TA2018001 BOS REPORT_PART8.PDF

used as a standard. Billboard-to-viewer distances are proposed to be as provided in table 2
above.
Table 3 summarizes the recommended maximum billboard luminance values based on tables 1
j^r»d
, Thftsft r.an be adopted directly into an ordinance or set of guidelines.
The limitations of TM-11-00 were established through research conducted by Lighting Sciences
Inc. under a contract from the Lighting Research Office of EPRI (Electrical Producers'
Research Institute). The basis of TM-11-00 was subsequently provided to lESNA to form the
publication. Field use of the values for various forms of outdoor fighting confirm that the
values are realistic and prevent undue annoyance to a majority of viewers, and thus appear to
have formed a satisfactory basis for specifying such fighting limits.
The procedures outlined in this section of this report, method 2, specifications based on light
trespass, are recommended by Lighting Sciences Inc. for evaluation and possible subsequent
adoption by OAAA.
A3.7 Enforcement
After a billboard is installed, there wiU be cases where it is desired to evaluate the billboard
luminance to ensure that it does not exceed the specified value. This procedure is extremely
simple and requires only a footcandle meter.
Tliehillboard-luminance specification is based on ensuring-that a-eertain footcandle level— -
created by the billboard is not exceeded at a chosen distance. Thus all that is needed to check
compliance is the measurement of the footcandles level at that distance with the billboard on
and off. The footcandle meter would be held at a height of 5 ft. (which is approximately eye
height) and aimed towards the billboard, from a distance as selected from table 2. If the
difference in illuminance between the billboard-on and billboard-off conditions is 0.3 fc, then
the billboard luminance is in compliance. When conducting this check, the meter should be at a
location perpendicular to the billboard center (as seen in plan view) as this angle has the highest
lumioance.
This check should include the measurement of an aU white image displayed by the billboard to
evaluate the worst case condition.
A4. Summary of Proposed Method
Specification based on the fight trespass limits adopted by lESNA in publication TM-11-00
appears to provide a manageable and technically viable technique.
13

It is proposed to use the lESNA recommended limits for environmental lighting zone E2, low
level electric lighting, as a standard. This limits the maximum illuminance produced by the
billboard and measured at tlie eye of a viewer to 0.3 footcandles over ambient. It is further
proposed that the viewer be positioned from the billboard at ground level and facing in a
Himctinn peipendicnlarto the billboard. The distance will be dependent upon the billboard size.
Under these conditions, to meet the 0.3 fc limitations, the maximum allowable billboard average
luminance will be as given in table 3 for various standard billboard sizes. The percentage
dimmer setting, expressed as a percentage of the billboard maximum luminance, can be
calculated from the table 3 luminance value, based on the maximum luminance of a billboard
being 7000 cd/sq.m. or some other known value.
Because these values have been derived from lESNA publication TM-11-00, which in turn is
based on an extensive human factors research project, adoption of such values should satisfy the
requirement that most persons will not find these billboard luminances to be objectionable.
SECTION B - 
BILLBOARD LUMINANCE : 
DIGITAL VERSUS CONVENTIONAL
The foregoing has provided recommendations for the average luminance limits for digital
billboards. It is of interest to compare these to frie luminance levels found with conventional
billboards. Such billboards are most commonly lighted using liiminaires designed for this
specific purpose, manufactured by the Holophane Company. Most installations consist of a
series of fixtures that use 400 watt Metal-Halide lampSi- Typically a I4 x 48 
large billboard-is
lighted by four such fixtures moimted along the bottom edge of the billboard. Some billboards,
employ a lighting system using only three bottom moimted luminaires. Other designs may use
top mounted lighting in various configurations. An optical refractor or lens is used on each
luminaire to direct light onto the billboard, which increases the billboard luminance.
The luminance of conventional billboards has been addressed in a study by the Lighting
Research Center of Rensselaer Polytechnic Institute that was sponsored by frie New York State
Department of Transportation. A technical memorandum has been developed titled "Evaluation
ofBillboard Luminances" dated March 31, 2008. This memorandum states the following:
"... it is probably reasonable to expect that the luminance of a conventional billboard would not
be likely to exceed about 280 cd/sq.nu during the nighttime (assuming typical lighting practice
as represented by the lESNA and industry recommendations, and by the lighting systems used
on the billboards that were measured in the field)..."
The report indicates that the value of 280 cd/sq.m. (nits) is consistent with clean billboard
lighting systems using new lamps. This is also the condition used for testing the digital
billboard at Lighting Sciences' laboratories as referenced above.
TT

It is thus anticipated that digital billboards operated in accordance with the recommendations
developed above, (300 to 342 nits, depending on size), will be brighter, but only slightly
brighter, than the maximum luminance of conventional billboards.
SECTION C 
~ SKY GLOW
C1 
Introduction
A hirther factor, "sky glow," has been addressed in relation to both conventional and digital
billboards.
Sky glow is caused by light at night entering the atmosphere and being scattered by airborne
particulates. Sky glow may result from the use of lighting fixtures that emit light above a
horizontal plane so that it enters the atmosphere directly. The effect also is caused by light
reflecting from lighted objects, such as a road surface, a building or a billboard.
It is highly desirable to reduce sky glow in order to preserve dark skies. This is an
environmental concern, as well as a significant factor influencing the ability of astronomers to
study the night sky.
The amount of light entering the atmosphere from a variety of lighting installations has been
evaluated.- -Measured in "sky lumenSj" the results allow a-comparison to be made-of different —
lighting systems relative to sky glow. Specifically calculations have been made to compare the
sky lumens produced by a typical billboard lighting system to the sky lumens caused by roadway
and parking lot lighting. Extensive work was conducted for conventional billboards, then later
work compared newer digital billboards to the conventional billboards.
Various scenarios were used for the roadway lighting, combining residential and major highway
lighting in a typical neighborhood. Areas were considered that consist only of roadway lighting,
as well as areas that contain both roadway and parking lot lighting.
C2.1 Conventional Billboards
A 14 X 48 ft. billboard was evaluated using both three and four bottom mounted Holophane
"Panel Yue" fixtures. Each was equipped with a 400 watt metal halide lamp rated at 40,000
lumens. Photometric test data were obtained from the manufacturer and computerized
calculations were performed.
15

All calculations were based on a 0.70 Light Loss Factor, or Maintenance Factor, to account for
the reduction of light output as the lamp ages and as the fixture collects dirt.
For both the three and four fixture lighting systems, the following quantities were calculated:
Total uplight lumens emitted by the group of fixtures
Total lumens intercepted by the billboai'd
Total lumens intercepted by the billboard underboard
Total lumens emitted upwards by fixture that do not strike the billboard or underboard.
(Direct sky lumens)
Total lumens reflected upwards by the billboard
Total lumens reflected upwards by the underboard
Total lumens reflected upwards. (Indirect sky lumens)
The manufacturer's data were used directly; no additional shielding was assumed for the lighting
fixtures.
Results obtained for the three and four fixture systems in terms of total sky lumens are as
follows:
3 fixture system: 23,415 1ms
4 
fixture system: 31,535 1ms
These values-will be affected by the reflectance of-the-billboard face material, which is
dependent on the lightness/darkness of the material. An average value of 25% was used, derived
from laboratory measurements of sample billboard face materials. A reflectance value of 2.5%
was used for the underboard.
No account is taken in these calculations of the angular direction of the uplight lumens as they
enter the atmosphere, which is likely to have some influence on the degree of sky glow that is
produced.
C2.2 Roadway Lighting
For this study, billboard lighting was compared to roadway lighting. "While it is recognized that
there axe many sources of nighttime light other than roadway lighting, this form of lighting
usually constitutes a major source of uplight lumens.
LSI has produced roadway lighting designs for three different roadway types and has computed
resultant uplight lumens, as follows:
16

Local roadway. Illuminating Engineering Society of Nortli America (lESNA) specification is
0.7 footcandles average maintained lighting level, with a 6; 1 average to minimum
uniformity, (i.e. The minimum footcandles at any point wiU not be less than one sixth of the
average.)
Collector roadway. lESNA specification is 0.9 fc maintained, 4:1 uniformity.
Majorroadway. lESNA specification is 1.3 fc maintained, 3:1 uniformity.
hi all three cases, "medium pedestrian conflict" per lESNA was assumed.
A Light Loss Factor or Maintenance Factor of 0.70 was used, so as to be equivalent to the same
factor used for the billboard calculations.
For each roadway, lighting system design has been conduced using a flat glass "fiill cut off'
fixture, and the older style "cobra-head semicutoff' fixture with glass bowl lens. The full cut off
fixture allows no light to escape above the horizontal, while the semicutoff fixture emits a few
percent of its total lumens above the horizontal.
Most existing roadways, particularly where the lighting was installed 15 or more years ago, will
use the glass bowl lens. Because of a desire to control sky glow, many agencies have now
switched to full cut-off optics. In any urban area, both types of fixtures are likely to be present.
By analyzing roadway lighting with each of these fixture types, a realistic range of possibilities is
examined.
For all designs, various pole heights were investigated. Each design was optimized to acquire
the maYiirmm pole Spacing that can be used while meeting the lESNA lighting specifications.
Thus the design procedures were similar to those used by typical roadway lighting designers.
For each lighting system, the following were calculated, all on the basis of a single mile of
roadway:
Total lumens falling on the roadway
Total lumens falling on the ground outside of the roadway
Total lumens reflected upwards from tlie roadway
Total Imnens reflected upwards from the ground outside the roadway
Total lumens emitted upwards dii'ectly from the fixtures. (This quantity is zero for the cutoff
fixture.)
Typical known reflectance values were used for the road surface and areas outside the roadway.
17

Results of the computation, given in sky lumens per mile are as follows:
Local roadway, tiill cutoff fixture: 
25,837 sky lumens per mile
Local roadway, semicutoff fixture: 
38,079 sl<y lumens per mile
^Collectorj:oadway,,full.cutoffiixture: 
4.7,652..sky lumens_pei:_mile
Collector roadway, semicutoff fixlure: 
64,071 sky lumens per mile
Major roadway, M 
cutoff fixture: 
153,355 sky lumens per mile
Major roadway, semicutoff fixture: 
259,910 sky lumens per mile
C2.3 Comparison of Conventional Billboards and Roadway Lighting
Based on the above values, the sky lumens produced by one billboard using a three fixture
lighting system are approximately equal to the sky lumens produced by:
0.91 miles of local roadway with full cutoff fixtures
or 
0.49 miles of collector roadway with full cutoff fixtures
or 
0.15 miles of major roadway with full cutoff fixtures
or 
0.61 miles of local roadway with semicutoff fixtures
or 
0.37 miles of collector roadway with semicutoff fixtures,
or 
0.09 miles of major roadway with semicutoff fixtures
The sky lumens produced by a four fixture billboard lighting system are roughly equal to the sky
Imnens produced by:
1.22 miles of local roadway with fiill cutoff fixtures
or 
0.66 miles of collector roadway with full cutoff fixtures
or 
0.21 miles of major roadway with full cutoff fixtures
or 
0.83 miles of local roadway with semicutoff fixtures
or 
0.49 miles ofcoUector roadway with semicutoff fixtures,
or 
0.12 miles of major roadway with semicutoff fixtures
As another way of comparing the data, the total roadway lighting per square mile of an urban
area can be computed and compared to billboard lighting. An example city square mile has been
checked (in Denver, CO). For a typical urban built-up area, the following roadway lengths were
present in the selected 1 sq. mile:
Total length of local roadways: 21 miles
Total length of collector roadways: 1 mile
Total length of major roadways: 1 mile
18

The total sky lumens assuming all roadways are lighted for this square mile have been calculated
and are:
For all roadways hghted by hill cutoff fixtures: 743,584 lumens
For-alLroadways-lighted-by. semicutoff.fixtiires:.„l.,123,fi4D lumens
If a single billboard is situated in this example square mile, the percentage of total sky lumens
created by the billboard lighting is as follows:
Billboard sky lumens as % 
of total, for 3 fixture system, when roadways are lighted with full
cutoff fixtures: 3.1%
Billboard sky lumens as % 
of total, for 4 fixture system, when roadways are lighted with full
cutoff fixtures: 4.2%
Billboard sky lumens as % 
of total, for 3 fixture system, when roadways are lighting with
semicutoff fixtures: 2.1%
Billboard sky lumens as % 
of total, for 4 fixture system, when roadways are fighting with
semicutoff fixtures: 2.8%
Other assumptions for the density of roadway fighting and number of billboards can be similarly
determined. For example, if the roadway lighting is as above, but the density of billboards is
halved, the percentage sky glow from the billboards with be halved.
In certain urban areas, the roadway lighting usage may be greater than in the selected example
area: There may be other-sources of sky glow such as-floodlighting for buildings and sports
facilities. In such conditions, the percentage contribution of a given amount of billboard fighting
to the overall sky glow wiU be reduced. In yet other areas, roadway lighting may be less than
that illustrated above, and the proportion of sky glow produced by the billboard will be higher.
Further efforts under an extended reseai'ch program could analyze large urban areas and survey
fighting usage by types.
C2.4 Parking and Roadway Lighting
As another example scenario, calculations have been made for a 1 square mile area consisting of
both roadway lifting and parking lot fighting. In this example, a parking lot size of one quarter
mile square has been included. The total length of local roadways has been reduced to 16 miles.
The parking lot is assumed to be lighted to an average level of 1.5 footcandles.
Because tlie parkmg lot is lighted to a higher level tlian tlie roadway it replaces, and because a
larger area is bemg lighting, the total sky lumens are increased versus the earlier example that
assumes the presence of roadways only.
19

The modified values of total sky lumens are:
For all roadways and parking ai'eas lighted by full cutoff fixtures: 836,687 lumens
For all roadways and parking area lighted by semicutoff fixtures: 1,273,028 lumens
If a single billboard situated in this example square mile, the percentage of total sky lumens
created by the billboard lighting is as follows:
Billboard sky lumens as % 
of total, for 3 fixture system, when roadways and parking areas are
lighted with full cutoff fixtures: 2.8%
Billboard sky lumens as % 
of total, for 4 
fixture system, when roadways and parking areas are
lighted with fiill cutoff fixtures: 3.8%
Billboard sky lumens as % 
of total, for 3 fixture system, when roadways and parking areas are
lighting with semicutoff fixtures: 1.8%
Billboard sky lumens as % 
of total, for 4 
fixture system, when roadways and parking areas are
lighting with semicutoff fixtures: 2.5%
It should be noted that in this analysis, all lumens reflected fi-om surfaces or emitted upwards
directly from the fixtures are assumed to enter the sky. This is probably true for most billboard
lighting systems. For roadway and parking lot lighting, however, reflected light may be blocked
by objects such as buildings or trees. If this blockage is 50%, for example, the above percentage
contribution of billboard lighting to sky lumens will be doubled. Nonetheless, even assuming a
scenario where all roadway and parking lot lighting sources are fully-shielded fixtures, the sky
glow caused by billboards is a small percentage of the overall sky-glow, under the conditions —
evaluated.
C3 
Digital Billboards and Sky Glow
The scenario to be evaluated for digital billboards in relation to sky lumens is completely
different from conventional billboards: There is no reflecting billboard surface and no exterior
luminaires, as the digital pixels themselves are the li^t sources. Some light from the pixels is
emitted in directions below the horizontal where it provides the advertising message to viewers
and some light is emitted above the horizontal where it enters the atmosphere (unless blocked by
trees and structures). 
•
The photometric test data for the digital billboard sample tested at Lighting Sciences'
laboratories has been examined, and calculations have been performed to determine the sky
lumens tliat will be generated for a typical 14 x 48 ft. digital billboard.
It is significant to note that the digital billboard as tested is designed to direct the majority of its
light below the horizontal, in tlie dfrection of the viewer location. This is achieved by the use of
20

horizonal louver blades that ai'e angled downwards and tliat ivn between adjacent rows of pixels.
This is illustrated in figure 1; in this figure, the lengths of the arrows represent the actual
intensities of the light rays in the various directions as documented in the laboratory photometric
test report. For example, fight intensity emitted 20 degrees below the horizontal is more than
dmiblft the intensity emitted 20 degrees above the horizontal. This has tlie obvious effect_pf
reducing sky lumens versus that which would be produced if fight above and below the
horizontal were equal.
Elimination of bottom mounted exterior luminaires commonly used for conventional billboards
play a very significant role in the reduction of sky glow. For the example scenario detailed
earlier in this report, where a four luminaire bottom mounted system produces 31,535 sky
lumens, roughly 90% of those lumens are emitted into the sky directly firom the fixtures.
For the digital billboard calculations, it was assumed that no dimming of the fight output occurs
due to age, as the computerized controls can be set to overcome any LED light output
degradation with time. A Light Loss Factor of 0.90 was assumed to account for a possible 10%
loss due to the accumulation of dust and dirt.
For the conventional billboard discussed above, a 25% average reflectance was used in the given
example. A similar "message" was assumed for the digital billboard calculations, i.e., a
billboard luminance was assumed that would be created by an array of colors equivalent to that
used for the conventional billboard analysis, rather than an all white display. It was further
assumed that a 14 x 48 ft. bfilboard woifid be operated at 4.3% of full output at night, as
recommended in table 4 above. For these-example conditions, the amount of fight directly-
emitted into the atmosphere by the digital billboard is 2260 lumens. This compares to the value
of 31,535 sky lumens for the example conventional billboard lighted by four bottom mounted
luminaires, and is 8% of that amount.
Digital billboards can be seen to offer a major opportunity to reduce sky glow if they are
replacing conventional billboards that employ a bottom mounted lighting system. This is a result
of the elimination of the external luminaires and the direct sky lumens they produce, ^d also
because of the design of digital billboards whereby less light from the billboard face is directed
upward versus downward.
Ian Lewin Ph.D., FIES, L.C.
October 1,2008
21

Effect of Horizontal Louver Blades
Billboard
Length of Arrows Represent Light Intensity
Uplight is Partially Shielded
Figure 1
22

Appendix A
»
 
Lighting Units and-Xerms
Several terms are usefiil in describing the light characteristics of digital billboards. See figure
Al.
Billboard Luminance, L
or Brightness
(Candelas per sq. meter,
or nits)
Intensity, 1
or Candlepower
(in Candelas)
Billboard Area, S .. . ..
Billboard produces
Illuminance
at viewer's eye
(In Footcandles)
Distance, D
Figure A1
Candlepower. This is the intensity, I, of light produced by the billboard in a particular direction,
and it is measured in "candelas." For example, a billboard of a certain size will emit a certain
intensity of light in a du'ection perpendicular to its face. The intensities emitted in other
directions will be less than that in the perpendicular dhection. If the billboard displays a white
image, this intensity will be higlier tlian if tlie billboard face is any other color.
Candlepower does not change significantly with distance, providing the atmosphere is clear; the
intensity continues as the light rays move in a straight line until they sti-ike a surface.
23

Luminance, L, often called "brightness," relates to the overall appearance of the billboard. It is
the caiidlepower emitted per unit area, and is expressed in units of "candelas per square meter,"
or cd/sq.m. Say a billboai-d tliat has an area of 2 square meters produces 400 candelas when
viewed from a direction perpendicular to its face, then its luminance is 400/2, equal to 200
nH/sq.m. The term "nit" is also used. Such a billboards is said to have a brightness of 200 nits.
The formula relating the billboard size, luminance (or brightness) and the candlepower it projects
is;
Candlepower (in candelas) = Luminance (in candelas/sq.m. or nits) x billboard area (in square
meters)
or 
I = L X S 
A1.
(L is in nits, S is in sq.m.)
Illuminance, E. This is a measure of the amount of light that is intercepted by an object that is
illuminated by the billboard. Illuminance is measured in "footcandles," and is dependent on the
distance fi"om the billboard, as weU as the candlepower the billboard produces. If a viewer is
looking at the billboards, the illuminance at the viewer's eye, Ey, can be found using the "Inverse
Square Law," which states
^
 ^ Candlepower (in candelas)
niummance (m footcandles)= 
7——-—
I
 I 
Distance (m feet)
or 
E 
A2.
The value of I from equation 1 can be substituted into equation 2 to give
E
 
A3.
Equation 3 is very useful because it relates billboai'd size (S), billboard luminance (or brightness)
(L), and gives the footcandles (Ey) that will be produced by tiie billboards at a distance, D feet. It
can be rewritten:
24

A4.
B-is^nnits^-Ev-isin-footcandlesr
D 
is in feet, S is in sq. meters
Otherwise, if the area of the billboard, S, is in square feet, the equation becomes
10.76 D' 
E,.
L
A
 =
5.
L is in nits, Ey is in footcandles,
D is in feet, S is in sq. feet
The illuminance, E, can be measured easily with a relatively inexpensive footcandle meter at a
measured distance D feet horn the billboard. Figure A2. The area of the billboard, S,
presumably is known. Inserting these values of E, D and S into equation 5 allows the luminance,
L in nits, to be calculated.
Eye
Footcandle Meter
Figure A2. Measuring Illuminance (in Footcandles) at the Viewer's Eye Location
Eye Location
TI
Nit Gun
Figure A3. Measuring Billboard Luminance (in Nits) Using a Nit Gun Aimed at Billboard
25

L, the billboard luminance, can also be measured with a "nit gun", which is a luminance meter
that can be pointed at the billboard. Figure A3. However such devices are more expensive and
less readily available than a footcandle meter.
Rftcausp. nf the simple relationship as given in equation A5. billboard luminance specifications
can be written in terms of footcandle limitations at a certain distance. For compliance checking,
if the footcandle value produced by the billboard and measured at a prescribed distance is at or
below a specified level, then it will be known that the billboard luminance meets the desired
limitation.
26

Appendix B
Description of the Lighting Environmental Zone (from lESNA publication TM-11-00)
El. Areas with intrinsically dark landscapes. Examples are national parks, areas of outstanding
natural beauty, or residential areas where inhabitants have expressed a strong desire for shict
limitation of light trespass.
E2. Areas of low ambient brightness. These may be suburban and rural residential areas.
Roadways may be lighted to typical residential standards.
E3. Areas of medium ambient brightness. These will gener^ly be urban residential areas.
Roadway lighting will normally be to traffic route standards.
E4. Areas of high ambient brightness. Normally this category will include dense urban areas
with mixed residential and commercial use with a high level of nighttime activity.
Note: The above descriptions are being considered for revision by lESNA at the time of writing
this report. The categories are not changed, but the descriptions are more extensive for clarity.
27

EXHIBITS

[DIGITAL BILLBOARDS TODAY]
[CHANGING THE DELIVERY OF
INFORMATION]
Billboards are the oldest mass medium. The first
standardized posters appeared in the 19th century
and, not surprisingly, the medium has adapted
over time. What \A/as once a poster on the side of
a building became a freestanding, purpose-built
billboard. Hand painting on a sign became printed
paper pasted on the board. Paper and paste is
giving way to computer-generated images on
plastic substrates. Today, the next generation of
billboards is digital.
These dynamic tools for advertisers and
communities represent a small fraction of the total
number of billboards in the United States. There
are an estimated 400,000 billboards faces in the
United States; about 5,200 of those are digital,
or one percent. Yet the communities which have
digital billboards have come to rely on them.
as varied as the places they serve.
As with any new technology, there are questions
about how best to incorporate digital billboards
Into the existing body of regulations and aesthetic
fabric of an area. The following pages give a broad
overview of how communities have answered
those questions and why virtually every state
and hundreds of municipalities welcome digital
billboards.
[REGULATORY FRAMEWORK]
Ail billboards are heavily regulated. The federal
government, state government, and counties,
cities, and towns regulate outdoor advertising.
To keep pace with technology, the federal
government has said roadside billboards (off-
premise signs) could use "changeable-message"
technologies as long as these signs don't scroll or
flash.
The uses for this exciting technology are
as varied as the places they serve.
Small business owners turn to them as an
affordable way to reach a large number of
customers with a dynamic message. Public safety
organizations rely on them to help bring fugitives
to justice and provide emergency information. The
news media use them to give up to the minute
news and information to an increasingly mobile
audience. The uses for this excifng technology are
DUNKIH
DONIIT9
On September 25, 2007, the Federal Highway
Administration (FHWA) issued a guidance memo to
states:
"Proposed laws, regulations, and procedures
that would allow permitting CEVMS (changeable
electronic variable message signs, the official name
for digital billboards) subject to acceptable criteria
... do not violate a prohibition against 'intermittent'
or 'flashing' or 'moving' lights as those terms are
used in the various FSAs (federal-state agreements)
that have been entered into during the 1960s and
1970s."
The 2007 memo gave states the green light to
approve digital billboards, as long as there were
appropriate regulatory controls in place. The
memo went on to list suggested areas of control,
including lighting, display time, and transition time
(the amount of time it takes for one message to
change to another message).
Industry practices conform to federal guidance.
FHWA recommends an eight second display time, a
oaaa

suggestion mirrored by industry standards. Federal
guidelines say digital billboards should "adjust
brightness in response to changes in surrounding
light levels so that the signs are not unreasonably
bright." Digital billboards are equipped with
sensors to make sure the billboards are only as
bright as necessary to be legible. Messages change
instantaneously, avoiding transition effects.
States and localities have added regulations for the
size and spacing of digital billboards.
The OAAA Code of Industry Principles includes
clauses against animation and excessive lighting.
[TRAFFIC SAFETY]
Industry practices conform to federal
guidance.
Safety can be among the most contentious
questions raised about digital billboards. The
debate is puzzling, however, as research on
modern digital billboards has found them to be
"safety neutral" and unrelated to traffic accidents.
Specifically, studies
Foundation
for Outdoor
Advertising
Research and
Education (FOARE)
have considered
digital billboards
and driver
distraction from
two different
angles.
issioned by the
i
HUTCHINSONSEPTIOjIB
billboards and other objects in their field of vision.
The study found the typical glance toward a digital
billboard was less than one second.
This finding is important, because a separate study
released in 2006 by VTTI for the National Highway
Traffic Safety Administration (NHTSA) identified
a two second threshold for increased risk due
to distraction: "Glances totaling more than two
seconds for any purpose increase near-crash/crash
risk by at least two times that of normal, baseline
driving." The typical glance toward a digital
billboard is well under the threshold.
"I ... have no Indication that digital billboards pose any
safety threat to the traveling public. With the number of
digital signs that are currently in E! Paso, both of the busi
ness and billboard type, and the long time In which they
have been present In our city, any safety Issues surely would
have surfaced by now. Those In El Paso who claim there are
safety problems with the digital billboards are ignoring the
evidence."
—Richard Wiles, El Paso County (TX) Sheriff,
in a letter to the El Paso City Council
One study was
performed by the Virginia Tech Transportation
Institute (VTTI), an academic traffic safety
research institute used by government agencies
and the private sector. Researchers analyzed the
eye glances of drivers along with driving factors
such as lane changes and speed. Randomly
selected people drove a specially equipped car
which monitored when their eyes moved toward
Accident records
indicate digital
billboards are not
a traffic safety
risk. Multiple
comprehensive
studies have been
performed by
Tantala Associates,
a consulting
engineering
firm based in
Philadelphia,
which has
performed analytical research for various levels
of government. Since 2007, researchers have
examined years of accident data for highways and
local streets in Cuyahoga County (Cleveland) OH,
Rochester, MN, Albuquerque, NM, Reading, PA,
and Richmond, VA. Each study reached the same
conclusion: there is no correlation between digital
billboards and traffic accidents.
oaaa

LAKERS
CELTICS
These analyses looked
at various view zones,
or distances, from the
digital billboards and
other factors such as
deer hits and weather
conditions (known as
"bias factors"). The
studies accounted for
differences between
younger and older
drivers and driving
during the day and at night. No matter how the
accident data were analyzed, the conclusion was
the same: digital billboards are safe.
Several states have also performed their own
studies related to digital billboards, looking
at accident data near digital billboards.
Transportation officials in South Carolina, Virginia,
and West Virginia reported digital billboards have
not caused traffic safety problems. Local officials
have also reviewed accident records.
Furthermore, the US Department of
Transportation's Federal Highway Administration
(FHWA) research has concluded that drivers are
"generally more likely to gaze at CEVMs than at
standard billboards." But, the average glance
durations were well within the safe limit of two
seconds already defined by the National Highway
Traffic Safety Administration (NHTSA). In short,
the researchers said, "the results did not provide
evidence indicating that CEVMs, as deployed and
tested in the two selected cities, were associated
with unacceptably long glances away from the
road", adding that "the demands of the driving
task tend to affect the driver's self-regulation of
gaze behavior."
[PUBLICOPIIMION]
In 2008 and 2009, Arbitron sought to answer a
relatively simple question: what does the public
think about digital billboards? Arbitron researchers
found people are aware of and positively Inclined
toward this new technology.
The Arbitron studies focused on two metro areas
(Cleveland, OH, and
Los Angeles, CA),
where digital billboards
operate. Through
telephone surveys,
researchers found
"the vast majority of
commuters (more
than four out of five)
feel digital billboards
provide an important
community service."
More than seven out often people said digital
billboards help the community with emergency
information, and the majority said they were
attractive. Cleveland Councilman Joe Cimperman
described digital billboards as modern and tech-
sawy.
Among younger demographics, digital billboards
are even more popular. The Arbitron studies found
high percentages of those 18-34 consider digital
billboards attractive, while a majority agreed
digital billboards help the community by providing
emergency information. More than three quarters
of 18-34 year olds said digital billboards are a "cool
way to advertise."
[PUBLIC SERVICE]
Among the most important users of digital
billboards are law enforcement agencies. The FBI,
the National Center for Missing and Exploited
Children (NCMEC), the US Marshals Service, and
county and city sheriff and police departments use
digital billboards to help keep their communities
safe.
"Digital billboards are right in line with the whole
cityscape. They communicate that we are a city
that embraces technology. We
actually have some of the newest state-of-the-art,
cutting edge advertising,"
- Cleveland Councilman Joe Cimperman
Because digital billboards can be updated remotely
and instantaneously, they are ideal for quickly
oaaa

Bank Robbef
Bandit
OCQ
pushing emergency
information to
the public. In
2008, NCMEC
(which operates
the national
AMBER Alert
system) signed
an agreement
with the outdoor
advertising industry
to display AMBER
Alerts on digital billboards. Since then, hundreds
of abducted children were displayed on digital
billboards within minutes of the Alerts being
issued. Almost all of those children were quickly
reunited with their families.
The FBI uses digital billboards to track down
wanted fugitives and crack difficult cases. In
August, 2010, agents activated digital billboards
nationwide to identify and arrest a suspected
serial bank robber who was wanted in a dozen
states. Agents had been investigating the case
for almost two years, yet it took just nine days to
identify and arrest the bank robber after his image
was displayed on digital billboards. The FBI credits
digital billboards
with generating
the tip leading to
the man's arrest.
Typically, law
enforcement
agencies are given
access to digital
billboards for free.
AMBER Alerts
preempt paying
advertisers and the outdoor advertising industry
maintains a sophisticated computer network to
instantly notify operators in every state with digital
billboards of every new Alert at no cost to the
government. The FBI uses a similar system at no
cost to taxpayers.
To date, the FBI credits digital billboards with
directly leading to more than 52 arrests. When
local fugitives are added to that total, the number
is even higher. Law enforcement officials agree
digital billboards make communities safer.
Law enforcement officials agree digital
billboards make communities safer.
"if we have a crack at over a quarter-million
people seeing that photo every day, then we
have a very good chance at catching the
person we're after,"
-Special Agent Sean Quinn, FBI-Newark

ihe Na6'<^'^S,0uiorHei^'s Xd'^^'yEihglnifuslry
Key Points regarding the FHWA Research
• The Federal Highway Administration (FHWA) contracted the Science Applications International Corporation
(SAiC) to study the effects of digital billboards on driver attention and distraction in 2007.
• This study was aimed at determining if digital billboards posed an unsafe driver distraction and was based on
how long drivers took their eyes off the road when in the presence of digital billboards.
• FHWA emphasized that the study employed highly accurate state of the art research methodology and eye
tracking equipment, which ensures a high level of confidence in the eventual findings.
• The study was completed in early 2010, and a draft report was subjected to peer review in 2012.
• On December 30, 2013, FHWA released its final report
The FHWA conducted its research on digital billboards based on an eye-glance analysis in two test markets:
Reading, PA, and Richmond, VA.
In both cities, digital billboards were located on freeways and local arterials.
Results from the FHWA study Indicate the following:
1. The presence of digital billboards does not appear to be related to a decrease in looking toward the
road ahead, which is consistent with earlier industry sponsored field research studies fVTTh.
2. The longest fixation to a digital billboard was 1.34 seconds, and to a standard billboard it was 1.28
seconds, both of which are well below the accepted standard.^
3. When comparing the'gaze at a CEVMS versus a standard billboard, the drivers In this studv were
more likelv to gaze at CEVIVIS than at standard billboards.
4. The researchers were careful to note the FHWA studv adds to the knowledge base of digital billboard
safety, but does not "present definitive answers" to the questions investigated.
Bottom line:
Digital billboard glances are well within federal safety standards
concerning driver distraction.
The full report is available on the FHWA website
httD://www.fhwa.dot.gov/real estate/practitioners/oac/
THEiHILL
DOT study finds digital billboards
don't distract drivers
fiK 
ta
OriveitarenslAsnclMby
esns'OssisngMtlOMf accoren^isaiiuOycGMucieflDyM
Oepanwnl or Tran^ortyjon
Ttiesiudy onct)a-asreiesMOt,;mfrayangrwa;MnHMrnoiifM) louwnalarTi«.-am
no: anr mere :*eiy !o be Mracred try 
D«9o»ils mar> t;Kan*rr
1 According to the National Highway Traffic Safety Administration (NHTSA), safety concerns arise when a driver's eyes are diverted from the
roadway by glances that continue for more than 2.0 seconds.

EXHIBIT 10

Recommended
Brightness Levels
for On-Premise
Electronic
Message Centers
(EMCs)
...
International
Sign Association
A Compilation Summary with Extracts from Industry Reports ® 
December 20 
I O

Table of Contents
NTRODUCnON
SUMMARY
RECOMMENDED
LANGUAGE
SIX STEPS:
EMC BR GHTNESS LEVELS
International
Sign Association
ISA • International Sign Association • A Summary Report on EMC Brightness Levels

Introduction
Electronic Message Centers (EMC's)
One of chc more interesting types of signage that is becoming increasingly popular is on-prcmlse electronic message centers, or EMO. 
You may have heard
EMCs being referred to as changeable message displays or digital signs.
EMCs are nar digital billboards, which advertise a good or service that is located away from where the sign is located. Rather, EMCs are digital signs that are
located on thepremises of the business, and that advertise goods and services that are provided at the location.
Digixal biUboardJoff-pmnise sign adrcrxising an auwmobik bitsiticxs away fiom where the
sim is located
Elecn-onic Message Cenur (EMQIon-premlsc sign adveysishigan automobile biuiaess shas
is located at the pLue of business
There is often confusion regarding on and off-premise digital signs. However, EMCs and digital billboards have very distinct capabilities and purposes, each
targets a specific audience and each has traditionally been treated under separate legal and r^ulatory r^?mes. For the purposes of this publication, ive are focusing
solely and exclusively on EMCs.
EMO that are too bright can be offensive and ineffective. EMC brightness is an issue where sign users, the sign industry, and the planning community have
a common goal: ensuring that EMCs are appropriately legible. We know the messages that these signs convey can be rendered unanracrive and perhaps even
unreadable if they arc programmed too bright.
That's why many sign companies recommend to their customers that in order for these signs to be most effective, their brightness be set at such a level to be
visible, readable and conspicuous.
ISA • International Sign Association 
» A Summary Report on EMC Brightness Levels

In 2008, the Incemarional Sign Association (ISA) retained Dr. Ian Lewin ofLighting Sciences to help the industry develop scientilically-researchcd, undcmandable
recommendations for EMC brightness. Dr. Lewin is a past chair of the Illuminating Engineering Society ofNorth America (lES), and is gready respected within
the lighung field. His work for ISA was conducted with the input of experts within the sign industry. Dr. Lewins full report can be found at www.signs.org.
As a resuh of this research, the recommended brightness level fr on premise EMCs is 0.3 foot candles above ambient light conditions when measured at an appropriate
distance. This is a lighting level that works in theory and in practice.
The research and the recommendarions contained in this report pertain only to EMO, 
not traditionally internally illuminated signs, such as these channel
letter and neon signs below. EMC 
s use a different lighting technology than most of these types ofsigns, and as such die scientific approach differs.
LmENS-NjHIHGS
mattress
You can rest assured that the information contained in this publication is relevant, appropriate and workable for determining EMC brightness levels.
We have provided she short steps to help guide the process and recommended statutory language. Ifyou need further assistance, feel free to contaa ISA at (703)
836-4012 to answer any of your EMC brightness questions.
EMCs and distal billboards have very distinct
capabilities and purposes, each targets a specific
audience and each has traditionally been treated
under separate legal and regulatory re^mes.
ISA • International Sign Association • A Summary Report on EMC Brightness Levels

Summary
ISA Electronic Message Display Brightness Recommendations
This summary has been developed to assist stakeholders concerned with development of brightness standards for large-format,
electronic displays used for on-premise sign applications. This summary comprises:
1) an overview of the importance ofemuring appropriate brightness,
2) technology utilized to ensure appropriate brightjiess,
3) recommended brightness standards, and
4) brightness measurement methodology.
1. Overview of the importance of ensuring appropriate
brightness.
Electronic dispiays that are too bright can be offensive and ineffective.
There are significant advantages to ensuring than an electronic display is
not overly bright. These advantages indude:
» G)nscrvauon of energy
»
 Increased life expectancy of the electronic display components
» Building goodwill with the community
y> 
Ensuring the legibility of the display
It is in the best interest of all stakeholders to ensure diat electronic displays
are sufficiendy bright to ensure dear lability, while at the same time avoiding
a display that is overly bright.
2. Technology utilized to ensure appropriate brightness.
Most electronic displays are designed to produce sufGdent brightness to
ensure dear legibility during daylight hours. Howevetj daytime brightness
setting are usually inappropriate for ni^ttime viewing. The following general
methods are used to dim an dectronic display for appropriate nighttime
viewing:
1. Manual Dimming. Using this method, the sign operator dims the
display in response to changing ambient light condidons.
2. Scheduled Dimming. Sunset-sunrise tables allow an dectronic display
to be programmed to dim at the same time that the sun sets and
rises. This method is generally acceptable, but is more effecdve when
used as a backup to automadc dimming controls capability, such as
photocell technology.
3. Photocell Technology. An electronic display that utilizes photocell
technology can automatically dim as light conditions change. A
photocdl sensor alerts the display to adjust brightness accordii^ to
ambient light condidons.
Most electronic displays are desired to
produce sufficient brightness to ensure clear
le^bility during daylight hours.
However, daytime brightness settings are
usually inappropriate for nighttime viewing.
ISA » International Sign Association • A Summary Report on EMC Brightness Levels

ISA Electronic Message Display Brightness Recommendations
3. Recommended brightness standards.
ISA commissioned Dr. Ian Lewln of Lighting Sciences, Inc. to develop
brightness criteria for on-premise electronic displays. Dr. Lewin is a leading
lighting expert with over thirty years experience in the lighting industry.
Dr. Lewin recommended the development ofbrightness criteria based on the
Illuminating Engineering Society's (lES) well-established standards pertaining
to light trespass, IBS Publication TM-II-OO. The theory of light trespass is
based on the concept of determining the amount of Hght that can spill over
(or "trespass") into an adjacent area without being offensive.
As a result of his research, Dr. Lewin recommended two different brightness
settings based on whether the EMC was located in an area of high or low
ambient light. After field testing and utilizing Dr. Lewins recommendations,
it was determined that using the more conservative recommendation is
appropriate in areas of both low and high ambient light. In order to simplify
Dr. Lewins recommendations, and to take a more reasonable approach to ensure
that EMCs are sufficiently visible but not overly bright, it is recommended
that EMCs not exceed 0.3 footcandles over ambient lighting conditions
when measured at the recommended distance, based on the EMC 
size.
...it is recommended that EMCs not exceed
0.3footcandles over ambient lighting conditions
when measured at the recommended distance,
based on the EMC 
size.
4. Brightness measurement methodology.
There are two generally accepted measures of brightness in the sign industry;
illuminance and luminance. lUiuninance, the preferred method, is a measure
of the amount oflight intercepting an object at a given distance from a light
source and is measured in footcandles or its metric equivalent, lux. Illuminance
can be measured with a footcandle meter (also know as a luxmeter), which are
relatively inexpensive ($100-1000) and commonly available. The footcandle
merer should be accurate to two decimal points for accurate measurements.
The second method, luminance, is an absolute measure of the amount of
brightness that is being emitted from a light source and is usuaUy measured
in candelas per square merer, also known as "nits." Luminance can be measured
by use ofa "nit gun", which are expensive (-$3,000) and difficult to procure. The
preferred method of measurement is illuminance using a footcandle meter
because a measure of luminance fails to account for ambient light conditions.
ISA • International Sign Association
i,lstrpuma
Summary Report on EMC Brightness Levels

Recommended
Legislative
Language
m.
CC
1. Electronic Message Center (EMC) 
Criteria: The illumination
of an EMC 
shall conform with die criteria set forth in this
section.
A. EMC 
Illumination Measurement Criteria: The illuminance
ofan EMC 
shall be measured with an illuminance meter set
to measure footcandles accurate to at least two decimals.
Illuminance shall be measured with the EMC 
off, and again
with the EMC displaying a white image for a full color-
capable EMC, or a solid message for a single-color EMC.
All measurements shall be taken perpindicular to the face of
the EMC at the distance determined by the total square
footage of the EMC as set forth in the accompanying Sign
Area Versus Measurement Distance table.
B. EMC 
lUumination limits: The difference between the off
and solid-message measurements using the EMC Measurement
Criteria shall not exceed 0.3 footcandles.
C. Dimming Capabilities: All permitted EMCs shall be equipped
with a sensor or other device that automatically determines
the ambient illumination and programmed to automatically
dim according to ambient light conditions, or that can be
adjusted to comply with the 0.3 footcandle measurements.
D. Definition of EMC: A sign that utilizes computer-generated
messages or some other electronic means of changing copy.
These signs include displays using incandescent lamps,
LEDs, LCDs or a fliper matrix.
SIGN AREA VERSUS MEASUREMENT DISTANCE
AREA OF SIGN
sq.it.
MEASUREMENT
Distance (fit.)
10
32
15
39
20
45
25
50
30
55
35
59
40
63
45
67
50
71
55
74
60
77
65
81
70
84
75
87
80
89
85
92
90
95
95
97
100
100
110
105
120
110
130
114
140
118
150
122
160
126
170
130
180
134
190
138
200
141
220
148
240
155
260
161
280
167
300
173
ISA • International Sign Association
A Summary Report on EMC Brightness Levels

EMC Brightness Levels
How to Measure the Brightness
of an Electronic Message Center (EMC)
STEP
OBTAIN AN ILLUMINANCE METER.
Purchase or otherwise procure an illuminance meter. Most dty/coun^' traffic
departments have an illuminance meter, which are also referred to as lux or
footcandle meters (lux is the metric measure ofilluminance; footcandles is the
English measure ofilluminance). The illuminance meter must have the djility
to provide a reading up to two decimal places and must be set to read foot-
candles. It is preferred to have an illuminance meter with a screw-mount that
allows the sensor to be mounted on a tripod. A tripod ensures that the highly
sensitive sensor Is held perfecdy still; otherwise it may be difficult to obtain
an accurate reading.
If you do not have an illuminance meter, the Kbnica Minolta T-10 is a high quality
illuminance meter that works well. However, other less expensive illuminance
meters may also provide adequate results. The International Sign Association
has no affiliation with Konica Minolta.
STEP 2
DETERMINE SQUARE FOOTAGE.
Determine the square footage of the face of the electronic message sign
(EMC) by multiplying the height and width of the EMC. This information
may be available In a permit application, or can be determined by physically
measuring the height and width of the EMC. Do not include the sign face
square footage attributable to any additional static signs associated with the
EMC 
(if applicable).
STEP 3
DETERMINE THE MEASUREMENT DISTANCE
Using the total square footage found in Step 2, look up the measurement
distance in the table provided in the Recommended L^islative Language on
page 6, to determine the distance to measure the brightness of the EMC.
The distance should be measured perpendicular to the EMC sign face. The
use ofa measuring wheel is the most convenient way to measure the distance.
w
 iSi£
ISA • International Sign Association • A Summary Report on EMC Brightness Levels

How to Measure tlie Brightness of an Electronic Message Center
STEP 4
STEP 5 
[CONTINUED:!
PREPARE THE DISPLAY FOR TESTING.
Ensure that the EMC is programmed to alternate between a solid white (or
in the case ofa monodirome display - 
the solid color of the display) message
and a blank message. You may wish to include a provision in your code that
requires the EMCs in your community to be programmed to alternate briefly
(3-5 seconds) between a white message or a blank message for a short interval
at a given time of night, or you may wish to have a requirement that the sign
owner cooperate with testing by programming the EMC for testing upon
written notice.
5
USE AN ILLUMANCE METER TO MEASURE THE BRIGHTNESS
OF THE EMC
Mount the sensor of your illuminance meter to a tripod and orient the sensor
directly towards the face of the EMC at the measurement distance determined
in Step 2.
Ensure that the illuminance meter is set to measure footcandles up to two
decimal places. As the display altematcs between a solid white message and a
blank message, note the range of values on die illuminance merer. Ifthe difference
between the readings is less than 0.3 footcandles, then the brighmess of the
display is in compliance. If not, the display will need to be adjusted to a lower
brightness level using the manufacturers recommended procedures.
Delictoua Menu
fterra to
s.inii\
STEP 6
ENSURE THAT THE DISPLAY CAN ADJUST TO DIFFERENT
AMBIENT CONDITIONS.
Inspect the sign to ensure diat it incorporates a photocell or other technology
to ensure that the display can adjust according to ambient lighting conditions.
As the display alternates betwee^t a solid white
message and a blank message, note the range ofvalues
on the illuminance meter. If the difference between the
readings is less than 0.3 footcandles, then the
brightness of the display is in compliance.
•
 International Sign Association • A Summary Report on EMC Brightness Levels

International
Sign Association
I GDI N. FAIRFAX STREET, SUITE 30 
I
ALEXANDRIA. VA 223 
I A
703.836.6067 PH
703.836.8353 FAX
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i- 16956
SHERWOOD
HIGH
SCHOOL
CLASS OF 2006
Recommended Brightness Levels for On-Premise Electronic Message Centers