NBSIR 73-223

Penetration Tests on J-SIIDS Barriers

R. T. Moore

Measurements Automation Section

Information Processing Technology Division

Institute for Computer Sciences and

Technology

Washington, D. C. 20234

June 4, 1973

Interim Report for Period March 13 - 16, 1973

Prepared for Defense Nuclear Agency

Washington, D. C. 20305

NBSIR 73-223

PENETRATION TESTS ON J-SIIDS BARRIERS

R. T. Moore

Measurements Automation Section

Information Processing Technology Division

Institute for Computer Sciences and

Technology

Washington, D. C. 20234

June 4, 1973

Interim Report for Period March 13 - 16, 1973

Prepared for Defense Nuclear Agency

Washington, D. C. 20305

U. S. DEPARTMENT OF COMMERCE, Frederick B. Dent, Secretary

IMATIONAL BUREAU OF STANDARDS, Richard W. Roberts. Director

ILLUSTRATIONS

Page

PREFACE 2 INTRODUCTION 7 TEST SITE DESCRIPTION 8

DEFINITION OF PENETPJ^TION 8

TEST IDENTIFICATION 10

INSTRUMENTATION 12

ATTACK 20S 16

ATTACK 20M 19

ATTACK 2 IN 22

ATTACK 26P 25

ATTACK 22A 29

ATTACK 22B 32

ATTACK 27T 37

ATTACK 23B ^1

ATTACK 29A 50

ATTACK 25D 52

ATTACK 24B 59

ATTACK 28D 64

ATTACK 30D 71

CONCLUSIONS 75

APPENDIX 76

ATTACK 2 OS 77

ATTACK 20M 78

ATTACK 2 IN 79

OTHER ATTACKS 80

ATTACK 22A 81

ATTACK 22B 82

ATTACK 27T 83

ATTACK 23B 84

1
PREFACE

The cooperation and active support of many individuals in several

organizations made the collection of these barrier penetration test

data possible. In particular, we wish to thank the U. S. Army , Mobility

Equipment Research and Development Center for providing the opportunity

to conduct the tests, and for providing overall test support including

photographic coverage. James W. Owen and Robert L. Barnard and the many

other MERDC participants were key contributors. Attack tooling and much

of the instrumentation was provided by the U. S. Army, Intelligence

Materiel Development Office, Fort Holabird, Maryland, ably represented

by Frank C. Veirs. Penetrations were accomplished by personnel from the

Naval Security Group under the direction of Richard F. Blackmon. R. S.

Koyanagi of the Vibration Section of the National Bureau of Standards

provided support in the collection of the vibrational disturbance data

and T. L. Quindry of the Applied Acoustics Section provided the

acoustical data shown in the appendix. The guidance and active participation of Marvin C. Beasley, Defense Nuclear Agency Task Officer for

this project is gratefully acknowledged.

2
ILLUSTRATIONS

Figure Title

1 Layout for Simulated Arms Rooms

2 Locations of Attack Areas on Simulated Arms Room

Test Facility

3 Data Collection Instruments

4 Attack 20S

5 Acoustical Disturbances Made by Hand-operated

Brace and Bit

6 Acoustical Disturbances from Electric Saber Saw

7 Vibrational Disturbances from Electric Saber Saw

8 Attack 20M

9 Acoustical Disturbances from Rotary Electric Saw

10 Vibrational Disturbances from Rotary Electric

Saw

11 Acoustical Disturbances from 3/4" Wood Bit Used

with 3/8" Variable Speed Electric Drill

12 Vibrational Disturbances from 3/4" Wood Bit and

Electric Drill

13 Attack 21N

14 Rotary Electric Saw, Acoustical

15 Rotary Electric Saw, Vibration Through Eight-foot

Transmission Path

16 Vibration produced by Handsaw Cutting Rafter

17 Interior View of Opening Produced by Attack 21N

18 Attack 26P

19 Acoustical Disturbances from Oxyacetylene

Cutting Torch

20 Vibration from Cutting Torch

3
Figure Title

21 Multiple Sweep of Acoustical Disturbances from

Breaking Glass Window

22 Breaking Glass Window with Bolt Cutters

23 Attack 22A

24 Acoustical Disturbance from Sledgehammer Prior

to Breakthrough

25 Vibrational Disturbances from Attack 22A

26 Acoustical Disturbance from Attack on Brick

Veneer

27 Vibration from Attack on Brick Veneer

28 Attack 22B

29 Acoustical Disturbance from Rotohammer Attack

on Cinder Block

30 Vibration from Attack on Cinder Block

31 Acoustical Disturbances from Cutting Torch

32 Vibrational Disturbances from Cutting Torch

33 Attack 27T

34 Vibration During Bolt-cutter Attack

35 Ambient Vibrational Background at Location 27T

36 Multiple Sweep of Acoustical Disturbances

Produced by Bolt Cutters

37 .

. Vibration from Sledgehammer Attack on Draw Bolt

38 Attack 23B

39 Acoustical Disturbance from Drilling

40 Vibrational Disturbance from Drilling

41 Acoustical Disturbance from Spalling

42 Vibration from Spalling

4
Figure Title

43 Abrasive Wheel Cutoff Saw Used in Attack 23B

44 Acoustical Disturbances from Abrasive Wheel Cutoff

Saw

45 Vibration from Abrasive Wheel Cutoff Saw

46 Opening Made by Attack 23B

47 Acoustical Disturbances from Sledgehammer

48 Vibration from Sledgehammer

49 Acoustical Disturbances from the Cutting Torch

50 Attack 29A

51 Vibration from Sledgehammer on Cinder-block Wall

52 Attack 25D

53 Acoustical Disturbances from Drilling Reinforced

Concrete

54 Vibration from Drilling Reinforced Concrete

55 Interior of the Wall with Spalling Nearly Complete

56 Multiple Sweep of Acoustical Disturbances Produced

by Spalling

57 Vibration from Spalling with Transducer Mounted

10' from Attack Point

58 Vibration from Spalling with Transducer Mounted

20' from Attack Point

59 Vibration from 20-pound Sledgehammer

60 Vibration from 10-pound Sledgehammer

61 Vibration from Rotohammer

62 Acoustical Disturbances from Spalling

63 Vibration from Spalling

5
Figure Title

64 Use of Tapered Punch in Attack 24B

65 Vibration from File

66 Acoustic Disturbances from Drilling on Vault

; Door

67 Vibration from Drilling on Vault Door

68 Acoustical Disturbances from Rocket Torch

69 Vibration from Rocket Torch

70 ; .V Comparison of Cuts Made by Rocket Torch (Wide)

and Oxygen-fed Electric Arc (Narrow)

71 Acoustical Disturbances from the Electric Arc

; " Torch

72 Vibration from the Electric Arc

73 Burning Bar ^felting a Hole Through Concrete

74 Acoustical Disturbance from Burning Bar Attack

on Concrete

75 Vibration from Burning Bar Attack on Concrete

76 Burning Bar Cutting Reinforcing Rod at

Location 24B

77 Acoustical Disturbance from Burning Bar Attack

on Expanded Metal

78 ; Vibration from Burning Bar Attack on Expanded

Metal

6
PENETRATION TESTS

ON

J-SIIDS BARRIERS

by

R. T. Moore

INTRODUCTION

The degree of protection that is afforded to computers, money or negotiable securities, weapons, classified materials, or other valuable

items, is dependent upon the effectiveness of the physical security

measures which are employed to safeguard them. Current physical

security measures are usually based on the concept of employing one or more barriers, such as fencing, a strong room or a vault to enclose a protected area coupled with one or more electronic sensors which are intended to detect penetration of the barrier (s) or any intrusion into

the protected area. Detection of barrier penetration or area intrusion

causes an alarm and initiates some form of reaction on the part of

guards, police or other forces. To be effective in safeguarding the

protected area, the time that is required for a potential intruder to

penetrate the barriers must be greater than the total time required for

detection of the penetration and the response of the reactionary force.

Thus, an evaluation of the effectiveness of a physical security system

requires, among other things, some basis for developing estimates of the

time which might be required to penetrate a given barrier.

This report describes the results of a series of penetration tests

which were made on three simulated arms rooms located at the U. S. Army

Mobility Equipment Research and Development Center (MERDC) test facility,

Woodbridge, Virginia, during a one week period beginning March 13,1973.

The objectives of these tests were to develop estimates of

(a) the times required to make man-passable penetration openings;

(b) the times required for the electronic intrusion systems with

which the simulated arms rooms were equipped to respond to the

penetration attacks;

(c) the acoustic, ultrasonic and vibrational disturbances produced

by the various attacks; and finally,

(d) (not reported herein) to evaluate the performance of the JointService Interior Intrusion Detection System (J-SIIDS) in detecting

these penetration attacks and to assess the vulnerability of this

system to countermeasures .—

Ij Intrusion Detection Test Report, J-SIIDS Equipment, Robert Barnard,

U. S. Army, MERDC.

7
TEST SITE DESCRIPTION

The simulated arms room facility consisted of a three-room

structure located inside of the 45' X 90' west wing of one of the Harry

Diamond Laboratories buildings at Woodbridge, Virginia. The general

arrangement of the structure is shown in figure 1. Room 1 was fabricated of wood with a double planking of nominal one-inch thick wood

siding over 2" X 4" studs and no interior finish. The flat roof was similarly planked over 2" X 6" rafters. The roof height was approximately 9' and was level with that of the other two rooms.

Room 2 had exterior walls of 8" cinder block with 5/8" reinforcing

bars inserted vertically in the cores of the blocks with a spacing of

about 14". The cores of the blocks were filled with mortar and three

1/8" steel wires were used as horizontal reinforcement in every second

course. One of the exterior walls had a single layer of block veneer

laid up with a one-inch air space between the veneer and the block and

tied to every second course of block with sheet metal ties.

Room 3 had walls of 8" concrete reinforced with 3/4" rod on 12"

centers vertically and horizontally. The room was equipped with a GSA

Class 6 vault door. The roof of this room and of Room 2 was of 5-1/2"

thick reinforced concrete with 1/2" reinforcing bars on 8" X 12"

centers.

These rooms had been constructed by MERDC in support of the J-SIIDS

development effort and were instrumented with appropriate components of

this intrusion detection system during the penetration tests. The rooms were intended to be representative of the broad range of

structural barriers which might be found in existing arms rooms.

DEFINITION OF PENETRATION

A barrier is considered to have been penetrated when an opening has

been made which is large enough for a small man to wriggle through. It

is generally accepted that an opening having an area of 96 square inches

with one dimension of at least 6" will meet this criterion. In these

tests, attack areas were marked out on the barriers in the form of

either an 8" X 12" rectangle or an 11.1" diameter circle as appropriate

to the attack tooling which was employed. In those instances where the

attack produced an opening larger than, or significantly different from

these sizes, its dimensions are reported.

8
9
TEST IDENTIFICATION

Each proposed target area for a penetration attack was assigned an alphanumeric identifier which was painted on the external surface of

the selected barrier adjacent to the perimeter of the planned opening.

It is used to label test data from each attack and is especially helpful

in identifying photographic records. The identifier consists of a number-letter-number sequence in which the first number indicates the

barrier to be attacked. The following letter indicates the area of

the attack and the general nature of the initial tooling used on that

area. The final number is a sequence number associated with changes in

tooling or to identify individual measurements. The sequence number is

used in connection with data from the instrumentation and does not

appear in the photographic records.

Letters designating initial tooling were selected from the following

list:

A. Sledgehammer

B. Rotohammer

C. Diamond Drill

D. Burning Bar

E. Linear-Shaped Charge

F. Demolition Saw

G. Pneumatic Jackhammer

H. Rock Melter

J. Water Jet

K. Battering Ram

M. Gasoline-Powered Rotary Saw

N. Electric-Powered Rotary Saw

P. Cutting Torch

Q. Electric Drill

R. Saber Saw

S. Brace and Bit

T. Bolt Cutters

Some deviation from this list of designators occurred when changes

in the test plan were occasionally made after the identifiers had been

painted on the barrier. Rather than delay the test series to repaint

the identifier, the testing proceeded using the original markings.

Figure 2 shows the locations of all of the attack areas.

10

INSTRUMENTATION

Acoustic and ultrasonic disturbances produced by the various attacls

were observed using a 1/4" microphone having a nominally flat frequency

response to above 50 kHz. This was mounted on a small tripod and

together with its preamplifier and power supply was positioned inside

the room involved during each attack. The distance from the microphone

to the inner surface of the area under attack ranged from a minimum of

about 6' to a maximum of about 12'. Since the variation in attenuation

over this distance range is less than the variation in sound pressure

levels which may result from reinforcement or cancellation caused by

reflections from the walls and corners of the room itself, no attempt

has been made to normalize the observed data or to compensate for minor

deviations in the frequency response of the microphone. All sound pressure levels (SPL)are expressed as dB reference a zero level of .0002 dynes

per square centimeter and, for the reasons noted above, should be

considered only as representative values.

Vibrational disturbances were picked up by piezoelectric transducers mounted on the interior surface of the room under attack. These

had a frequency response extending to over 100 kHz. Their associated

charge amplifiers were located nearby in a protective enclosure and were

coupled by a 50-ohm transmission line to the data recording position

which was external to the simulated arms rooms. The nominal separation

between attack point and vibration transducer is reported with the data

presented for each attack. Vibrational spectra are expressed in terms

of peak g values.

The transmission lines from the charge amplifiers and microphone

preamplifier were each 50' long and terminated at a selector switch box

arranged so that either one could be selected as the input to a real-time

spectrum analyzer. The output of the spectrum analyzer was displayed on

a storage tube oscilloscope and photographs were taken of samples of the

spectra of the disturbances. The data recording instrumentation was typically clustered outside the arms rooms adjacent to the attack

location as shown in figure 3

.

The spectrum analyzer was operated with a sweep width of 50 kHz, a sweep rate of 5 kHz per cm (on the display) , a sweep speed of 30 ms per

cm and a bandv7idth of 500 Hz. The vertical axis of the display showed

the spectral amplitude in a logarithmic mode with sensitivity of 10 dB

per cm and covered a dynamic range of 60 dB. The type of spectrum

analyzer used does not have memory; that is, it displays those spectral

components of the signal which are within its passband at the "instantaneous" center frequency of the sweeping passband. A single sweep provides a reasonably good representation of continuous signals such as from

a motor-driven tool or a cutting torch, but on intermittent signals, such

as hammer blows, many sweeps may be required to develop an estimate of

their spectrum over the full 50 kHz sweep width. This is because on one hammer blow the passband of the analyzer may be sweeping past the 5 kHz

region and on the next it may be sweeping past the 35 kHz region. Under

12
Figure 3. Data Collection Instruments

13
circumstances such as these, multiple sweeps were collected on the

storage tube oscilloscope prior to photographing them whenever the

attack duration was long enough for this to be feasible.

On some of the tests, peak sound pressure levels were also recorded

from a position outside of the arms rooms using a hand-held sound pressure level meter equipped with a 1/2" microphone. These observations

are reported as external SPL values (dB) together with the distance from

the attack point to the observer.

During a portion of the tests, audio frequency disturbances were

picked up using a one-inch microphone within the room under attack.

These data were recorded on magnetic tape and subsequently analyzed and

reduced to 1/3 octave bandwidth sound pressure levels in the 20 to

20,000 Hz frequency bands. The resulting tabulations are presented in

the appendix.

Throughout the test sequence, each penetration that was made into

one of the rooms was covered over by an aluminum panel before the next

penetration was begun. The aluminum panels were held in place with

4" wide pressure sensitive tape and were intended to reduce the level of

acoustical disturbance within the room resulting from normal test crew

activities outside the room.

Timing information on the penetration tests was derived from a variety of sources including a hand-held stopwatch, a strip chart event

recorder and by manual control of the application of power to a selfstarting electric clock with a a^eep-second hand. A test plan objective

was to try to accumulate three time values associated with each attack:

(a) working time, (b) elapsed time, and (c) time from start of attack

until the first J-SIIDS alarm. Working time is considered that amount of

time during which the attack tooling is being actively employed. It does

not include intervals required for changing tools, selecting the next

place to drill a hole, changing to a fresh operator when the first

attacker becomes fatigued, or similar interruptions to an attack which

would be necessary with even a skilled team of determined attackers.

Elapsed time was planned to take into account these additional factors.

For a number of reasons it was not always possible to. obtain a value for

elapsed time which could be considered representative of what could be

accomplished by a determined team of attackers. Where values were

obtained which were considered nonrepresentative, they are omitted from

this report.

The accuracy of all of the timing information was also slightly degraded by the fact that nearly all of the attacks were purposely stopped

on from one to several occasions so that changes could be made in the

sensitivity settings of the J-SIIDS equipment to permit the development

of information on the gain control settings required for response to the

various attacks. Thus, in most instances, attack time and elapsed time

values represent the sum of a number of discrete time increments. There

is a probable uncertainty on the order of at least +1 second in the

14
determination of each such increment. The uncertainty in the length of

time between the start of the attack and the initiation of the first

alarm is also believed to be about one second.

15
ATTACK 20S

The first attack was on the wooden wall of Room 1. A hand brace

with 1" wood bit was used to make two holes in diagonally opposite

corners of the rectangular perimeter outline. Then an electric saber saw with a 6" course-toothed blade was used. The blade was inserted in

each hole and two cuts were then made outward to each of the remaining

corners of the rectangle freeing the central plug (see fig. 4). A

vibration transducer was mounted on the inte rior of the wall at a distance of 3' from the center of the opening.

The first hole required 19 seconds working time. The second hole was aborted after 28 seconds when the lead screw of the bit entered a crack between plarks of the inner layer and the bit would not feed. A

new hole was then started and was completed 16 seconds later. A sample

of the acoustical disturbances is shown in figure 5. The vibrational

disturbances were not noticeable above the ambient vibrational backgromtl.

Sawing required 45 seconds with acoustical and vibrational spectra as shown in figures 6 and 7 , respectively.

In this attack, the total working time was 1.33 minutes, the

elapsed time was 1.55 minutes, and the first J-SIIDS alarm occurred 27

seconds after the attack was started.

Figure A. Attack 20S

16
25 50

Frequency kHz

Figure 5. Acoustical Disturbances Made by

Hand-operated Brace and Bit

db

Frequency kHz

Figure 6. Acoustical Disturbances

Electric Saber Saw

17

from
Figure 7,

25

Frequency kHz

Vibrational Disturbances

from Electric Saber Saw

50

18
ATTACK 20M

Location 20M was adjacent to 20S and centered 3' from the unchanged

vibration transducer position. A gasoline-powered rotary saw had been

scheduled for use in this attack. Because of mechanical problems, an electric-powered rotary handsaw with a 7-1/4" carbide-tipped blade was substituted and was used to make A cuts along the sides of the rectangular opening as shown in figure 8 . Then the plug was knocked out

with one blow from a sledgehammer. The working time was 1.30 minutes,

the elapsed time 1.62 minutes, and the first J-SIIDS alarm occurred

5 seconds after the attack started. Acoustical and vibrational disturbances are shox^m in figures 9 and 10 .

Figure 8. Attack 20 M

Following attack 20M, a brief test was made to estimate the disturbances likely to be produced by a power-driven wood bit. This was accomplished by drilling sample holes in the area between the previous

two attacks. A 3/4" wood bit was used in a 3/8" variable speed

electric drill. Acoustical disturbances are shown in figure 1 1 and

vibrational disturbances in figure 12.

19
0 25 50

Frequency KHz

Figure 9. Acoustical Disturbances from

Rotary Electric Saw.

0 25 50

Frequency kHz

Figure 10. Vibrational Disturbances from

Rotary Electric Saw

20
0 25 50

Frequency kHz

Figure 11. Acoustical Disturbances from

3/4" Wood Bit Used with 3/8"

Variable Speed Electric Drill

Frequency kHz

Figure 12. Vibrational Disturbances from 3/4"

Wood Bit and Electric Drill

21
ATTACK 2 IN

Location 21N was centered on the roof of Room 1 at a distance of 8'

from the vibration transducer. The vibration transducer was mounted on an interior wall of the room at a point 2' below the roof. Thus, the

transmission path included 2' of wall and 6' of roof of the structure.

The attack location was chosen so that the opening would straddle one of

the 2" X 6" wooden rafters so that this would have to be cut in two

places to complete the penetration. A 1-1/2 horsepower electric saw with a 7-1/4" combination blade was used to cut through the planking

along the rectangular perimeter of the opening in 0.5 minute. The

rafters were then cut with a carpenter's handsaw in 0.96 minute, as shown in figure 13 . The total working time was 1.47 minutes with

elapsed time of 1.73 minutes. The initial J-SIIDS alarm occurred 5

seconds after the attack began.

Figure 13. Attack 21N

Samples of the acoustical, figure 14 , and vibrational, figure 15 , disturbances from the electric saw were quite similar to those observed

from the different electric saw and blade used in Attack 20M.

22
The vibrational disturbances produced by the handsaw are shown in figure 16 . The handsaw produced a peak SPL of 98 dB observed at a distance of approximately 5*.

The opening produced by the attack is shown

134

114 -

in figure 17

.

db

94

74 ~

54

1 " ;

-J

t

-

1

! M (

1 (IN

jt.'.. ; : ,

! 1 1 1'

/

i i

- t -f~

'» :

t

4-

Figure 14.

25 50

Frequency kHz

Rotary Electric Saw, Acoustical

1.0 -t

0.1

-0 1 -i

.001 —|. A.. (.^^. . _

.0001-1

I 0 25

Frequency kHz

Figure 15. Rotary Electric Saw, Vibration

through Eight-foot Transmission Path

23
Figure 17. Interior View of Opening

Produced by Attack 21N

24
ATTACK 26P

Location 26P was centered on a 3/16" thick expanded steel grill

which was fastened to a window-like opening in Room 1, as shown in

figure 18 . The attack involved the use of an oxygen-acetylene cutting

torch to cut out along the targeted rectangular perimeter. The torch was used with a No. 5 cutting tip and oxygen pressure of 30 p.s.i. and

acetylene pressure of 12 p.s.i. The cutting required 3.05 minutes

working time and 3.14 minutes elapsed time. A J-SIIDS alarm was initiated within 5 seconds after the torch was ignited and before the

first cut was started.

The vibration pickup was located on the wall of Room 1 approximately

6' from the grill and in the same position that it occupied during the

earlier attacks.

Samples of the acoustical disturbances are shown in figure 19 and of

the vibration disturbances in figure 20

.

Figure 18. Attack 26P

25
0 25 50

Frequency kHz

Figure 19. Acoustical Disturbances from

Oxyacetylene Cutting Torch

1.0

Frequency kHz

Figure 20. Vibration from Cutting Torch

26
To conclude the activities in Room 1, another unscheduled test was

performed. This involved breaking the glass in a window located at the

west end of the room and cutting a coarse wire mesh attached rather

flimsily to the inside of the window frame. The glass was quickly

broken with a hammer and samples of the acoustic disturbances are shown

in the multiple trace photograph of the spectrum analyzer output in

figure 21. When a bolt cutter was used to cut the wire mesh, see figure 22 , it fell off of the window frame on the second or third cut so no actual total times are available. It is estimated that this

penetration could have been completed in less than 30 seconds if the

mesh had remained in place.

134

114

db

25

Frequency kHz

Figure 21. Multiple Sweep of Acoustical

Disturbances from Breaking

Glass Window

27
Figure 22. Breaking Glass Window

with Bolt Cutters

28
ATTACK 22A

Attack 22A was conducted on Room 2 on a wall made up of a layer of

brick veneer over 8"-thick cinder block. The brick was spaced out from

the cinder block 1" and tied to every second course of block by metal

ties. The block was reinforced with 5/8" diameter rod inserted

vertically in the cores on approximately 14" centers. The cores of the

block were presumably to have been filled with mortar. After the attack,

examination showed the mortar filling to be rather loose and crumbly

with a large number of voids.

The vibration transducer was mounted on the interior surface of the

wall at a distance of 5' from the center of the target area.

The attack was begun with a 10-pound sledgehammer and 28 blows

produced an oversize opening through the brick veneer. These produced

a peak SPL of 94 dB as observed at a distance of 10' outside of the

room. This was followed by 16 blows with a 12-pound sledgehammer, see figure 23, and 28 blows with a 10-pound sledgehammer which produced a break measuring approximately 2" X 4" through the cinder block. Twelve

more blows, with the end of the 10-pound sledgehammer being used as a ram, enlarged the opening to 10-1/2" X 11-1/4". This required a total

of only 64 blows with a working time of only 2.12 minutes. By chance,

the opening did not intercept one of the infrequent reinforcing bars

so a cutting torch was not required. Samples of the acoustical disturbances prior to breakthrough are shown in figure 24 and of the

vibrational disturbances in figure 25. Both of these figures show

multiple sweeps of the spectrum analyzer.

The first J-SIIDS alarm occurred 5 seconds after the attack was

started.

29
t

Figure 23. Attack 22A

9 25 50

Frequency kHz

Figure 24. Acoustical Disturbance from

Sledgehammer Prior to Breakthrough

30
25

Frequency kHz

Vibrational disturbances

from Attack 22A

31
ATTACK 22B

Attack 22B occurred on the same wall as 22A and at a location

centered 18" from the vibration transducers. This attack employed a rotohammer and 1-1/2" toothed-chisel to cut along the perimeter of the

targeted opening. Mortar joints were prime targets to the extent that

they reasonably corresponded with the perimeter. It required 4.87

minutes to clear a somewhat oversize opening through the brick veneer. This activity produced a SPL of 95 to 100 dB as observed at a distance

of 12' and produced acoustical disturbances inside the room as shown in

figure 26 . Vibrational disturbances are shown in figure 27

.

Then the cinder block was attacked through the opening in the brick

veneer as shown in figure 28. It took 3.5 minutes with the rotohammer

and approximately 0.25 minute with a sledgehammer to clear the block

away making a suitably-sized hole containing a single reinforcing rod.

Acoustical disturbance produced by the rotohammer are shown in figure

29 and vibrational disturbances in figure 30 .

Finally, the reinforcing rod was cut in 1.1 minutes with an oxygen

acetylene torch using a No. 5 tip, oxygen pressure of 30 p.s.i. and

acetylene pressure of 12 p.s.i.. The torch produced a peak SPL of

82 dB at 10'. Acoustic disturbances are shown in figure 31 and vibrational disturbances in figure 32 .

The total working time for this attack was 9.71 minutes and the

first J-SIIDS alarm occurred 5 seconds after the attack started.

The opening produced was 13-1/4" high, 6-1/2" wide at the bottom,

and 8-1/2" wide at the top.

32
134

114 —

db

94 —

74 —

Frequency kHz

Figure 26. Acoustical Disturbance from

Attack on Brick Veneer

10

I —

o.»—

.0\ —

.001 mmL\ iiniiihHniHBi ! , 25

Frequency kHz

50

Figure 27. Vibration from Attack on Brick Veneer

33
Figure 28. Attack 22B

Frequency kHz

Figure 29. Acoustical Disturbance from Rotohammer

Attack on Cinder Block

34
.001 -t

0

Frequency kHz

50

Figure 30. Vibration from Attack on Cinder Block

134 -]

114

db

Frequency kHz

Figure 31. Acoustical Disturbances from

Cutting Torch

35
g

Figure 32. Vibrational Disturbances

from Cutting Torch

36
ATTACK 27T

Location 27T was a pass window screened with l/8"-thick expanded

metal and backed by a metal-clad wooden half door which was hinged on

one side and secured to the frame by a draw bolt on the other. The

targeted opening was located on one edge of the grill centered over the

draw-bolt position. As shown in figure 33 , 3/8" capacity bolt cutters

were used to cut 3 sides of the perimeter of the opening leaving a flap

of expanded metal which could be bent back out of the way. Two blows

with the sledgehammer were then sufficient to break off the draw bolt

permitting the half door to swing open. The working time for this

attack was 3.25 minutes and the elapsed time 3.58 minutes. The first

J-SIIDS alarm occurred 7 seconds after the attack began.

During this attack, the vibration transducer was located in the same position as in Attacks 22A and 22B and at a distance approximately 8'

away. Vibrational disturbances observed during the bolt cutter attack

are shown in figure 34 which does not materially differ from the background disturbance level prior to the attack as shown in figure 35 . A

multiple sweep of acoustical disturbances produced by the bolt cutters

is shown in figure 36 . The vibrational disturbance from the sledgehammer breaking the draw bolt is shown in figure 37.

37
Figure 33. Attack 27T

38
10 -1

0.1

.01

.001

.ooo^

0 25

Frequency kHz

Figure 34. Vibration During Bolt Cutter Attack

1.0

0.1

.01

.001

.0001- iiawg

Figure 35,

Frequency kHz

Ambient Vibrational Background

at Location 27T

39
114

Figure 36. Multiple Sweep of Acoustical

Disturbances Produced by Bolt

Cutters

10

0.1 —

.01 —

.001 25

Frequency kHz

Figure 37. Vibration from Sledgehammer

Attack on Draw Bolt

40
ATTACK 23B

Location 23B was on the roof of Room 2. The roof was 5-1/2" thick

concrete reinforced with 1/2" bars located in the approximate center of

thickness and spaced 8" apart in one direction and 12" apart in the

other direction. An 8" X-12" opening perimeter was laid out and hole

locations were spotted at each corner, in the center of the rectangle

and midway on each 12" side. Using the rotohammer, 1" diameter holes

were drilled to a depth of 3-1/2" at each of these 7 locations as shown

in figure 38 . A 1" bull-point punch was then used in each hole and

with a 12-pound sledgehammer the interior 2" of concrete was spalled

away. At this point, inspection inside the room revealed the fact that

the targeted opening straddled an electrical conduit, previously con- cealed in the concrete, which supplied power to Room 3. Since this

power would be needed in connection with later tests, the targeted

opening was relocated by moving it 8" along its short dimension. This

required drilling and spalling out 4 new holes and the time for this was

not included in the measurements reported for this attack. It took 151

seconds or 2.52 minutes to drill the 7 original holes. Since 24.5 linear inches of material was drilled in these 7 holes, the average drilling

rate for the 1" diameter bit was 6.16 seconds per inch. Samples of the

acoustical disturbances are shown in figure 39 and the vibrational

disturbances in figure 40. The latter were obtained with the transducer mounted on the inside of the concrete roof at a distance of 8'

from the center of the opening.

Spalling out the concrete below the bottoms of the holes required

2.92 minutes and produced a peak SPL of 91 dB observed 25' away from the

attack location. Multiple sweep photographs of the acoustical spectra

are shown in figure 41 and the vibrational spectra in figure 42 .

41
Figure 38. Attack 23B

42
0 25 50

Frequency kHz

Figure 39. Acoustical Disturbance

from Drilling

0 25 50

Frequency kHz

Figure 40. Vibrational Disturbance

from Drilling

A3
0 25 50

Frequency kHz

Figure 41. Acoustical Disturbance

from Spalling

g

0 25 50

Frequency kHz

Figure 42. Vibration from Spalling

44
Next, as shown in figure 43, a 5-horsepower gasoline-powered saw equipped with a 12" diameter abrasive cutoff wheel was used to cut a groove around the perimeter of the relocated opening. This took 5.06

minutes working time and it was necessary to replace the cutoff wheel

about midway through this activity because of wheel wear. In addition,

it was necessary to vacate the wing of the building housing the arms rooms after each of the 4 perimeter cuts while the dust and exhaust funes were cleared away by fans. These latter time intervals were not incluied

in the calculation of elapsed time.

Outside of the room the abrasive wheel cutoff saw produced 105 dB

SPL at a distance of 25'. Samples of the acoustical spectrum within the

room were lower and are shown in figure 44 and the vibrational spectrum

are shown in figure 45 . Note how the latter peaks in the 15 to 35 kHz

frequency range.

Figure 43. Abrasive Wheel Cutoff Saw

Used in Attack 23B

45
134

IK

db

94 —

74 -

Frequency kHz

Figure 44. Acoustical Disturbances from

Abrasive Wheel Cutoff Saw

10 —

I

.001 O .2525 50

Frequency kHz

Figure 45. Vibration from Abrasive

Wheel Cutoff Saw

46
The cut made by the abrasive wheel saw around the perimeter of the

opening penetrated to a depth of between 2" and 3". This left about an Inch of concrete between the bottom of the cut and the top of the previously spalled Interior area. It was hoped that the remaining plug

could be broken out by a direct sledgehamm.er assault, but, when 50

seconds of effort with this tool produced only moderate spalling on the

surface, it was decided to drill two more holes with the rotohammer.

These were made in 18 seconds and then the sledgehammer attack was resumed. This time it was quite successful and only 23 more seconds were

required to clear the concrete from the opening exposing the reinforcing

rods for cutting as shown in figure 46 . Acoustic disturbances

produced by the sledgehammer are shown in figure 47 and vibrational

disturbances in figure 48. Both of these are photographs of multiple

sweeps of the output of the spectrum analyzer.

The reinforcing rod was cut in 1.42 minutes using a No. 5 tip,

25 p. s.i. oxygen pressure and 5 p.s.i. acetylene pressure. Acoustical

disturbances are shown in figure 49 which exhibits the typical flat

spectrum of a cutting torch.

The total working time to produce the final 9" X 12-1/2" opening was

13.58 minutes and the calculated elapsed time was 17.0 minutes. The

first J-SIIDS alarm occurred 5 seconds after the attack was started.

The relatively long working time required in this attack was undoubtedly due, in part, to the rather awkward working conditions

associated with this location. The roof of Room 3 was only about 3-1/2'

below the ceiling of the building housing the simulated arms rooms. This

low clearance forced the attackers to work from a sitting or kneeling

position and severely limited their freedom of movement and the effective

application of their tools. Later attacks on the 8" thick reinforced

concrete walls of Room 3 provide some indication of the magnitude of the

influence of this constrained working space.

47
Figure 46. Opening Made by Attack 23B
10 —

>

0.1

.01

.001

mm

1 1 1 1 1 I 1 1

! M ! T t t

• niiiHumi

M m nHpnna,

25 50

Fre<5uency kHz

Figure 48. Vibration from Sledgehammer

134

114 —

db

Figure 49. Acoustical Disturbances from

the Cutting Torch

49
ATTACK 29A

The last attack on Room 2 was made on the un-veneered cinder-block

wall. The attack was with a 12-pound sledgehammer, as shown in figure

50 , and required 47 blows and 1.26 minutes. No reinforcing bars were

encountered, however, two horizontal reinforcing wires were exposed and

these were cut with a No. 0 bolt cutter in 4 seconds. The total working

time was 1.32 minutes and the elapsed time was 1.52 minutes. The first

J-SIIDS alarm occurred 8 seconds after the attack began. Vibration

disturbances picked up by a transducer mounted on the wall 4-1/2' from

the center of the attack area are shown in figure 51 .

Figure 50. Attack 29A

50
25

Frequency kHz

Figure 51. Vibration from

Sledgehammer on Cinder-block Wall

51
ATTACK 25D

This test was Identified as 25B on the test plan but the physical

location was stenciled as 25D and it will hereinafter be referenced by

that identifier to be consistent with the photographic coverage. The

attack was made on one of the 8" thick reinforced concrete walls of

Room 3. It involved drilling a pattern of 1" diameter holes partially

through the concrete to predetermined depths, then spalling out concrete

on the interior using a 1" bull-point punch and sledgehammer. Initial

spalling was from the deepest holes and after the material was cleared

out behind them the attack shifted to the shallower holes and finally

to the surface of the remaining plug. Finally, reinforcing would be

cut if necessary. As developed, the opening exposed but did not

straddle a reinforcing bar and cutting was not necessary in this attack.

The hole pattern that was laid out was in the form of two concentric

circles; the outer circle approximately 11-1/2" in diameter and the

inner circle approximately 5-3/4" in diameter. Locations for the six

holes were laid out at 60 increments on the outer circle and for three

holes at 120° increments on the inner circle. These nine holes were to

be drilled 5" deep. Nine more locations were then laid out midway

between those of the original group and marked for drilling to a depth

of 2-1/2". Figure 52 shows the hole pattern as laid out.

Using the rotohammer and 1" drill, it took 7.88 minutes to drill the

nine holes 5" deep. This represents 45 linear inches and an average

rate of 10.5 seconds per inch. There was a range of from 38 to 70

seconds of time required for individual holes but several were drilled

in 42 to 47 seconds. The nine 2-l/2"deep holes required 3.27 minutes fcr an average rate of 8.7 seconds per inch. The overall average drilling

rate was 9.91 seconds per inch.

Typical SPL values of 108 to 110 dB were observed at a distance of

7'. Acoustical disturbances inside Room 3 are shown in figure 53.

Vibrational disturbances recorded from a transducer mounted on the wall

10' from the attack point are shown in figure 54 .

52
Figure 52. Attack 25D

Frequency kHz

Figure 53. Acoustical Disturbances from

Drilling Reinforced Concrete

53
0 25 50

Frequency kHz

Figure 54. Vibration from Drilling

Reinforced Concrete

Spalling the concrete from the interior beneath the holes was accomplished using a 10-pound sledgehammer and 1" diameter bull-point

punch and required 6.98 minutes. Figure 55 shows the interior of the

wall with spalling nearly complete. Figure 56 is a multiple sweep

photograph of the acoustical disturbances which were produced within

Room 3. Outside SPL readings 99 to 102 dB were observed at a distance

of 8'. Typical vibrational disturbances observed with a transducer

located on the same wall as the attack and at a distance of 10' are shown in figure 57 . A second tranducer mounted on the opposite wall

of Room 3 with a transmission path length of approximately 20' yielded

the spectrum shown in figure 58.

54
After the spalling was completed, the remaining plug was broken out

using a 20-pound sledgehammer for 23 seconds and a 10-pound sledgehammer

for 13 seconds. Multisweep vibrational data from the 20~pound hammer is

shown in figure 59 and from the 10-pound hammer in figure 60 . In

both instances the transducer was 10' from the attack point. Note the

higher g values developed by the 10-pound hammer. This is attributed to

the higher velocity which could be developed in swinging this lighter

hammer

.

The total working time required to complete penetration 25D was

18.73 minutes. The first J-SIIDS alarm occurred 5 seconds after the

attack began.

Figure 55. Interior of the Wall with

Spalling Nearly Complete

55
0 25 50

Frequency kHz

Figure 56. Multiple Sweep of Acoustical

Disturbances Produced by Spalling

0 25 50

Frequency kHz

Figure 57. Vibration from Spalling with

Transducer mounted 10' from

Attack Point

56
.00> mmmURIm

1 ma

25

Frequency kHz

50

Figure 58. Vibration from Spalling with

Transducer Mounted 20' from

Attack Point

10

I —

O.J —

.01

.001

_

1

• ; i. 1 T"

25

Frequency kHz

Figure 59. Vibration from 20-pound Sledgehammer
58
ATTACK 24B

Attack 24B was similar in concept to 25D but employed a fever number

of smaller diameter holes to prepare for spalling. The size of the

chunks of concrete initially spalled out in Attack 25D led to the con- viction that more ho^es had been drilled than were necessary. Also,

since earlier tests— had shown that drilling rate with the rotohammer is

dependent upon the volume of material removed in the case of hole

diameters of 1" or less, drilling 3/4" holes would be appreciably faster

than the 1" holes in Attack 25D. Whether or not a 3/4" diameter bullpoint punch would hold up under the sledgehammer was not known.

The hole pattern selected consisted of eight holes equispaced

around the perimeter of a circle 11-1/2" in diameter. Alternate holes

were drilled 5" and 3-1/2" deep. A single 4" deep hole was drilled at

the center of the circle. The rotohammer with 3/4" bit completed this

38 linear inches of drilling in 2.62 minutes at an average rate of 4.13

seconds per inch. SPL values of 104 dB were observed at 8' and 112 dB

at 2' distance. Vibrational disturbances as observed with the transducer

moxmted on the interior of the wall at a distance of 5' from the center

of the opening are shox-m in figure 61 .

Spalling out the bottoms of the drilled holes was accomplished V7ith

the 3/4" diameter bull-point punch and 12-pound sledgehammer. It took

1.42 minutes and 63 hammer blows on the 5" deep holes followed by 1.26

minutes and 58 blows for the 3-1/2" deep holes and 0.2 minutes and

9 blows for the 4" deep center hole. Samples of acoustic disturbances

are shown in figure 62 and vibrational disturbances in figure 63 .

The 3/4" diameter bull-point punch performed satisfactorily in

spalling out the first few holes. Then it received a glancing blow from

the sledgehammer which produced a very slight bend about midway along the

length of the punch. Subsequent hammer blows increased this bend and it

became necessary to try to straighten the punch after each subsequent

hole was spalled out. The marginal durability of the 3/4" punch could

easily be bolstered with a few extra spare punches.

Ij NBSIR 73-101, Penetration Resistance Tests of Reinforced Concrete

Barriers, by R. T. Moore, Interim Report for Period October 31 - November 3, 1972, prepared for Defense Nuclear Agency, Washington, D.C.

20305.

59
0 ; 25 50

Frequency kHz

Figure 61. Vibration from Rotohammer

134 —

1

0 25 50

Frequency kHz

Figure 62. Acoustical Disturbances from Spalling

60
10 -1

Frequency kHz

Figure 63. Vibration from Spalling

61
The remaining plug in the center of the hole was now held in place

by a perimeter ring of un-spalled concrete which ranged from 3-1/2" to 5"

in thickness and it was expected that this could be rather quickly broken

out. This did not prove to be the case. An initial breakthrough was produced in 2.56 minutes with a 20-pound sledgehammer, but, after another

1.07 minutes, it was apparent that the rate of enlargement was not very

fast and an alternative strategy was adopted as shown in figure 64. A

tapered punch with a maximum diameter of 1-1/4" was driven into each of

the 8 perimeter holes. This was quite effective in spalling the remaining

concrete between the holes and the broken out center of the plug. It

required 1.53 minutes and 66 blows from the 10-pound sledgehammer to

complete the spalling from the perimeter holes. This was followed by

0.25 minute with the sledgehammer alone to break off a few remaining

projecting points.

A single reinforcing bar was encountered in making this penetration.

It was decided to defer cutting this until a later test using the burning

bar. At that later time, the bar was cut in two places in 0.40 minute.

The total working time on Attack 24B was 11.31 minutes. The first

J-SIIDS alarm occurred 5 seconds after the attack was started.

Although the time here was only about 60 percent of that required

for Attack 25D, it could probably be further reduced to about 10 minutes.

The 3.63 minutes of sledgehammering the central plug to make initial

breakthrough could probably be reduced to about 2.5 minutes by drilling

three central holes configured as an equilateral triangle with sides

about 5" long. If their depth was 2-1/2", the calculated drilling time

would be .51 minute, spalling time with the bull-point punch is estimated

to take about 1.0 minute and then probably central breakthrough could

have been accomplished with the sledge in about another minute.

62
Figure 64. Use of Tapered Punch

in Attack 24B

63
ATTACK 28D

Location 28 was a GSA Class 6 security vault door. Initial plans

were to attack this with a burning bar but the plans were changed when

the opportunity arose to test a portable rocket-powered cutting torch.

Two approaches to making penetrations in this barrier were contemplated.

The first involved making a small opening at a point which would permit

the bolt-work blocking mechanism to be forced out of the way and permit

the bolts to be withdrawn from their locked position by operating the

vault door handle. The second involved making a 96 square inch circular

cut through the door itself at an area where minimum resistance would

be expected to be encountered.

Prior to pursuing either of these approaches, it was necessary to

adjust the latch of the inner grilled day-door of the vault. In the

process a rattail file was used to enlarge a bolt hole on the latch

bracket which was mounted on the inner steel door frame. A vibration

transducer had been mounted on the door frame about 20" away from this

bracket and the vibrational disturbances produced by the filing are shown in figure 65 .

Next, because drilling could be used to attack the bolt-work

blocking mechanism, a sample hole was started in the appropriate area

to provide an opportunity to collect acoustical and vibrational

disturbance data. A 9/32" high-speed steel bit was used in a 3/8"

variable speed electric drill. Multiple sweeps of the resulting

acoustical data appear in figure 66 and vibrational data in figure 67 . The vibrational transducer was on the inner frame of the vault door and

the microphone was within the vault with the door closed, of course.

On the outside, SPL values of 80 dB were observed with the drill running

at low speed and 87 to 88 dB at high speed at a distance of 3'.

64
g

Frequency kHz

Figure 65. Vibration from File

Frequency kHz

Figure 66. Acoustic Disturbance from

Drilling on Vault Door

65
0 25 50

Frequency kHz

Figure 67. Vibration from Drilling

on Vault Door

66
Next, the portable cutting torch (rocket) was used to attack the area of the vault door over the bolt-work blocking mechanism. After

74 seconds it appeared unlikely that this attack could be successfully

completed with the torch and a circular cut was immediately started in

another area of the door. In the remaining 99 seconds, before the

torch's fuel was consumed, an 80° arc of an 11.3" diameter circle was

cut in the 1/4" thick mild steel plate. The total burning time of the

torch was 2.88 minutes. Acoustical disturbances are shown in figure

68 and vibrational disturbances in figure 69

The portable rocket torch was judged to be a suboptimal choice for use in an attack against the bolt-work blocking mechanism. The particular area involved is protected by 1/4" of mild steel, 3/8" of hard

drill-resistant steel and 1/2" of stainless steel plate. During the

74 seconds that it was used against these, a hole was melted through

the mild steel and partially through the drill resistant steel. This

attack was abandoned at that point because it appeared likely that it

would weld the bolt-work blocking mechanism in place if it were continued. A more concentrated and higher temperature heat source is

preferred for this particular type of attack. On the circular cut, the

80 arc represents a cut length of 7.89" in the 1/4" mild steel. This

is a cutting rate of 12.5 seconds per inch. This is comparable to the

cutting rate of an oxygen-fed electric arc torch on the same material,

but at this rate, three of the rocket cartridges would be required to

make an opening of the necessary diameter in the 1/4" mild steel outside

of the door. This would require an estimated 7.5 minutes of working

time and it would still be necessary to penetrate the thinner inside

cover of the door. Figure 70 shows cuts made by the rocket torch and

by the oxygen-fed electric arc which produced a much narrower cut.

On the assumption that the rocket torch might have annealed the

drill-resistant plate, drilling was resumed after the door had cooled

off to where it did not represent a burn hazard to the operator. This was continued for 3.55 minutes and then abandoned in favor of an oxygen-fed electric arc torch attack. The electric arc was used for

5.65 minutes to make a hole through which the bolt-work blocking

mechanism could be accessed. Multiple sweeps of the acoustical

disturbances produced by the arc are shown in figure 71 and the

vibrational disturbances in figure 72 .

A 4" long cut was also made in the 1/4" mild steel door cover to

establish an estimate of its cutting rate. The 4" cut took 48 seconds

for an average rate of 12 seconds per inch.

Finally, the bolt-work blocking mechanism was forced using tooling

which was worked through the opening produced by the electric arc. The

time required for this activity was 8.0 minutes. The total working time

required to release the bolt work was 18.27 minutes.

67
Figure 68,

Frequency kHz

Acoustical Disturbances

from Rocket Torch

10 —

t

0.« —

.0« —

.001 25

Frequency kHz

50

Figure 69. Vibration from Rocket Torch

68
Figure 70. Comparison of Cuts Made by

Rocket Torch (Wide) and Oxygenfed Electric Arc (Narrow)

69
0 25 50

Frequency kHz

Figure 71. Acoustical Disturbances

from the Electric Arc Torch

g

Frequency kHz

Figure 72. Vibration from the Electric Arc

70
ATTACK 30D

A burning bar was used to make a single hole in the 8" thick con- crete wall of Room 3 as shown in figure 73 . It took .73 minute and

used 40" of bar with the oxygen pressure at 160 p.s.i. Acoustical

disturbances are shown in figure 74 and vibrational disturbances in

figure 75. The vibration transducer was mounted on the inner surface of

the wall at a distance of two feet from the attack point.

The first J-SIIDS alarm occurred when the bar penetrated the inner

surface of the wall.

As a further demonstration of the burn bar, the aluminum panel

covering the opening previously made in Attack 24B was removed and re- placed by a 3/16" thick expanded steel grating attached to the outside

of the wall. With oxygen pressure at 100 p.s.i., the steel grating was

cut along the perimeter of the previously made opening in 1.52 minutes.

The reinforcing rod, left intact in the opening until this time, was

then cut in 0.4 minute as shown in figure 76 . J-SIIDS alarms were

produced by the oxyacetylene torch flame used to ignite the burning bar.

Acoustic disturbances produced by the burning bar are shown in

figure 77 and vibrational disturbances in figure 78 , The vibrational transducer was located on the inner wall of Room 3 five feet from

the 24B opening.

Figure 73. Burning Bar Melting a Hole

through Concrete

71
0 25 50

Frequency kHz

Figure 74. Acoustical Disturbance from

Burning Bar Attack on Concrete

0 25 50

Frequency kHz

Figure 75. Vibration from Burning Bar

Attack on Concrete
Figure 76. Burning Bar Cutting

Reinforcing Rod at

Location 24B

73
Frequency kHz

Figure 78. Vibration from Burning Bar

Attack on Expanded Metal

74
CONCLUSIONS

The observed penetration times ranging from 1.3 minutes for a double-planked wooden wall to 18.27 minutes for a GSA Class 6 vault

door resulted from the use of portable, readily available tooling, manned

by operators who worked willingly and purposefully but who obviously

could not be motivated to the same extent as the would-be intruder team

who might stand to gain or lose a great deal depending on the speed and

vigor with which they pursued their attack. Such a team could probably

reduce each of the observed penetration times by at least 10 percent

and perhaps in some instances by as much as 50 percent.

All of the attack techniques that were used produced acoustical or vibrational or both types of disturbances which are readily detectable

and were, in fact, detected by the J-SIIDS equipment. For adequate

safeguarding of any area, the intrusion alarm system must be backed up

with guard, police, or other reaction forces having response times

which are less than the times required to complete a penetration. This

response time should be less than one minute for situations where the

barrier structures are similar to those in Rooms 1 and 2, and should be

less than 10 minutes in the case of a vault structure similar to Room 3; even shorter response times would be necessary to safeguard against more

powerful penetration attacks such as the use of explosives.

75
APPENDIX

During some of the tests, audio frequency disturbances were picked

up using a one-inch microphone located within the room under attack.

These data were recorded on magnetic tape and subsequently reduced to

1/3 octave bandwidth sound pressure levels in the 20 to 20,000 Hz

frequency bands. The resulting tabulations are presented in this

appendix grouped by attack identification designators.

These data should be considered as representative values rather

than absolute as there were several uncontrolled variables associated

with the data acquisition. These include the unknown acoustical

characteristics of the simulated arms rooms and the variations in

transmission path lengths between the microphone and the attack points.

These factors could have an influence on the order of -H) dB on any of

the tabulated values.

76
ATTACK 2 OS

One-third octave sound pressure levels, dB

. Frequency

Band 1 2 3 4 —

20 70 40 81 71

25 61 61 74 79

31 64 63 75 99

40 56 56 65 98

50 53 52 63 84

63 50 51 58 80

80 50 49 63 92

100 56 56 68 94

125 55 55 73 89

160 56 56 72 92

200 55 55 69 92

250 54 54 69 96

315 51 51 70 93

400 55 55 71 88

500 53 52 71 92

630 53 53 76 93

800 56 55 68 93

1000 53 53 68 92

1250 54 53 68 91

1600 54 54 66 91

2000 57 57 66 90

2500 56 56 66 91

3150 54 54 66 87

4000 51 51 66 85

5000 49 48 65 85

6300 47 47 65 83

8000 43 46 65 80

10000 65 77

12500 48 48 63 75

16000 54 55 65

20000 68 68 69

1. Hand brace and 1" wood bit, cutting.

2. Hand brace and 1" wood bit, cutting.

3. Hand brace and 1" wood bit at breakthrough.

4. Electric-powered saber saw.

77
ATTACK 20M

One-third octave sound pressure levels, dB

Frequency

Band

Kz

20

25

31

40

50

63

80

100

125

160

200

250

315

400

500

630

800

1000

1250

1600

2000

2500

3150

4000

5000

6300

8000

10000

12500

16000

20000

83

84

79

80

65

68

73

85

87

87

83

86

86

86

88

89

90

89

90

90

90

90

89

89

89

89

88

83

82

76

74

66

65

66

64

56

56

62

68

61

65

63

64

59

65

68

75

72

70

68

67

71

70

69

66

69

68

62

51

50

58

72

5. Electric-powered rotary saw.

6. Electric drill with 3/4" wood bit,

78
ATTACK 2 IN

One-third octave bandwidth sound pressure levels, dB

Frequency

Band

Hz

20

. 25

31

40

50

63

80

100

125

160

200

250

315

400

500

630

800

1000

1250

1600

2000

2500

3150

4000

5000

6300

8000

10000

12500

16000

20000

69

65

61

69

72

70

73

74

82

77

72

72

78

77

83

84

82

89

90

89

90

89

88

87

87

87

88

84

83

80

78

86

84

85

80

80

77

68

70

66

64

61

59

59

65

66

64

61

63

62

62

60

59

59

57

57

57

73

7. Electric-powered rotary saw.

8. Carpenter's hand saw cutting wooden joist

79
OTHER ATTACKS

One-third octave bandwidth sound pressure levels, dB

Frequency

Band

Hz

10

20

25

31

40

513 63

BQ

100

125

160

200

250

315

400

500

630

800

1000

1250

1600

2000

2500

3150

4000

5000

6300

8000

10000

12500

16000

20000

55

54

56

54

55

57

63

68

62

70

67

73

75

73

76

78

81

80

79

80

81

81

SI

80

80

80

81

82

82

84

84

93

87

83

80

77

75

80

88

82

85

85

86

95

94

94

92

92

92

93

94

95

97

99

101

102

105

105

103

103

101

98

9. Oxyacetylene torch cutting metal grill.

10. Breaking window glass.

80
ATTACK 22A

One-third octave bandwidth sound pressure level, dB

Frequency'

Band

Hz

20

25

31

40

50

63

80

100

125

160

200

250

315

400

500

630

800

1000

1250

1600

2000

2500

3150

4000

5000

6300

8000

10000

12500

16000

20000

11

85

86

86

76

76

77

75

89

85

93

92

95

96

94

94

91

88

87

85

82

81

76

77

72

68

68

65

69

79

93

12

76

87

86

80

78

78

77

86

89

92

93

90

96

94

88

86

87

85

84

83

79

76

77

69

67

66

84

11. Twelve-pound sledgehaimner attack on brick veneer.

12. Sledgehammer attack on cinder block after penetration

of brick veneer.

81
ATTACK 22B

One-third octave bandwidth sound pressure level, dB

1 " Frequency

Band

Hz .

13 14 15

.t

20 65 64 78

25 68 74 75

31 83 82 69

40 81 76 62

50 86 75 59

75 73 60

80 75 73 52

_L100W W 90 91 62

125 82 81 58

_L1 fiO \J W 90 88 66

200 89 94 71

250 82 93 72

315 89 93 69

400 92 95 71

500 92 98 72

o 92 99 71/ J- 800 93 100 73

^ 000 91 99 74

1250 90 96 75

J. w w 85 93 77

2000 87 89 80

9 son 86 86 81

3150 88 89 82

4000 85 89 82

5000 88 93 81

6300 90 101 81

8000 83 94 82

10000 78 90 81

12500 78 86 79

. 16000 82 77

20000 84 84 83

13. Rotohammer with 1-1/2" chisel attacking brick veneer.

14. Rotohammer with chisel attacking cinder block after penetration

of brick veneer.

15. Oxyacetylene torch cutting reinforcing bar.

82
ATTACK 27T

One-third octave bandwidth sound pressure levels, dB

Frequency

Band

Hz

16

20 41. 93

25 49 96

J i. 70/ w 97

61 96

so 47H / 9R

47 QD

U J

±.\j\j 1 on 7S

fi7 X1 fiO vj W

71/ J. 1 m

^900WW / X QQ

71/ J. 76 70

400 77/ / xvjx soow w 71 QQ

630 73 9S

800 11 98

1000 71 98

1250 74 97

1600 75 97

2000 11 97

2500 82 96

3150 82 95

4000 82 94

5000 79 93

6300 74 91

8000 73 88

10000 71 86

12500 69 82

16000 65

20000 75

17

16. Bolt cutter clipping expanded metal.

17. Sledgehammer attacking metal-clad door,

83
ATTACK 23B

One-third octave bandwidth sound pressure level, dB

, „ ———

Frequency

Band

Hz

1 Q zu

....

20 88 78 70

25 86 76 72

31 82 79 71

40 76 80 71

50 80 92 75

63 75 79 71

80 77 79 66

100 97 93 82

125 84 92 74 : I 160 88 101 79

200 92 102 82

250 91 97 79

315 88 98 82

400 91 101 80

500 92 103 83

630 94 100 87

800 95 100 84

1000 93 97 84

1250 93 98 85

1600 89 94 91

2000 86 96 85

2500 81 96 84

3150 79 97 89

4000 86 93 92

5000 95 90 91

6300 97 89 86

8000 88 88 91

10000 94 86 88

12500 98 85 83

16000 91 83

20000 93 94 93

18. Rotohammer with 1" drill attacking concrete.

19. Spalling concrete with 12-pound sledgehammer.

20. Gasoline-powered abrasive wheel cutoff saw.

84
FORM NBS-114A (1-71) U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 73-223

2. Gov't Accession No.3. Recipient's Accession No.

4. TITLE AND SUBTITLE

PENETRATION TESTS ON J-SIIDS BARRIERS

5. Publication Date June 4, 1973

6. Performing Organization Code

650.01

7. AUTHOR(S) R. Moore 8. Performing Organization

NBSIR 73-223

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No. Project 6509419

11. Contract/Grant No. lACRO DNA EO 72-201

and 73-406

12. Sponsoring Organization Name and Address

Defense Nuclear Agency (DNA)

Washington, D. C. 20305

13. Type of Report & Period Covered Interim Report

Lor renoQ j/±j—±d//j

14. Sponsoring Agency Code

DNA

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here.) A series of penetration tests were made on three simulated ams rooms which

incorporated a variety of structural barriers which were intended to be representative

of the broad range of construction likely to be encountered in existing arms rooms.

The observed penetration times varied from 1.3 minutes for a double-planked wooden

wall, 11.31 minutes for an eight-inch thick, reinforced concrete wall and up to 18.27

minutes for a GSA Class 6 vault door. All penetrations were made with portable readily

available tooling and produced acoustical or vibrational or both types of disturbances

which are readily detectable.

The test results provide a basis for estimating the time in which response to an intrusion alarm must occur in order to adequately safeguard an arms room, a computer room or any other sensitive area.

17. KEY WORDS (Alphabetical order, separated by semicolons)

Barrier penetration; Intrusion resistance; physical security.

18. AVAILABILITY STATEMENT

rX| UNLIMITED.

I I FOR OFFICIAL DISTRIBUTION. DO NOT RELEASE

TO NTIS.

19. SECURITY CLASS

(THIS REPORT)

UNCL ASSIFIED

20. SECURITY CLASS

(THIS PAGE)

21. NO. OF PAGES

22. Price

UNCLASSIFIED

USCOMM-DC 66244.P71