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HomeMy WebLinkAbout1480 Burlingame Avenue - Technical Study� Dtech communicafions YOUR RF SAFETY PARTNER RADIO FREQUENCY ELECTROMAGNETIC FIELDS EXPOSURE REPORT Prepared for AT&T c/o Caldwell Compliance Site Name: Central Burlingame Site ID: CCL00566 USID: 13300 FA ID: 10095832 Site Type: Rooftop Located at: 1480 Burlingarne Avenue Burlingame, CA 94010 Latitude: 37.57G9 / Longitude: -122.3498 RECEIVED JUN 3 0 2016 Report Date: 5/27/2016 Report By Jamie Santos CITY OF BURLINGAME CDD-PLANNING D11/. Based on FCC Rules and Regulations, AT&T Mobiliry will be compliant provided recomrnendation(s) are implemented. Page 1 / 15 TABLE OF CONTENTS 1.0 2.0 2.1 2.2 3.0 3.1 3.2 4.0 4.1 4.2 4.3 4.4 EIZECUTIVE SUMMARY ................................................................................................................................3 SITEDESCRIPTION ........................................................................................................................................4 SiteMap .............................................................................................................................................................4 AntennaInventory ...........................................................................................................................................5 ANALYSIS...........................................................................................................................................................6 EmissionPYedictions .......................................................................................................................................6 FivePercent Contributions .............................................................................................................................8 CONCLUSION...................................................................................................................................................9 Results................................................................................................................................................................9 Recommendation(s) .........................................................................................................................................9 Statementof Compliance ............................................................................................................................. 11 EngineerCertification ................................................................................................................................... 11 Append� A: Background ........................................................................................................................................... 12 Appendix B: MeasuYement and/or Computer Simulation Methods ................................................................... 13 AppendixC: Limitations ............................................................................................................................................ 13 AppendixD: AntennaViewO .................................................................................................................................... 14 Append� E: AT&T RF advisory signs .................................................................................................................... 15 • 7 Dtech �°^'m'""�°h°"5 5850 OGerlivr Drive, Ste. 300 ♦ Sait Diego, CA 92121 ♦ 858.792.0066 ♦ www.dtechcom.com Page 2/ 15 1.0 EXECUTIVE SUMMARY Dtech Communications, LLC ("Dtech") has been retained by Caldwell Compliance, contractors to AT&T, to determine whethex its wireless communicarions facility complies with the Federal Communicarions Commission ("FCC") Radio Frequency ("RF") Safety Guidelines. This Yeport contains a computer- simulated analysis of the Electromagnetic Fields ("EMF") exposure resulting from the facility. The analysis also includes assessment of e�sting wireless carriers on site, where information is provided. The table below suinrnarizes the result at a glance: Table 1: EMF Summary Access Type Door Access to antennas locked Recommended RF Si n(s @ access oint s Information 1& Notice ecommended) RF Si n s @ antennas Information 1& Norice ecommended) Barrier s@ sectors Re uired - see Recommendations Max EMF level for 3.5% General Population AT&T on Ground Max curnulative EMF level for 3.6% General Population facili on Ground Max EMF level for 268.6% General Popularion AT&T on Roof 53.7% Occu ational) Max cumulative EMF level for 270.0% General Population facili on Roof 54.0% Occu ational) • , Dtech cor„mur,�conoru 5850 OGerlin D�zue, Ste. 300 ♦ Saif Dlego, CA 92921 ♦ 858J92.00G6 ♦ wavw.dtechcom.can Page 3/ 15 2.0 SITE DESCRIPTION The wireless telecommunication facility is located on a building rooftop. The facility consists of 4 wireless carrier(s) or operator(s): AT&T, T-Mobile, Clearwire & Other(s). The antennas are typically grouped into sectors pointing in different direction to achieve the desired areas of coverage. AT&T's antennas are facade-mounted on the penthouse above the roof and connected to the equipment via cables. 2.1 Site Map . 7 Dtech commu�,;cotro�s 5850 OGerlin Dire�e, Ste. 300 ♦ San Dtego, CA 9?121 ♦ SS8J92.006G ♦ mzvw.dtechcom.con� Page 4/ 15 2.2 Antenna Inventory Technical specifications in the table below are provided by ouY clients or gathered from physical field surveys where applicable and/oY possible. Conservative estimates are used where information is not provided or available. Table 2: Site Technical Specifications Bottom Tp Bottom Tip Antenna Frequency Orientation Horizontal Antenna Antenna 2G/GSM 3G/UMTS 4G/LTE Total ERP Height Abo�e Height Abo�.e ID Operatw Antenna M(g Antenna Model Type (MHz) (°� BWdth (") Aperture (ft) Gain (dBd) Radios Radios Radios (Watts) X Y Ground (A (ft) Roof (� (ft) A1 AT&T Quintel QS665&3 Panel 700 320 65.5 6 10.9 1 741 76 74 77.0 8.8 A1 AT&T Quintel QS665&3 Panel 850 320 64 6 8.4 1 550 76 74 77.0 8.8 A1 AT&T Quintel QS665&3 Panel 1900 320 63 6 15.4 1 2754 76 74 77.0 8.8 A2 AT&T Kathrein 742-265 Panel 850 320 68 6.3 13.4 2 1318 75 73 76.9 8.6 A2 AT&T Kathrein 742-265 Panel 1900 320 65 6.3 16.1 2 3236 75 73 76.9 6.6 A3 AT&T Commscope SBNHH-1DG58 Panel 850 320 66 6.1 122 2 661 73 71 77.0 8.8 A3 AT&T Commscope SBNHH-1D65B Panel 2100 320 63 6.1 16.1 1 4898 73 71 77.0 8.8 A4 AT&T Quintel QS6658-3 Panel 700 320 65.5 6 10.9 1 741 72 69 77.0 8.8 A4 AT&T Quintel QS665&3 Panel 2300 320 60 6 162 1 4169 72 69 77.0 8.8 B1 ATBT Quintel QS665&3 Panel 700 200 65.5 6 10.9 1 741 35 52 77.0 8.8 81 ATBT Quintel QS665&3 Panel 850 200 64 6 8.4 2 275 35 52 77.0 8.8 81 AT&T Quintel oS665&3 Panel 1900 200 63 6 15.4 1 2754 35 52 77.0 8.8 62 AT&T Quintel QS665&3 Panel 850 200 64 6 8.4 1 550 37 50 77.0 8.8 62 ATBT Quintel QS66583 Panel 2300 200 60 6 162 1 4169 37 50 77.0 8.8 83 AT&T Commscope SBNHH-1D65B Panel 700 200 66 6.1 12.4 1 1047 64 31 77.0 8.8 83 AT&T Commscope SBNHH-1D65B Panel 2100 200 63 6.1 16.1 1 4898 64 31 77.0 8.8 84 AT&T Kathrein 742-265 Panel 850 200 68 6.3 13.4 2 1318 67 29 76.9 8.6 84 AT&T Kathrein 742-265 Panel 1900 200 65 6.3 16.1 2 3236 67 29 76.9 8.6 C1 AT&T Kathrein 742-265 Panel 850 80 68 6.3 13.4 2 1318 77 25 76.9 6.6 C1 AT&T Kathrein 742-265 Panel 1900 80 65 6.3 16.1 2 3236 77 25 76.9 8.6 C2 AT&T Quintel QS665&3 Panel 700 80 65.5 6 10.9 1 741 79 28 77.0 8.8 C2 AT&T Quintel QS665&3 Panel 850 80 64 6 6.4 1 550 79 28 77.0 8.8 C2 AT&T Quintel QS665&3 Panel �900 80 63 6 15.4 1 2754 79 28 77.0 8.8 C3 AT&T Commscope SBNHH-1D658 Panel 850 80 66 6.1 122 2 661 87 45 77.0 8.8 C3 AT&T Commscope SBNHH-1D658 Panel 2100 80 63 6.1 16.1 1 4896 87 45 77.0 8.8 C4 ATBT Quintel QS66583 Panel 700 80 65.5 6 10.9 1 741 83 47 77.0 8.8 C4 AT&T Quintel QS66583 Panel 2300 80 60 6 16.2 1 4169 83 47 77.0 8.8 1 T-Mobile Unknown Unknown Panel 1900 30 80 4 15 - - - 1500 46 73 76.2 8.0 2 T-Mobile Unknown Unknown Panel 1900 150 80 4 15 - - - 1500 87 42 762 8.0 3 T-Mobile Unknown Unknown Panel 1900 2�0 80 4 15 - - - �500 29 58 76.2 8.0 t Cleaiwire Unknown Unknown Panel 2500 30 80 4 14 - - - 1500 43 75 78.2 10.0 2 Cleaiwire Unknown Unknown Panel 2500 150 80 4 14 - - - 1500 86 40 782 10.0 3 Clearwire Unknown Unknown Panel 2500 270 80 4 14 - - - 1500 29 55 782 10.0 1 Others Unknown Unknown Dish 10000 0 2 2 38 - - - 65 34 64 78.2 10.0 2 Others Unknown Unknown Dish 10000 180 2 6 38 - - - 65 69 27 782 10.0 1 Others Unknown Unknown Whip 850 0 360 8 8 - - - 315 72 27 83.2 15.0 2 Others Unknown Unknown Whip 850 0 360 8 8 - - - 315 80 33 83.2 15.0 / , Dtech commun�coians 5850 OGerlin Drive, Ste. 300 ♦ San Diego, CA 92121 ♦ 858J92.0066 ♦ ivivlv.dtechcom.com Page 5/15 3.0 ANALYSIS 3.1 Emission Predictions Figure 1: Plan (bird's eye) viezv map of re.rults compared to FCC's General Population MPE (Maximum Perjnis.rible E.x�o.rzare) Limits. Gray repre.rent.r area.r �vhere e.xposure levels are calc•ulated to be at or belozv 5%; Green- betzveen 5% d�' 100% (belozv MPE limits); blue, yelloav e�' red — greater than 100% (exceeds MPE limit.r�. %of FCC General Public Exposure Limit � X 5 5 ■ 5< X s 100 ■ 100 < X s 500 � 500 < X 5 5,000 ■ X> 5,000 AT&T: Simulation Diagram /� Oround Level Max Sim Levels N Elevation:0� AT8.T:3.5'/• Grid Size = 20 ft Cumulative: 3.6°k I I ' ' �, AT&T 12g,Clearwire 3 � L; T-Mobile l 3 O, Omni 2 Dish 2 � 7 Dtech commw,rcoron: 5850 OGerlin Drive, Ste. 300 ♦ Sm: Diega, CA 92121 ♦ 858.792.0066 ♦ mmm.dtechcom.coir� Page 6/15 Figure 2: Plan (bird'.r eye) vieu� nrap of results compared to FCC's General Population MPE (Maximarm Permissi�le E.xjiosicre) Limit.r. Gray repre.rents area.r zvhere e.�osirre levels are calculated to be at or beloaa� 5%; Green- betaa�een 5% e�' 100% (belozv MPE limit.r); blue, yellozv d�' red — greater than 100% (exceeds MPE limits�. °k of FCC General Public Exposure Llmit � X s 5 ■ 5< X s 100 ■ 100 < X s 500 � 500 < X s 5,000 ■ X> 5,000 AT&T: Simulation Diagram � I I � '� � ' i �� � �I � 1 I � I I � � � Dtech canmuNcatbns 5850 OGerlin Drive, Ste. 300 ♦ Sa�t Diego, CA 9212> ♦ 858.792.0066 ♦ iv:v:v.dtechcom.rom Page 7/15 � � �, / Roof Level Max Sim Levels I�; AT&T 12',� Clearwire' 3 N% Elevation:68.2� ATBT: 268.6% � T-Mob�le 3 io Omn�-__ I 2 � Cumulative:270.0'k � _ crid s�ze = zo n ♦ Dish � 2 I 3.2 Five Percent Contributions Mitigation measures axe a shared responsibility for carriers whose RF emission levels exceed five percent of the FCC's exposure limits in areas of non-compliance. Figzare 3: Plan (bird's eye) viezv map of results compared to FCC'.r General Population MPE (Maximum Permissible E.�cpo.rure) Limitf. Gray repre,rentf areas aa�here e.x�o.rure levels are calcirlated to be at or beloa.v 5%; Green — greater than 5%. %of FCC General Population Exposure Limit � Xs5 ■ X>5 . -- — --- - --- — � AT&T: Simulatton Diagram , ' i i � � Roof Level �; AT&T 12T� Clearwire 3 N Elevation:68.2' !' T-Mobile 3 O Omni 2 crid s�ze = zo tt IT. Dish I 2 • , Dtech ccM,murr,�ccanons 5850 O�erliaJ Drive, Ste. 300 ♦ San Dlego, CA 92121 ♦ 858.792.0066 ♦ tvmw.dtechcom.com Page 8/ 15 � _ i_ I _ 4.0 CONCLUSION 4.1 Results For a person standing in accessible areas on the ground, calculations for AT&T's site including contriburions from e�sting carriers resulted in exposure levels below the FCC's most stringent General Population MPE Lunits (see figure 1). For a person standing on the roof, the highest calculated exposure level is above the FCC's General Population MPE Lunits near the AT&T antennas (see figure 2). There may be situations where workers i.e. window washers, painters, roofers, etc., may find themselves direcdy in front of the antennas. Individuals entering the site or working near/in front of antennas must receive appropriate RF safety training' and be made aware of the HotZones (areas where RF exposure may potentially exceed FCC safety limits). In addirion, contact informarion should be made available in the event work is required within the HotZones. 4.2 Recommendation(s) The following compliance action(s) would be sufficient to meet the FCC's and AT&T's RF Safety Guidelines2 (see figure 4): 1) Access to the roof deck must be kept locked to restrict routine access by the general public. 2) Install INFORMATION Sign 1 and NOTICE Sign(s) at antenna access points, gate entrances or climbing access points. 3) Install appro�mately an 8-foot by 20-foot barrier, fence or paint striping in front of sector A to demarcate the HotZones. 4) Install approximately an 8-foot by 16-foot barrier, fence or paint striping in front of sector B1 /B2 antennas to demarcate the HotZones. 5) Install approxunately an 8-foot by 16-foot marking or paint striping in front of sector B3/B4 to demarcate the HotZones. Note: marking or paint striping would be more appropriate since the restricted area is uninediately outside the roof access door. 6) Install approximately an 8-foot by 14-foot barYier, fence ox paint striping in front of each pair of sector C antennas to demarcate the HotZones. 7) Install NOTICE Sign(s) and INFORMATION Sign 1(s) on, or proximal to the barriers3. The signs must be visible from any direction prior to entering the HotZones. Note: per OSHA safety requirements, if a physical barrier i.e. stanchions with chains, is unplemented (as opposed to paint striping), then unanchored objects such as stanchions must be placed no closer than 6 feet from an unpxotected roof edge where the paYapet height is lower than 36 inches. � See Appendix for Dtech's 12F Safety training program - AntennaView� 2 A'TT-002-290-078 RF Exposure: Responsibilities, Yrocedures Rc Guidelines — September 2012 3 Barrier(s) must be built according to OSHA unprotected roof edge standazds. • � Dtech commu�Kanons fg50 OGerlin D�zve, Ste. 300 ♦ Sai! Diego, CA 92121 ♦ 858.792.0066 ♦:vww.dtechcom.can Page 9/15 Figure 4: Kecommendation(.r) ATBT: Recommendation Diagram � �� �, `----'i �.� p f .\ (a. �q' � Ta410 �`'F ,qt \ EQ � �/ �T l�� % / ' p�e'�j , ! t // �` Cy� Roof Level \� /� �� � ��� js, \ `\ �� d°''.� ,� � Roof Levei � , Penthouse �. 14• ----- � �d..�� \. _..._.. � ,� � BZ ,-" '"_"`'�r����a \ �]a � � , - _ \ �j - „ � ,� , C �.. � � ' :� = � � � _ , � , - - - . . - �' - - -- � . _ , _ ' / ��� ' /��� - ----- � :- � _ _ /, �,,// � � I _- — _ �� ` ��Access � 8 _ � �� Door n' ' - \ � rs• 1��5��/� _ - M -- � _ _ I : \ fRS7rS� � - _ � `--- ------I-- ----- '— I � N% Cxid Size � 20 R _i I I � i 'a; AT&T 12��Clearwire 3 ', i�; T-Mobile; 3� Omrn 2� ; Dish 2 � , Dtech commwucar,ors 5850 OGerlin DriUe, Ste. 300 � Sa�J Diego, CA 92121 ♦ 858J92.0066 ♦ tvww.dtechcom.coirr Page 10/ 15 � NStigetian ereas: exess ��: to these areas shall be � � restricted. `-L-- --� 4.3 Statement of Compliance Based on the above results, analysis and recommendation(s), it is the undersigned's professional opinion that AT&T Mobility's site including contributions from existing carriers wi]1 be compliant with the FCC's RF Safety Guidelines provided recommendarion(s) are implemented. 4.4 Engineer Certifcation This report has been prepared by or under the direction of the following Registered Professional Engineer: Darang Tech, holding California registration number 16000. I have reviewed this report and believe it to be both true and accurate to the best of my knowledge. / ,�� Daran Tec , P.E. a - • � a000 " s � E�•�� 3 * t�`� �,� * �'1' FcT��G �r �� CAI�F�% . 7 Dtech communicoiions 5850 OLerlin D�zue, Ste. 300 ♦ Sau Diego, CA 92121 ♦ 858J92.006G � 1YW7KlIICCJJL'0I77.00/IY Page 11 / 15 Append'u� A: Background Dtech uses the FCC's guidelines described in detail in Office of Engineering & Technology, Bulletin No. 65 ("OET-65") "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields". The table below suinmarizes the curYent Maxixrium Permissible Exposure ("MPE") safety limits classified into two groups: General population and Occupational. Table 3: FCC MPE Limits (from OET-65) ���� :�' 'u�� �� `; � . � � . '9 � . . � A. 1 . 1 1 ,l, �� � a� � � 30 - 300 0.2 30 1.0 6 300 - 1500 Frequency (Mhz)/1500 30 Frequency (Nlhz)/300 � 0.2 — 1.0) 1.0 — 5.0) 1500 - 1.0 30 5.0 6 100,000 General population/uncontrolled limits apply in situations in which the general public may be exposed or in which persons who are exposed as a consequence of their employment, and may not be fully a�vare of the potential for exposuxe or cannot exercise control over their exposure. Therefore, members of the general public always fall under this category �vhen exposure is not employment-related. Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their employment, and those persons have been made fully aware of the potential for exposure and can exercise control over their exposure. Occupational/controlled limits also apply where exposure is of a transient nature as a result of incidental passage through a location where exposure levels may be above general population/uncontrolled limits, as long as the exposed person has been made fully awaYe of the potential for exposure and can exercise control over his or her exposure by leaving the area or by some other appropriate means. It is important to understand that the FCC guidelines specify e.a�o.rarre limits not emi.rsion limits. For a transmitting facility to be out of compliance with the FCC's RF safety guidelines an aYea ox areas whexe levels exceed the MPE limits must, first of all, be in some way acce.r.rible to the public or to workexs. When accessibility to an area where excessive levels is appropriately restricted, the facility or operation can certify that it complies with the FCC requirements. � , Dtech commurycatbns fg50 OGerlin D�zve, Ste. 300 ♦ San Diego, CA 92121 ♦ SSSJ92.0066 ♦ lvsvm.dtec•hcom.coirr Page 12/15 Appendi�c B: Measurement and/or Computer Simulation Methods Spatial averaging measuYement technique is used. An area between 2 and 6 feet, approximately the size of an average human, is scanned in single passes from top to bottom in multiple planes. When possible, measurements were made at very close pxoximity to the antennas and inside the main beam where most of the energy is emitted. The spatial averaged values were recorded. Dtech uses an industry standard power density prediction computer Mode14 to assess the �vorse-case, cumulative EMF impact of the surrounding aYeas of the subject site. The Model does not take into account losses due to buildings. Its methodologies are conservative enough to account for typical down-tilts deployed in wireless communications. In addirion, the analysis is perforxned at 100% duty cycle-all transmitters are acrive at all times and transmitting at maxirnum power. For purposes of a cumulative study, nearby transmitters are included where possible. The result is a surxounding area map color-coded to percentages of the applicable FCC's MPE Lunits. A result higher than 100% exceeds the Lunits. Appendix C: Limitations Dtech performed this analysis based on data provided by our clients that Dtech believes to be true and correct. Estimates where noted, are based on common industry pYactices and our best interpretation of available informarion. As mobile technologies continuously change, these data and xesults may also change. Therefore, Dtech disclauns all other warranties either expressed or ixnplied. Any use of this docuxnent constitutes an agreement to hold Dtech and its employees harmless and indemnify it for any and all liability, clauns, demands, litigation expenses and attorneys fees arising from such use. This is a technical document and may contain minoi grammarical and/or spelling eYYOYs. '� Roofview� �'ersion 4.15, Richard Tell Associates, Inc. � 1996-2000. � � Dtech commurucaroru 5850 OGerli�r Dizue, Ste. 300 � Sa�r Diego, CA 92121 ♦ 858J92.0066 ♦ wmsv.dtechcom.coirr Page 13/ 15 � 1, . Appendix D: AntennaViewOO Dtech Communications offers a unique, online tool (AntennaViewOO ) to train, idenrify and inform individuals of site-specific HotZones — areas that may potentially exceed the FCC's Safety Limits. AntennaViewOO is an online, interactive training tool that will educate nontechnical people in about ten minutes. It is a site-specific, RF safety training program that requires the end user to sign an online agYeement thereby limiting the liability to the landloYd and carriers. Some of the advantages include: � Vi�tual walk-thxough in 3-D with corresponding photographs • Site-specific, interactive, simple to understand • Delivers pertinent informarion i.e. HotZones (areas that may potentially exceed FCC safety limits), site owners and contact numbers. • User online agreement = accountability We invite you to take a quick tour at www.AntennaVie�v.com and see how easy to undexstand and informative AntennaViewOO is. UnderArticle 47 CFK �' �. �307(b), the FCC d�' OSHA mandate.r zvirele.r.r operators/facility ozvners to have an KF siiruey com�ileted inclu�ling a.rafety plan and training to ensure that their tenant.r, employee.r and contrac•tor.r zvho zvork in or around K F.rites are aaa�are of the potential risks po,red 6y AF' radiation. Most cell sites are located on birilcling rooftops zvhere HVAC contractor�; zvindoav zvashers, painter,r, etc. routinely zvork andgenerally do not knozv avhat antennas even look like. Dtech Communication.r can he p avith ongoing FCC/ OSHA compliance and provide practical training that i.r easy to under.rtand by anyone regardless of their technical background. . 7 Dtech canmunicohons 5850 O�erlin Drive, Ste. 300 ♦ San Dlego, CA 9?121 ♦ 858J92.0066 ♦ ivwsv.dtechconr.cons Page 14/15 � . r Appendix E: AT&T RF advisory signs � ISevoad This Point.�..�me rni.mn�;:m:�m »h.,c Hi I:mi.vi�na m:n'r.r«edlhe K't' (k�ix-nl I'orulutwm f_ywime limiu Ir4• ill f+^ W•�L�. m, w� N:Mm Notice Sign caurioN �� � i<<i>>) FksonJ This Puinbou.,..� k,;��� � ��m�mii ti .r� wh���.� R( Fmi..iimy mm� e<rerd �hc fCC ckcupatinnul Erc{Knum I.imit. f14.��v �Me.��im��v�U�i.n.. Caution Sign Informarion Sign 1 •`�, � ��� Information Sign 3 Information Sign 4 � , Dtech canmurvcoM1or�s SSSO OGerfirt Drive, Ste. 300 ♦ Sa�r Diego, CA 92121 ♦ 858J92.00G6 ♦:vwu�.dtechcom.cam Page 15/15 __ _. WARNING i8cyond This Point>�w ��.• ient¢ring a convolleJ nrea wherc iRF @missions esccTd the F'CC CoNrolled G:sq+surt I,imits i�il�n N obef all p..vJ .i�n, viN .i�.� �F�Wr�iMs cwW rt�ull in �v� mjun Warning Sign QCAUTION (t�;��) o� vn. awe,. �,b Mq�ency bllf ner fom� may r�CwE FCC 1Wa+ w iwm.n a.w+ur. Caution Sign Alternate for Towers �crr�u�ronusr�iawrtm 0 a�n�a�F�c�o�nas�aa�c � 8ENN0 TfpS PAI�1 � ON ib5 STA�CIUlE SfAYa1CIlAIWAAIY �1FEEf flI0�1fESE AXIENIAS ia�acAT611kaitiryy ndbbr Mt iou�tan pa ropelomigrq maYn�a mrtp�rsdmla� 3kdknlea� ihe eA1f1Y0BUtt�i y�� o..».v miwe Information Sign 2 5 . A • A ) i C { O 1 , . : ;