.4.1. Position the test object support platform (see sec.
3.2.7.3) so that the detector axis is parallel to and the detector plane
perpendicular to the top surface of the support platform and the z-axis of
the detector is centered [plus or minus] 1 cm in both the width and the
length of the support platform. A forward-going scan direction moves the
test object farther away from the three-axis positioning system and through
the detector portal. A backward-going scan direction moves the test object
through the detector portal and closer to the three-axis positioning system.
The delay is the difference between the stopping time of the forward-going
scan and the starting time of the negative-going scan. This procedure
requires two test objects. The first test object is attached to the positioning
system and is the one referenced in section 2.3.5. The second test object, a
large size test object, is not attached to the positioning system and is
pushed by the first test object through the detector portal during the
forward-going scan.

3.2.7.2 Performing the Measurement

Set the computer program to perform a one-meter-long y-axis scan at the
specified measurement conditions and set the y-axis scan position to -0.5 m
[plus or minus] 1 cm from the detector plane. Rest the top panel of the test
object support platform (see sec. 3.2.7.3) on the dowel pins closest to the
specified z-axis position. Attach the first test object to the positioning
system. Place the second test object on top of the test object support
platform, against the first test object, and orient the second test object as
shown in the bottom right of the mechanical drawing of the encased replica
(see sec. 5.1). Perform the forward-going y-axis scan, record any positive
alarm indication using the alarm indication detector as the forward-going y-
axis scan is being performed, record the time at which the forward-going y-
axis scan terminated, wait for a delay of 2.0 s [plus or minus] 0.05 s,
perform the backward-going y-axis scan, and record any positive alarm
indication using the alarm indication detector as the backward-going y-axis
scan is being performed. Decrease the delay by 0.1 s [plus or minus] 0.01 s,
repeat the procedure described in the previous sentence until no alarm
indication is observed for the backward-going y-axis scan, and record this
delay for the specified z-axis position. Repeat this process for all specified
z-axis positions. Take the longest of this set of recorded delays, add 0.1 s
to get the corrected delay, and divide 60 s/min by the corrected delay to
get the throughput rate.

3.2.7.3 Test-Object Support Platform

This section contains a description of a test object support platform. The
purpose of the support platform is to provide a rest for the test objects at
the test measurement location (see fig. 4) heights of 78 cm, 130 cm, and
178 cm. The test-object support platform shall be constructed using the
following items and as shown in figures 7 and 8.

A. Cross pieces, 6 each, wood "1x4," 65 cm [plus or minus] 1 cm long,
with the following hole pattern:

--Two holes each end 
o 9.5 mm [plus or minus] 0.5 mm dia, through hole
o 4 cm [plus or minus] 0.1 cm from the end
o First hole 3 cm [plus or minus] 0.1 cm from the top edge
o Second hole 6 cm [plus or minus] 0.1 cm from the top edge

B. Sides, 2 each, plywood "1/2-inch," 101 cm [plus or minus] 1 cm x 1.2 m
[plus or minus] 1 cm, with the following hole pattern:

--Three holes each along each short (101 cm) edge
o 9.5 mm [plus or minus] 0.5 mm dia, through hole
o 2 cm [plus or minus] 0.1 cm from the edge
o First hole 4.5 cm [plus or minus] 0.1 cm from the bottom edge
o Second hole 62.5 cm [plus or minus] 0.1 cm from the bottom edge
o Third hole 96.5 cm [plus or minus] 0.1 cm from the bottom edge

C. Posts, 4 each, wood "2x4," 1.8 m [plus or minus] 1 cm long, with the
following hole pattern:

--Three holes each centered on the narrow side of the "2x4," for side (item
B) attachment
o 9.5 mm [plus or minus] 0.5 mm dia, 2 cm [plus or minus] 0.5 cm deep
o First hole 77.5 cm [plus or minus] 0.1 cm from the bottom end
o Second hole 135.5 cm [plus or minus] 0.1 cm from the bottom end
o Third hole 169.5 cm [plus or minus] 0.1 cm from the bottom end

--Six holes each centered on the broad side of the "2x4," for cross piece
(item A) attachment
o 9.5 mm [plus or minus] 0.5 mm dia, through holes
o First hole 76 cm [plus or minus] 0.1 cm from the bottom end
o Second hole 79 cm [plus or minus] 0.1 cm from the bottom end
o Third hole 134 cm [plus or minus] 0.1 cm from the bottom end
o Fourth hole 137 cm [plus or minus] 0.1 cm from the bottom end
o Fifth hole 168 cm [plus or minus] 0.1 cm from the bottom end
o Sixth hole 171 cm [plus or minus] 0.1 cm from the bottom end

D. Platform, 1 each, plywood "1/2-inch," 165 cm [plus or minus] 1 cm x 44
cm [plus or minus] 1 cm, with the following hole pattern:

--Three holes each on one narrow (44 cm) end:
o 9.5 mm [plus or minus] 0.5 mm dia, through holes
o 2 cm [plus or minus] 0.1 cm from the edge
o First hole 11 cm [plus or minus] 0.1 cm from the bottom edge
o Second hole 22 cm [plus or minus] 0.1 cm from the bottom edge
o Third hole 33 cm [plus or minus] 0.1 cm from the bottom edge

E. Backstop, 1 each, wood "2x4," 44 cm [plus or minus] 1 cm long, with
the following hole pattern:

--Three holes each on one narrow side of the "2x4":
o 9.5 mm [plus or minus] 0.5 mm dia, 2 cm [plus or minus] 0.5 cm deep
o 2 cm [plus or minus] 0.1 cm from the edge
o First hole 11 cm [plus or minus] 0.1 cm from the bottom edge
o Second hole 22 cm [plus or minus] 0.1 cm from the bottom edge
o Third hole 33 cm [plus or minus] 0.1 cm from the bottom edge

F. Dowels, 39 each, hardwood, 9.5 mm [plus or minus] 0.5 mm dia, 3 cm
[plus or minus] 0.5 cm long

Assemble item E to D using dowels (item F). Assemble item B to C and
then A to C using dowels (item F).

3.2.8 Multiple Object Interference

3.2.8.1 Initial Procedures

See section 3.2.4.1. Attach the steel handgun replica (see mechanical
drawing of the encased test object in sec. 5.1) to three-axis positioning
system in the orientation shown in the bottom right of the drawing such
that the plane through the point labeled "A" that is parallel to the bottom
surface of the encasement is parallel to the detector floor. Attach the
aluminum handgun replica, using the same orientation as that of the steel
handgun replica, to the steel handgun replica using nonelectrically
conductive nonmagnetic tape.

3.2.8.2 Performing the Measurement

Set the computer program to perform a one-meter-long y-axis scan at 1.0
m/s [plus or minus] 0.1 m/s that is perpendicular to, passes through, and is
centered at the detector plane at the x-axis position of 0 cm [plus or minus]
1 cm centered on the z-axis at the z-axis position of 80 cm [plus or minus]
1 cm. Perform the y-axis scan and record any positive alarm indication
using the alarm indication detector as the y-axis scan is being performed.
Repeat the y-axis scan for the z-axis position of 110 cm [plus or minus] 1
cm and 130 cm [plus or minus] 1 cm, and record any positive alarm
indication using the alarm indication detector as the y-axis scan is being
performed.

3.3 Alarm Indication Test

3.3.1 Equipment

3.3.1.1 Sound Level Meter

The sound pressure level meter shall comply with ANSI S1.4, 1971, for
type 3, A-weighting, reference pressure 20 [micro]Pa.

3.3.1.2 Illumination Meter

The illumination meter shall be capable of measuring light levels of 25
lm/m[2] and 10,000 lm/m[2] with an error of not more than 10 %. The
integrated spectral response shall be within 10 % of the Commission
Internationale de l'Eclairage (CIE, the International Commission on
Illumination) photopic curve.

3.3.2 Sound Pressure Level Test

Perform the test in an anechoic chamber or at an outdoor location, at least
6 m (20 ft) from any large object, where the ambient sound pressure level
at the time of the test is not more than 53 dB[SPL]. Position the sound
pressure level meter microphone 0.80 m (31 in) from the detector. Measure
the sound pressure level with the detector power applied and the alarm
indicator in the nonalarm state. Then position the appropriate test object at
a test separation distance of 5 cm (2 in) to produce an alarm, and again
measure the sound pressure level.

3.3.3 Visible Alarm Indicator Test

Position the detector with its alarm indicator 0.80 m [plus or minus] 0.05 m
from the eyes, at a test site where the ambient illumination is 10 000
lm/m[2] [plus or minus] 1000 lm/m[2]. After waiting at least 3 min to allow
for eye accommodation, turn on the detector and move a metal object near
the detector to cause an alarm. Observe the indication. Repeat the test at a
test site where the ambient illumination is 25 lux [plus or minus] 2.5 lux.

3.4 Test for Operation Near a Metal Wall, Steel Reinforced Floor, or
Moving Metal Door

3.4.1 Stationary Metal Objects, Wall

The effects of the proximity of a metal wall or floor on the performance of
the walk-through metal detector is assessed using a metal test panel.

3.4.1.1 Metal Test Panel

The metal test panel shall be cold-finished sheet carbon steel AISI C1015
to C1020 with dimensions of 1 m [plus or minus] 0.1 m by 1 m [plus or
minus] 0.1 m by 0.75 mm [plus or minus] 0.13 mm and mounted in a
nonelectrically conductive, nonmagnetizable frame to prevent bowing and
bending of the metal test panel.

3.4.1.2 Test Procedure

Position the metal test panel such that its large surfaces are perpendicular
to the detector plane, the x axis of the measurement coordinate system
passes through the center of the metal test panel, and the x-axis separation
between the metal test panel and the detector axis is 0.5 m [plus or minus]
0.01 m. Note and record any positive alarm indication after the panel is
positioned and test the metal detector according to section 2.3.3 without
moving the metal test panel. Perform this test on both sides of the
walk-through metal detector portal.

3.4.2 Steel Reinforced Floor

The effects of the proximity of a steel reinforced floor on the performance
of the walk-through metal detector is assessed using a metal test panel.

3.4.2.1 Metal Test Panel, Steel Reinforced Floor

The test floor shall be cold-finished sheet carbon steel AISI C1015 to
C1020 with dimensions of 1 m [plus or minus] 0.01 m by 1 m [plus or
minus] 0.01 m by 2 mm [plus or minus] 0.2 mm.

3.4.2.2 Test Procedure

Position the metal test panel such that it fits firmly in the grooves of the
detector mount and is parallel with the ground surface (see fig. 5). Note
and record any positive alarm indication after the panel is positioned and
test the metal detector according to section 2.3.3 without moving the metal
test panel.

3.4.3 Moving Metal Door

The effects of the proximity of a moving metal door on the performance of
the walk-through metal detector is simulated using a pivoting metal test
panel.

3.4.3.1 Metal Test Door

The metal test door shall consist of a metal plate made of cold-finished
sheet carbon steel AISI C1015 to C1020 with dimensions of 2 m [plus or
minus] 0.02 m by 1 m [plus or minus] 0.02 m by 2 mm [plus or minus] 0.2
mm attached with hinges to a stationary wooden frame such that the metal
plate can swing 180 [degrees] without obstruction.

3.4.3.2 Test Procedure

Position the metal test door such that the plane defined by the position of
the metal plate at 0 [degrees] and 180 [degrees] is parallel to the detector
plane, the detector axis is in the plane of the metal plate when the metal
plate is in the 90 [degrees] position, and the edge of the metal plate closest
to the detector is 2 m [plus or minus] 0.1 m from detector plane when the
metal plate is at the 90 [degrees] position. Place the metal plate at the 0
[degrees] position. Rotate the metal plate to the 180 [degrees] position in 4
s [plus or minus] 1 s and record any positive alarm indications.

3.5 Burn-In Test

The burn-in test is to be performed for a minimum of 160 consecutive
hours, with the last 40 h failure free.

3.5.1 Cycling of the Equipment

Once each working shift (8 h), the detector shall be cycled on and off 10
times within 20 s and immediately (within 60 s) tested in accordance with
section 2.3.3.

3.5.2 Performance Evaluation

Once each working shift (8 h), the detector shall be tested according to
section 2.3.3 and section 2.3.4.

4. FIELD TESTING PROCEDURES

4.1 Large Object Size

The detector shall be turned on, and a clean tester shall walk through the
detector portal carrying each of the large object size test objects described
in section 5.1, one at a time, to assure that the objects are properly
detected. The clean tester shall then walk through the detector portal
carrying each of the appropriate innocuous item test objects described in
section 5.4.1 to assure that the objects are not detected. Repeat this test
three times at pass-through speeds ranging from approximately 0.5 m/s to
approximately 1.5 m/s to assure proper detector performance.

4.2 Medium Object Size

The detector shall be turned on and a clean tester shall walk through the
detector portal carrying each of the medium object size test objects
described in section 5.2, one at a time, to assure that the objects are
properly detected. The clean tester shall then walk through the detector
portal carrying each of the appropriate innocuous item test objects
described in section 5.4.2 to assure that the objects are not detected. 
Repeat this test three times at pass-through speeds ranging from
approximately 0.5 m/s to approximately 1.5 m/s to assure proper detector
performance.

4.3 Small Object Size

The detector shall be turned on and a clean tester shall walk through the
detector portal carrying each of the small object size test objects described
in section 5.3, one at a time, to assure that the objects are properly
detected. Repeat this test three times at pass-through speeds ranging from
approximately 0.5 m/s to approximately 1.5 m/s to assure proper detector
performance.

5. TEST OBJECTS DESCRIPTION

This section contains mechanical drawings of the test objects. The test
objects are encased replicas of threat items. The dimensions in all the
mechanical drawings of this section are in units of millimeters (mm).

5.1 Large Object Size Test Objects

The following mechanical drawings are of the replica of the large object
size item that is considered a threat to an officer, a prisoner, an inmate, and
the public safety. The large object size threat item is a handgun. The
mechanical drawings are arranged in the following order: the mechanical
drawing of the replica of the handgun and the location of the replica within
the encasement. Three replicas are made and encased, one from each of the
materials indicated in the drawings.

5.2 Medium Object Size Test Objects

The following mechanical drawings are of the replica of the medium object
size item that is considered a threat to an officer, a prisoner, an inmate, and
the public safety. The medium object size threat item is a knife. The
mechanical drawings are arranged in the following order: the mechanical
drawing of the replica of the knife and the location of the replica within the
encasement. Two replicas are made and encased, one from each of the
materials indicated in the drawings.

5.3 Small Object Size Test Objects

The following mechanical drawings are replicas of the small hard-to-find
items considered a threat to officer and prisoner safety and that can be used
to defeat security measures. These items are replicas of: a handcuff key, a
nonferromagnetic stainless steel knife, and a #2 Phillips screwdriver bit.

5.3.1 Handcuff Key

This section contains the following mechanical drawings: a replica of a
handcuff key, a small object size test object; and the location of the test
object within the encasement. Two replicas are made and encased, one
from each of the materials indicated in the drawing.

5.3.2 Nonferromagnetic Stainless Steel Knife

This section contains the following mechanical drawings: a replica of a
nonferromagnetic stainless steel knife, a small object size test object; and
the location of the test object within the encasement.

5.3.3 Screwdriver Bit, Phillips, #2

This section contains the following mechanical drawings: a replica of a #2
Phillips screwdriver bit, a small object size test object; and the location of
the test object within the encasement.

5.4 Innocuous Item Test Objects

5.4.1 Large Object Size

The innocuous item test objects for the large object size detector
classification are the set of coins and the replicas of a set of coins, a belt
buckle, eyeglasses, a key ring with keys, a cigarette pack, and a watch.

5.4.1.1 Set of Coins

The set of coins shall consist of two each United States (U.S.) pennies,
U.S. nickels, U.S. dimes, and U.S. quarters minted between the years 1990
and 2000.

5.4.1.2 Belt Buckle

The replica of the belt buckle, an innocuous item test object, shall be made
from a rod of stainless steel, classification UNS S30400, having a diameter
of 6.4 mm [plus or minus] 0.4 mm, and bending into a circle with an inside
diameter of 50 mm [plus or minus] 5 mm.

5.4.1.3 Eyeglasses

The following provides the mechanical drawings for the replica of the
eyeglasses, an innocuous item test object.

5.4.1.4 Watch

The replica of the watch, an innocuous item test object, shall be made from
a disc-shaped object. The following provides the physical dimensions and
material designation for the replica of the watch:

--diameter: 30 mm [plus or minus] 5 mm

--thickness: 5 mm [plus or minus] 1 mm

--material: UNS S30400.

5.4.2 Medium Object Size

The innocuous item test objects for the medium object size detector
classification are the replicas of the eyeglasses and the belt buckle.

5.4.3 Innocuous Item Test Object Holder

The first drawing shows the location of the innocuous item test objects on
the innocuous item test object holder, and the subsequent mechanical
drawings are of the parts of the innocuous item test object holder and its
assembly. All components of the holder shall be constructed of
nonelectrically conductive and nonmagnetic materials.

6. COMPLIANCE TEST REPORT FORM

The Compliance Test Report (CTR) form shall be used in conjunction with
NIJ Standard-0601.02, Walk-Through Metal Detectors for Use in
Concealed Weapon and Contraband Detection, and shall become a part of
the official records of the compliance testing of each metal detector model
submitted for testing. All sections of the form shall be completed.

An electronic file of the report form is available from the NLECTC
Compliance Testing Office, National Law Enforcement and Corrections
Technology Center-National (NLECTC-National). Requests for this file
can be sent to: NLECTC-National, Attn: Metal Detector Testing Program,
P.O. Box 1160, Rockville, MD 20849-1160; or to the E-mail address,
asknlectc@nlectc.org.

7. REFERENCES

The following normative documents contain provisions, which through
reference in this text, constitute provisions of this Standards Publication.
By reference herein these publications are adopted, in whole or in part, as
indicated.

ACGIH-0302 (1996), American Conference of Governmental Industrial
Hygienists, Documentation of the Threshold Limit Values, Sub-Radio
Frequency (30 kHz and below) Magnetic Fields.

ANSI S1.4, 1971, American National Standards Institute, Specifications
for General Purpose Sound Level Meters.

ASTM Designation F 1468-95, Section 13, American Society for Testing
and Materials, Standard Practice for Evaluation of Metallic Weapons
Detectors for Controlled Access Search and Screening, Section 13,
Procedure for Testing for Outside Influences: Electrical.

EN 50081-1 1992, European Standard, Electromagnetic Compatibility -
Generic Emission Standard, Part 1: Residential, Commercial, and Light
Industry.

EN 50082-1 1998, European Standard, Electromagnetic Compatibility -
Generic Immunity Standard, Part 1: Residential, Commercial, and Light
Industry.

IEC 68-2-27 1987, International Electrotechnical Commission, Basic
Environmental Testing Procedures, Part 2: Tests - Test Ea and Guidance:
Shock.

IEC 68-2-29 1987, International Electrotechnical Commission, Basic
Environmental Testing Procedures, Part 2: Tests - Test Eb and Guidance:
Bump.

IEC 60529 2001-2, International Electrotechnical Commission, Degrees of
Protection Provided by Enclosures (IP Code).

IEEE C95.1-1991, Institute of Electrical and Electronic Engineers,
Standard for Safety Levels with Respect to Human Exposure to Radio
Frequency Electromagnetic Fields, 3 kHz to 300 GHz.

ISO 9001:2000, International Organization for Standardization 9001,
Quality Systems - Model for Quality Assurance in Design, Development,
Production, Installation and Servicing.

ISO 10012-1:1993-01-15, International Standards Organization, Quality
Assurance Requirements for Measuring Equipment, Part 1: Metrological
Confirmation System for Measuring Equipment.

ISO 10012-2:1997-09-15, International Standards Organization, Quality
Assurance for Measuring Equipment, Part 2: Guidelines for control
measurement process.

ISO 17025:1999-12-15, International Standards Organization, General
Requirements for the Competence of Testing and Calibration Laboratories.

MIL-STD-461E Method RS101, Military Standard, Requirements for the
Control of Electromagnetic Interference Characteristics of Subsystems and
Equipment, Method RS101, Radiated Susceptibility, Magnetic Field, 30 Hz
to 100 kHz.

MIL-STD-810F Method 501.4, Military Standard, Test Method Standard
for Environmental Engineering Considerations and Laboratory Tests,
Method 501.4, High Temperature.

MIL-STD-810F Method 502.4, Military Standard, Test Method Standard
for Environmental Engineering Considerations and Laboratory Tests,
Method 502.4, Low Temperature.

MIL-STD-810F Method 505.4, Military Standard, Test Method Standard
for Environmental Engineering Considerations and Laboratory Tests,
Method 505.4, Solar Radiation (Sunshine).

MIL-STD-810F Method 507.4, Military Standard, Test Method Standard
for Environmental Engineering Considerations and Laboratory Tests,
Method 507.4, Humidity.

MIL-STD-810F Method 509.4, Military Standard, Test Method Standard
for Environmental Engineering Considerations and Laboratory Tests,
Method 509.4, Salt Fog.

NIJ, National Institute of Justice, A Users' Guide for Hand-Held and Walk-
Through Metal Weapon Detectors, 2000.

NIST Technical Note 1297, Guidelines for evaluating and expressing the
uncertainty of NIST measurement results, U.S. Dept. of Commerce, 1994.

Safety Code, Recommended Safety Procedures for the Selection,
Installation and Use of Active Metal Detectors, Radiation Protection
Bureau, Canadian Minister of National Health and Welfare.

UL 60950, Underwriters Laboratories, Safety for Information Technology
Equipment.

------------------------------

About the Law Enforcement and Corrections Standards and Testing
Program

The Law Enforcement and Corrections Standards and Testing Program is
sponsored by the Office of Science and Technology of the National
Institute of Justice (NIJ), U.S. Department of Justice. The program
responds to the mandate of the Justice System Improvement Act of 1979,
which directed NIJ to encourage research and development to improve the
criminal justice system and to disseminate the results to Federal, State, and
local agencies.

The Law Enforcement and Corrections Standards and Testing Program is
an applied research effort that determines the technological needs of justice
system agencies, sets minimum performance standards for specific devices,
tests commercially available equipment against those standards, and
disseminates the standards and the test results to criminal justice agencies
nationally and internationally.

The program operates through:

The Law Enforcement and Corrections Technology Advisory Council
(LECTAC), consisting of nationally recognized criminal justice
practitioners from Federal, State, and local agencies, which assesses
technological needs and sets priorities for research programs and items to
be evaluated and tested.

The Office of Law Enforcement Standards (OLES) at the National Institute
of Standards and Technology, which develops voluntary national
performance standards for compliance testing to ensure that individual
items of equipment are suitable for use by criminal justice agencies. The
standards are based upon laboratory testing and evaluation of
representative samples of each item of equipment to determine the key
attributes, develop test methods, and establish minimum performance
requirements for each essential attribute. In addition to the highly technical
standards, OLES also produces technical reports and user guidelines that
explain in nontechnical terms the capabilities of available equipment.

The National Law Enforcement and Corrections Technology Center
(NLECTC), operated by a grantee, which supervises a national compliance
testing program conducted by independent laboratories. The standards
developed by OLES serve as performance benchmarks against which
commercial equipment is measured. The facilities, personnel, and testing
capabilities of the independent laboratories are evaluated by OLES prior to
testing each item of equipment, and OLES helps the NLECTC staff review
and analyze data. Test results are published in Equipment Performance
Reports designed to help justice system procurement officials make
informed purchasing decisions.

Publications are available at no charge through the National Law
Enforcement and Corrections Technology Center. Some documents are
also available online through the Internet/World Wide Web. To request a
document or additional information, call 800-248-2742 or 301-519-5060,
or write:

National Law Enforcement and Corrections Technology Center P.O. Box
1160 Rockville, MD 20849-1160 E-Mail: asknlectc@nlectc.org World
Wide Web address: http://www.nlectc.org

 ------------------------------

This document is not intended to create, does not create, and may not be
relied upon to create any rights, substantive or procedural, enforceable at
law by any party in any matter civil or criminal.

Opinions or points of view expressed in this document represent a
consensus of the authors and do not represent the official position or
policies of the U.S. Department of Justice. The products and manufacturers
discussed in this document are presented for informational purposes only
and do not constitute product approval or endorsement by the U.S.
Department of Justice.

The National Institute of Justice is a component of the Office of Justice
Programs, which also includes the Bureau of Justice Assistance, the Bureau
of Justice Statistics, the Office of Juvenile Justice and Delinquency
Prevention, and the Office for Victims of Crime.

------------------------------

NCJ 193510