TheLIGHTING

AUTHORITY

IESNA G-1-03

Guideline for SecurityLighting forPeople,Property, andPublic Spaces

Guideline for SecurityLighting forPeople,Property, andPublic Spaces

IESNA G-1-03

IESNA G-1-03

Guideline for

Security Lighting for

People, Property, and Public Spaces

Publication of this Committee Report has been approved by the IESNA. Suggestions forrevisions should be directed to the IESNA.

Prepared by:IESNA Security Lighting Committee

Copyright 2003 by the Illuminating Engineering Society of North America

Approved by the IESNA Board of Directors, March 1 , 2003 as a Transaction of the Illuminating EngineeringSociety of North America.

All rights reserved. No part of this publication may be reproduced in any form, in any electronic retrieval systemor otherwise, without prior written permission of the IESNA.

Published by the Illuminating Engineering Society of North America, 120 Wall Street, New York, New York 10005.

IESNA Standards and Guidelines are developed through committee consensus and produced by the IESNAOffice in New York. Careful attention is given to style and accuracy. If any errors are noted in this document, pleaseforward them to Rita Harrold, Director Educational and Technical Development, at the above address for verifi-cation and correction. The IESNA welcomes and urges feedback and comments.

ISBN # 0-87995-190-7

Printed in the United States of America.

DISCLAIMERIESNA publications are developed through the consensus standards development process approved by theAmerican National Standards Institute. This process brings together volunteers representing varied view-points and interests to achieve consensus on lighting recommendations. While the IESNA administers theprocess and establishes policies and procedures to promote fairness in the development of consensus, itmakes no guaranty or warranty as to the accuracy or completeness of any information published herein.

The IESNA disclaims liability for any injury to persons or property or other damages of any nature whatso-ever, whether special, indirect, consequential or compensatory, directly or indirectly resulting from the pub-lication, use of, or reliance on this document

In issuing and making this document available, the IESNA is not undertaking to render professional or otherservices for or on behalf of any person or entity. Nor is the IESNA undertaking to perform any duty owed byany person or entity to someone else. Anyone using this document should rely on his or her own indepen-dent judgment or, as appropriate, seek the advice of a competent professional in determining the exerciseof reasonable care in any given circumstances.

The IESNA has no power, nor does it undertake, to police or enforce compliance with the contents of thisdocument. Nor does the IESNA list, certify, test or inspect products, designs, or installations for compliancewith this document. Any certification or statement of compliance with the requirements of this document shallnot be attributable to the IESNA and is solely the responsibility of the certifier or maker of the statement.

IESNA G-1-03

Prepared by the Security Lighting Committee, and Sub-Committee on RelationshipBetween Lighting and Crime, Illuminating Engineering Society of North America.

Committee Members:David L. Salmon, Ph.D., CPO, Chair 1998 2002Brian J. Scanlon, Chair 2002 Theodore Ake, LCCraig R. Bertolett, Sr.**Norman R Bottom, Ph.D., CPP, CPODavid Crawford, Ph.D., FIESRobert DanielsDavid DeanL. Vern ForemanJohn G. Hayes, Ph.D., CPPJames HominsGary HovaterFred D. JusticeRobert E. KaeserHyman Kaplan, L.C., P.E.Lorence E. Leetzow*Robert LovelaceDouglas W. PaulinJeffrey RocheMike RossDavid L. Salmon, IIC. Stanley Stubbe*David Stymiest P.E., SASHE, CEM *C. S. ThomasTimothy J. Walsh, CPP

* Advisory** Honorary

Sub-Committee Relationship Between Lighting and CrimeDavid L. Salmon, II, ChairNorman Bottom, Ph.D., CPP, CPORobert E. KaeserDavid L. Salmon, Ph.D., CPO Brian J. Scanlon

Editing Task GroupTheodore Ake, LC, ChairPeter BoyceDouglas W. PaulinBrian J. Scanlon

IESNA G-1-03

Table of Contents

Foreword and History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Lighting and its Relationship to Crime. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.0 Scope and Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3.0 Basic Principles of Security and Security Lighting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.2 Community Responsive Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43.3 Security Lighting Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4.0 Understanding When Security is an Issue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

5.0 Visibility Concerns in Security Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65.1 Illuminance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65.2 Horizontal Illuminance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.3 Vertical Illuminance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.4 Uniformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.5 Glare. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.6 Shadows. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.7 Establishing Site Divisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.8 Total Site Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.9 Pedestrian Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.10 Pedestrian Path Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.11 Building Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.12 Building Perimeter Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

6.0 Lighting Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

7.0 Security Lighting for Controlled Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207.2 Specific Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

7.2.1 Unoccupied Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227.2.2 Offices and Other Buildings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237.2.3 Automated Teller Machines and Night Depositories . . . . . . . . . . . . . . . . . . . . . . . . . . 257.2.4 Parking Facilities (Lots and Garages) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277.2.5 Residential Parking Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277.2.6 Parking Lots and Areas for Public Parks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287.2.7 Supermarkets and Major Retail Outlets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287.2.8 Fast Food and Franchise Restaurants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297.2.9 Convenience Stores and Gas Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307.2.10 Single-Family Residences. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317.2.11 Multi-Family Residences and Dormitories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327.2.12 Multi-Family Residences for the Elderly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337.2.13 Schools & Institutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347.2.14 Law Enforcement, Fire, Ambulance, and Other Emergency Services . . . . . . . . . . . . . 347.2.15 Hotels and Motels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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8.0 Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Annexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Annex A-Studies on Lighting and its Relationship to Crime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Annex B-Physical Security Survey. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Annex C-Taking Security Illumination MeasurementsA Practical Guide . . . . . . . . . . . . . . . . . . . . . . 44Annex D-Crime Analysis and Foreseeability of Crime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Annex E-Crime Prevention Through Environmental Design [CPTED] . . . . . . . . . . . . . . . . . . . . . . . . . 52Annex F-Lighting for Television and Photographic Surveillance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Annex G-Municipal Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Annex H-Additional Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

IESNA G-1 Security Lighting for People, Property,and Public Spaces

Foreword and History

During World War I, the U.S. Government recognizedthe need for industry to increase exterior lighting atkey production facilities, docks, assembly yards, highsecurity facilities, and railway yards. These improve-ments had two purposes, to aid in production, and todeter sabotage. Although exterior protective lightingwas widely increased, no standard was set.

With the advent of World War II, at the request ofthe War Department, Military Intelligence, withassistance from the Insurance Committee for theProtection of American Industrial Plants, and theAmerican Standards Association (ASA), initiated aproject to develop a standard on outdoor protectivelighting for industrial properties. The primary pur-pose of these efforts was to prevent theft and sab-otage. Additionally, it was soon realized that lightdiscipline was important to the war effort. Coastalfacilities were darkened, and stray light was strictlycontrolled. North America was learning the impor-tance of good security lighting and lighting disci-pline.

During 1942, the ASA War Standards Procedurewas applied, and a War Standards Committee pre-pared and published American Standard, A85-1942, Protective Lighting for Industrial Properties.This eventually became an ANSI Standard.

In 1948, the ASA Safety Code CorrelatingCommittee terminated War Standards and institut-ed a revised standard for peacetime use. TheIlluminating Engineering Society was designatedAdministrative Sponsor for this effort.

The IES Protective Lighting Committee developedthe first draft of this revision, which the SectionalCommittee used as a basis for an AmericanNational Standard Practice.

In 1977, The Protective Lighting Committee, IES,sponsored, wrote, and published AmericanNational Standard Practice for Protective Lighting-RP-10. This standard was intended as a guide foroutdoor protective lighting to those responsible forplant protection.1

In 1994, a Security Lighting Committee was formedby the IESNA. Its first project was to write a mod-ern guideline for security lighting for North America.

During 1997-1998, the Security Lighting Committee

developed material that was the basis for Chapter29 of the IESNA Lighting Handbook, Ninth Edition.2

During 1999, members of the Security LightingCommittee outlined the contents and approach fora guideline for peer review and comment beforeseveral professional groups. These groups includ-ed the American Society of Safety Engineers, andthe American Society for Industrial Security.

During 2000, additional presentations were madebefore professional security groups concerned withthe safety and security of the public, including theInternational Conference on Shopping Centers andthe American Society of Industrial Security.

1.0 INTRODUCTION

The Security Lighting Committee, previously knownas The Protective Lighting Committee of theIlluminating Engineering Society of North America(IESNA), was established to generate and developcriteria for lighting to enhance the security of peopleand property, to recommend the integration and inter-action of lighting as part of a total security system, andto write a publication.

1.1 Lighting and its Relationship to Crime

The possibility that lighting might have an impact onthe incidence of crime was a topic of interest in theUnited States in the sixties. Municipalities acrossAmerica improved their street lighting to combat crimeand some encouraging results were reported, but onreview there was no significant statistical evidence thatimproved street lighting influenced the level of streetcrime. There was, however, an indication that theimproved street lighting decreased the fear of crime.

Twenty years later, in 1988, a before and after relight-ing study of a street in the outer city area of London,England, by K. Painter demonstrated a marked reduc-tion in the incidence of crime and the fear of crime onthe relighted street. (See Annex A.)

This lead to an outburst of similar studies in the UK byPainter (1989, 1991, 1994), Barr and Lawes (1991),Burden and Murphey (1991), Davidson and Goodey(1991), Herbert and More (1991), Glasgow CrimeTeam (1992, Nair (1993), Ditton and Nair (1994) andCridland (1995). The results were mixed.

The most sophisticated study undertaken on the effectof lighting on the incidence of crime was in 1999 inStoke-on-Trent in England by Painter and Farrington.

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Three areas of housing were selected; one was theexperimental area where the lighting was improved;one was designated the adjacent area; the third wasthe control area, which served as the baseline againstwhich any changes in crime could be monitored. Thelighting in the adjacent and control areas remainedunchanged. One aspect of the study was to see ifimproved lighting in one area might lead to similar ben-efits of crime reduction in the adjacent area. There wasa marked reduction in the prevalence of crimes suchas theft and vandalism, vehicle crime, and personalcrime in the experimental area after relighting. Therewas no significant change in the adjacent or controlareas. A similar study in the town of Dudley, England,showed that the level of delinquency decreased morein the relighted area than in the control area.

The results of all these studies indicate that lighting hasa place to play in crime prevention. A list of sources forfurther reading may be found in Annex A. While thereare no guarantees that improved lighting will cause adecrease in crime, there are circumstances in whichlighting can be an effective crime countermeasure,either alone or in combination with other measures.

Lighting can affect crime by two indirect mecha-nisms. The first is the obvious one of facilitatingsurveillance by the authorities and the communityafter dark. If such increased surveillance is per-ceived by criminals as increasing the effort andrisk and decreasing the reward for a criminal activ-ity, then the level of crime is likely to be reduced.Where increased surveillance is perceived by thecriminally inclined not to matter, then better light-ing will not be effective.The second mechanism bywhich an investment in better lighting might affectthe level of crime is by enhancing community con-fidence and hence increasing the degree of infor-mal social control. This mechanism can be effec-tive both day and night but is subject to manyinfluences other than lighting.

2.0 SCOPE AND PURPOSE

The primary purpose of this publication is to establishguidelines for the design and implementation of securi-ty lighting.* It addresses security illumination but doesnot give advice on construction practices. The objectiveis to provide guidance for designing security lightingsystems for new facilities and for evaluating existingfacilities and systems. This publication is intended for

the use of property owners and managers, crime pre-vention specialists, law enforcement and security pro-fessionals, risk managers, lighting specifiers, contrac-tors, the legal profession, and homeowners who areconcerned about security and the prevention of crime.Crime, its prevention, and the application of lighting tohelp minimize criminal activity, are considered in a lesstechnical and user-friendly manner for the benefit ofproperty owners, but illuminating engineers, architectsand other professionals should find the concepts usefulto review with their clients.

The primary measurement references throughout thisdocument are metric, with the English equivalent inparenthesis. For example, 1.5 meters will be dis-played as 1.5 m (5 ft), and 100 lux will be displayed as100 lux (10 fc). These conversions are approximate,but considered sufficiently accurate in this context.

In this publication will be found a discussion of basicsecurity principles, illuminance requirements for vari-ous types of properties, a protocol for evaluating cur-rent lighting levels for different security applications,and security survey and crime search methodology.The guidelines are based on consensus among mem-bers of the IESNA Security Lighting committee andother security experts.

Suggestions are given for exterior and interior securi-ty lighting practices for the reasonable protection ofpersons and property. This document also promotesa concept of best practice, which takes into accountthe following lighting design issues:

Economics (including cost, maintenance and oper-ational costs)

Environmental issues (including light pollution, lighttrespass and the adverse effects of light on animalsand plants)

Municipal lighting ordinances, by-laws or codes Energy conservation, and maintenance requirements

Minimum guidelines for the safe movement of per-sons and equipment and for performing specific taskscan be found in other IESNA publications. This docu-ment is intended to provide specific guidelines whereit has been determined that security is an issue, andwhere security is an important determining factor inthe design or retrofit of a given property.

Note that throughout this guideline the phrasewhen security is an issue is used to differentiatethe lighting design suggestions presented hereinfrom those contained in other IESNA publications.While these other publications may make refer-ence to security, in G-1 it is the only issue. Note toothat when security is an issue, not only lighting,

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*Note the distinction made in this document between security lighting and lighting for

safety. Security lighting is intended to protect people and property from criminal activities.Lighting for safety is intended to provide safe working conditions, safe passage and iden-tification of hazards or obstructions.

but all measures and system components areincreased and/or strengthened; for example, per-sonnel, surveillance, gates, locks, and fences.

Security lighting, as part of a well-balanced securityplan, should have the following objectives:

1. Provide a clear view of an area from a distanceand enable anyone moving in or immediatelyaround it to be easily seen

2. Deny potential hiding spaces adjacent to fre-quently traveled foot routes

3. Permit facial identification at distance of at least9 m (30 ft), and create the perception of beingidentifiable

4. Facilitate the proper use of other securitydevices available on the property

5. Deter crime against persons or property6. Enhance the publics feeling of comfort in

accessing spaces and increase night-timepedestrian traffic

3.0 BASIC PRINCIPLES OF SECURITY ANDSECURITY LIGHTING

3.1 PrinciplesSecurity lighting is installed to help protect people andproperty from criminal activities, and to create a per-ception of security. To better understand the principlesof security lighting, it is first appropriate to look at sev-eral key security tenets.

Responsibility - In North America, the burden of secu-rity and safety is generally placed on the individualswho have primary control over a given property. Withthe rights of control comes the responsibility of con-trol. For example, a property owner can enforce rulesof trespass, install security systems, restrict access,and make other decisions that may have far reachingconsequences for those who access the property. Toa lesser degree, a tenant of the property may share inthis control and responsibility for the sublet space.Owners and operators have or should have, a superi-or knowledge of the sites history, including crime.Casual visitors, invitees, or customers generally haveno responsibility for security at a given site since theyare not able to exercise reasonable control over theevents at the location, or influence the environment. Itis generally the responsibility of a resident, businessoperator, or property owner to provide for the safetyand protection of human life and the property.

Anticipating the threat - A helpful approach in deter-mining the security needs of a property or operation isto study the opportunity, means, and motivation of

potential perpetrators. Security works to deny oppor-tunity, and increase the level of means or resourcesnecessary for the criminal to successfully attack thetarget, and escape. When opportunity is limited, and alarge amount of time and resources are required tosuccessfully complete a criminal act and escape,criminal motivation declines.

Time - Time is the criminals enemy. The longer acriminal act takes in planning, execution, and escape,the more likely the crime will be deterred. Most com-mon criminals will choose a property that requires theleast amount of stealth, equipment, and planning.

Target hardening - A target is harder to attack whencoordinated security elements are provided. In theprocess of target hardening, deterrent objectives areset, options reviewed, and steps taken to improvesecurity. The target is the people or property to be pro-tected, and the various security features are the hard-ening elements. Each separate security element addsto the others, making the target harder to attack.Security elements available to the professional will varyby situation, but often include management controls,perimeter protection, a means of surveillance,response capabilities, and security lighting. A goodsecurity plan will contain layers of security features, andwill not rely on one single security feature for success.

Fight or flight - The basic decision made by personswhen threatened is fight or flight. In other wordsisdefense or evasion the appropriate measure?Sometimes, the act of fleeing danger is simply not anoption due to circumstances. Fight may be the physi-cal act of defense or a call for help. For police or secu-rity officers, it usually means some form of physicaldefense for serious threats. Flight, on the other hand,may mean moving to a safe place, or getting out of theway of a presumed threat. Lighting, if properlyinstalled and maintained, can play an important role inhelping people make this basic decision.

Security elements - Security elements can be active orpassive deterrents. Active elements have the capacity tointeract with persons or generate a response to a crimi-nals actions. Passive elements include those securityfeatures and applications that are static in nature and donot interact with a would-be intruder or criminal.

Passive elements for a home or business may includedeterrent features such as perimeter fencing or walls,open or barrier landscaping, exterior and interior illumi-nation systems, safes, open areas, and warning signs.

The most active deterrent is a patrol officer. The effec-tiveness and response of uniformed individuals mak-ing patrol rounds is often hard to predict, causing a

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would-be criminal to pause. Other active applications,in wide use, include: interactive alarm systems, cardor coded entry devices, metal detectors, security andpolice officers, and trained animals such as dogs andgeese. Some elements may be classified as bothactive and passive deterrents. For example, moni-tored closed-circuit television (CCTV), where there isa response or interactive capability is active, whereasCCTV that is not monitored is passive.

Illumination as a key element in security design -Security lighting is usually passive in application.Exceptions to this general rule include luminaires thatare automatically turned on and off by electronicmotion sensors. By applying both passive and activeelements to some security lighting applications, thedesigner can create uncertainty in the mind of thewould-be criminal about being detected and observed.

The principles of security lighting applicable to newfacilities, or existing facilities, those being upgraded,or converted, include:

Integration of illumination into the total security sys-tem, thereby facilitating the effectiveness of othersecurity devices or procedures;

Illumination of objects, people, and places to allowobservation and identification, thereby reducingcriminal concealment;

Illumination to deter criminal acts by increasing fearof detection, identification, and apprehension;

Lessening the fear of crime by enhancing a per-ception of security;

Illumination that allows persons to more easilyavoid threats, and to take defensive action whenthreats are perceived.

3.2 Community Responsive Design

Community responsive design applies to all exteriorlighting, regardless of its purpose (security, safety,aesthetics). Security lighting should be evaluated forits appropriateness in the context of the overall envi-ronment and surrounding community. Lighting forcommercial, residential and transition areas in anurban setting may have very different requirements(lighting levels and luminance ratios) than lighting in arural or remote location where glare and light trespassissues may have increased importance.

Light trespass usually fits into one of two categories:

Adjacent property receives unwanted light (highilluminance levels)

Excessive brightness occurs in the normal field ofvision (nuisance glare)

Efforts have been made in numerous jurisdictions to

write ordinances or bylaws controlling light trespass.One method is based on using specific EnvironmentalZone descriptions that underlie any restrictions onoutdoor lighting. Areas may be classified into a seriesof Environmental Zones (E1 through E4) based uponthe extent to which control of light trespass is consid-ered necessary or desirable. These have been devel-oped by the International Commission on Illumination(CIE) and have been accepted by IESNA as suitablefor application in North America. The Zones aredefined by CIE as follows:

E1 Areas with intrinsically dark landscapes. Examplesare national parks, areas of outstanding naturalbeauty, or residential areas where inhabitantshave expressed a strong desire for strict limitationof light trespass.

E2 Areas of low ambient brightness. These may besuburban and rural residential areas. Roadwaysmay be lighted to typical residential standards.

E3 Areas of medium ambient brightness. These willgenerally be urban residential areas. Roadwaylighting will normally be to traffic route standards.

E4 Areas of high ambient brightness. Normally thiscategory will include dense urban areas withmixed residential and commercial use with a highlevel of nighttime activity.

Within any category a curfew of after hours time maybe established, allowing higher lighting levels duringthose hours when the curfew is not in effect.

There is no single set of values/limits that will work inevery situation. The following recommendations3 ** aresuggested illuminance limits to control light trespass.The values for the various zones are measured at avery specific location-at the property line on adjacentproperty and at the eye in a plane perpendicular to theline of sight. Illuminance values for security lightingneeds in Section 7.0 are measured in different planesand viewing angles and are not incompatible with thelight trespass limits when issues such as glare andcontrol of light distribution are addressed.

Zone and Recommended MaximumDescription IlluminanceZone E1 1 lux (0.1 fc)Intrinsically darkZone E2 3 lux (0.3 fc)Low ambient brightnessZone E3 8 lux (0.8 fc)Medium ambient brightnessZone E4 15 lux (1.5 fc)High ambient brightness

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** These recommendations are based on those in the Guide on the Limitation of theEffects of Obtrusive Light from Outdoor Lighting Installations. Report of CIE committeeTC5.12 - Obtrusive Light. Commission Internationale de lEclairage, CIE, Vienna, Austria

The challenge for the designer of security lighting sys-tems is to determine the appropriate solution not onlyfor the site to be lighted but also for the surroundingcommunity, especially when different jurisdictionsadopt different Environmental Zones.

3.3 Security Lighting PlanningTo achieve the objectives of security lighting, attentionmust be given to both vertical and horizontal illumi-nances, the uniformity of the illuminance distribution,the effect of obstructions, the reflectance of surfaces,background contrast, degree of glare, the spectralpower distribution of the light source, the interactionwith electronic surveillance systems, and the effect onthe surrounding area.

Lighting can be a deterrent to criminal acts. Properlyinstalled security lighting is cost effective, easy tooperate, and dependable. The extent and type oflighting to be used as part of a balanced security sys-tem will be determined by several different factors:

Criminal History - In the case of an existing site, it iscritical that security and lighting professionals consultdata that details prior criminal history on or near thepremises before changing the lighting or other securi-ty elements at the site. Generally, such an analysisshould be performed annually, and the security profileof the property and adjacent properties adjustedaccordingly. If the site is being developed in a previ-ously unoccupied area, or if there is a fundamentalchange in use, an analysis of crime in the surroundingarea is acceptable. If the site is in a high-crime area,many physical defenses, including lighting, will proba-bly be required to maintain overall security on thepremises. As success in controlling or reducing crimeis realized, it may be possible to reallocate valuableresources. Security is an issue for a property when ahistory of relevant crime exists. For more informationon the analysis of crime, see Annex C.

Nature of the Site - The type of facility or business, thehours of operation or access, and surrounding condi-tions affect the approach to security.

Degree of Obstruction - Landscape design, fencesand other obstructions, and building configurationsshould not retard detection and identification of unau-thorized persons on premises. Lighting should bedesigned to avoid deep shadows, be uniform, andpermit observation of the activities of those allowed onthe site.

Ambient Luminance of the Surrounding Area -Security elements at one site affect the security ele-ments on adjoining sites. It is acceptable practice torely on off-premises sources of ambient lighting when

planning security, provided that the ambient source isconsistent in quantity, quality, and performance.

Impact on Surrounding Area - Stray light from a secu-rity installation may be considered as light trespass byneighbors. Stray light or over-lighting may also haveeffects on safety on nearby roads and railroads.Where signal lights are used to control traffic onroads, railroads, rivers, or at sea, care should betaken to avoid confusion caused by disability glarefrom the security lighting system. Lighting can alsohave an environmental impact on nocturnal animals,migratory birds and nesting sea turtles. Local lightingordinances should be consulted prior to design workfor any limitations on mounting height, source type,wattage, shielding, and other local requirements thatmust be followed. Permission for variances should beobtained from the authority having jurisdiction.

4.0 UNDERSTANDING WHEN SECURITY IS ANISSUE

Designers, prevention professionals, managers, andowners should consider security an issue when oneor more of the following conditions exist:

1. The persons and/or property in the area to besecured present a desirable target to would-becriminals.

2. The property has a history of relevant crime orincreases in crime. (See Annex D.)

3. Crime in the surrounding area is high comparedto other political subdivisions, parts of the city, orcounty. (See Annex D.)

4. The results of a physical security survey or threatanalysis indicate a problem. (See Annex B.)

5. There are changing conditions, which exposepersons to new security hazards or increasedrisk.

6. Obvious physical signs of antisocial behaviornear or on the property such as graffiti, vagrants,broken windows, trash buildup, trespass, orpoorly maintained properties.

7. There are recurring, reasonable resident or cus-tomer complaints or concerns about security, orfear of crime.

8. High profile or troublesome areas exist such asbars, nightclubs, gambling halls, gang or teengathering spots.

9. There are industrial or commercial applicationswhere persons or property are prone to attack,such as ATM and night depositories, conve-nience stores, and railway yards.

10. Restricted access industrial or governmentinstallations are in the area.

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11. A time of national emergency such as war, actsof terrorism, and declared emergencies.

When it is determined that security is an issue, rea-sonable and necessary measures need to be taken toimprove security and safety conditions at the site inresponse to the potential threat. Each site will have itsown set of relative conditions, pressures, usage, andthreats. However, the following suggestions are aplace to start:

1. Are there mission and objective statementsregarding the security and safety of others, andare these up to date?

2. Are there adequate post orders (job descrip-tions) for those responsible for carrying outsecurity duties?

3. Are policies and procedures up-to-date, and dothese documents reflect the true needs of thesite?

4. Have tenants, and those that occupy or use thespace, been advised of the potential threat levelor the hazard?

5. Have public and private law enforcement agen-cies been notified of the condition, and did thisnotification include a request for assistance oradditional patrols?

6. Has a security survey or audit been performedor updated since the security is an issue deter-mination was made?

7. Do changes in procedures, staffing levels, andsecurity hardware need to be made?

8. Do illumination systems, levels, uniformityratios, glare control, and maintenance sched-ules meet recommended practices, standards,and code requirements?

If there is a history of violence or violent-prone attacksagainst persons, then it is likely that crimes of a simi-lar nature will occur in the future, given the same cir-cumstances. If a property has a history of incidentssuch as car thefts, gang graffiti, abandoned cars, van-dalism, or broken fences, lighting fixtures (luminaires)or windows, a reasonable person could conclude thatthe site is not secure, and the owners need to takeaction. Similarly, ongoing complaints from users of theproperty, changing conditions, or when a high-riskbusiness moves into the area, may indicate a threat toboth property and persons. The professional securityand/or lighting designer should take note of this, andplan accordingly.

When operations are conducted at night or duringinstances of poor visibility, the quantity and quality ofthe lighting may need to be increased to aid in the pro-tection of persons and property. Conversely, if condi-tions improve, it is reasonable to reduce the level of

security, to a point equal to the perceived threat. Insuch cases, a test phase should be conducted andevaluated with defined achievement goals. A test peri-od of six months should be considered, with monthlyevaluation increments for comparison.

Good lighting alone cannot guarantee security. Goodsecurity lighting, when integrated into a balancedsecurity plan, will, however, play a critical role inreducing or displacing crime and make the othersecurity elements more effective.

5.0 VISIBILITY CONCERNS IN SECURITYAPPLICATIONS

It is mostly at night that the highest fear of crimeoccurs. Sometimes common sense or intuitionenables good decision making; other times the physi-cal senses alert one to danger. Although all of thesenses provide information about the environment, it isthrough vision that the majority of information isacquired and processed by the brain. Vision, therefore,has a tremendous impact on the decision makingprocess.

Lighting facilitates visual perception of a space andarea around the observer, and the observers ability tosee. For security purposes, the important lighting cri-teria are illuminance, uniformity, glare and shadows.Refer to Table 1 for the relative importance of theseand other quality factors for specific applications.

5.1 Illuminance

Illuminance is the density of light that impinges (fallson) a surface. Illuminance, or quantity of light valuesare provided for a variety of applications in Section7.2. Measurements are made using an illuminancemeter (often referred to as a light or footcandle meter).The primary unit of measurement for illuminance is lux(metric) or footcandle (US-English).

The two primary planes for measuring illuminance arehorizontal and vertical. As a general rule, values notspecifically labeled as vertical, are assumed to behorizontal lux (footcandles). (A summary of illumi-nance values for specific applications in Section 7.2can be found in Table 1.) Note that for security light-ing, vertical illuminance is often more important thanhorizontal because of the need to identify people.

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5.2 Horizontal Illuminance

The density of luminous flux on a horizontal surface isreferred to as horizontal illuminance. Most illuminancemeasurements or discussions about security lightingrefer to horizontal values. These readings are record-ed with the light meter held in a horizontal plane orplaced on a horizontal surface, such as the pavementin parking lots, grounds, on roofs of buildings, or table-tops. Unless otherwise stated, horizontal illuminanceis measured at grade. Note that many manmade sur-faces such as roads, parking lots, or landscapedareas are not exactly level and may contain deliberategrades for drainage. As a practical matter, these areconsidered horizontal, unless the grade is steep. Formore information on vertical and horizontal illumi-nance, and taking measurements, refer to Annex B.

5.3 Vertical Illuminance

Vertical illuminance is important for identification ofpeople. There should be sufficient light to positivelyidentify a face and read body language as either famil-iar, unfamiliar, or threatening at a distance of at least9 m (30 ft) from the viewer. Unless otherwise noted,vertical illuminance is measured at 1.5 m (5 ft) abovegrade. (See Annex B.)

Lighting that allows identification of faces is a relativelynew concept in security lighting, but important in certainapplications, such as parking facilities, peep-hole view-ing, or at security checkpoints. If the luminance of thebackground (behind the face) is more than four timesthe luminance on the face, the image will be in silhou-ette. As a practical matter, in an empty parking lot thebackground may be the pavement at a considerabledistance away with luminances less than those neces-sary to cause the face to go into silhouette. However,areas with vertical surfaces immediately adjacent to theperson being viewed, such as a light colored wallbehind the customer at a drive-up window, could easilyproduce luminances exceeding the recommendedluminance ratio of 4:1 (background-to-face).

5.4 Uniformity

Uniformity refers to the evenness of the distribution oflight on the surface(s). In determining uniformity, min-imum, average, and maximum illuminances are com-pared using ratios; either average-to-minimum ormaximum-to-minimum. Uniformity in security lightingaids security perception, while reducing the necessityfor eye adjustment when scanning or using the area.Uniformity ratios (average illuminance divided by min-imum illuminance) vary depending upon the applica-tion. (See Section 7.2.)

5.5 Glare

Glare is the sensation produced by luminances (with-in the visual field) that are sufficiently greater than theluminance to which the eyes are adapted. Glare caus-es annoyance, discomfort, or loss in visual perfor-mance or visibility, and usually reduces the benefits ofsecurity lighting. There are two types of glare, disabil-ity glare and discomfort glare. Disability glare is theeffect of stray light in the eye whereby visibility andvisual performance are reduced. It can often be attrib-uted to poorly shielded or non-cutoff luminaires.Discomfort glare produces discomfort but may notinterfere with visual performance or visibility.Overhead glare is manifested by reflections off eye-glasses, eyelashes, cheekbones and other reflectiveareas around the eye. Direct glare results from highluminances or insufficiently shielded light sources inthe field of view. Reflected glare is caused by a highluminance image on a specular or glossy surface,causing detail to be partially or totally obscured.Perimeter glare, however, when oriented to the out-side of the site, may be desirable and useful in somesecure sites to make the inside area less definable towould-be trespassers.

5.6 Shadows

Shadows reduce the effectiveness and impair securitylighting. When shadows are sharply defined at or nearan area, they may be annoying and discourage a feel-ing of safety. In addition, shadows make it difficult forusers of property and equipment to maintain qualitysurveillance. Shadows reduce uniformity of lighting.

5.7 Establishing Site Divisions

When planning or evaluating security lighting, design-ers will find it helpful to divide a facility into sectionssuch as total site, pedestrian, pedestrian path, build-ing, and perimeter zones. Each may require consid-eration of a differing set of perception factors.

5.8 Total Site Zone

Large sites, with a need to provide protection for per-sons and property, are lighted most economicallywith high-wattage, high-mounted luminaires, spacedto provide uniform illuminance. (See Figure 1.)Mounting height limitations and other restrictionsimposed by local ordinances may dictate morenumerous luminaire locations to achieve adequateuniformity. Two other important issues that must beaddressed are light trespass and light pollution(obtrusive light). Luminaires with cutoff or semi-cutoffdistributions can provide adequate vertical illumi-nance and be good neighbors for most applications.

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(See Section 6.0, item 9 and Figure 11.) The typicalmounting heights for luminaires in the total site zoneare 9 to 18 m (30 to 60 ft). Each pole may have oneor more luminaires usually housing 250 W to 1000 Whigh intensity discharge (HID) lamps. A selection oflight distribution patterns are available that lendthemselves to a variety of parking lot, walkway andsite geometries, with the outward appearance of theluminaire housing remaining consistent. Well-designed glare-control louvers or visors can be usedto reduce pedestrian glare, while allowing the flood-light to perform as intended.

5.9 Pedestrian Zone

Pedestrian areas require increased visibility and dif-ferent quality considerations than the site zone.Luminaires for mounting heights lower than thoseused for site lighting produce wider beam characteris-tics than equipment designed for high mountingheights. The use of full cutoff luminaires, however, atlow mounting heights in this zone will not provide highvertical illuminance levels. The typical mountingheight for the pedestrian zone is in the 3 to 6 m (10 to20 ft) range. Note that if floodlights are installed andaimed at high angles from vertical in areas adjacent topedestrian zones, such as for building faade lighting,they may produce direct glare and light trespass if thelight shines through the pedestrian zone.

5.10 Pedestrian Path Zone

Paths require luminaires on a pedestrian scale, delin-eating the walking area and connecting the site withthe structure. The path zone defines the traffic pat-terns and establishes a sense of welcome and secu-rity, particularly important for facilities with 24-houroperations. Bollards or landscape-style luminaires areoften used to delineate paths and to provide highlight-ing without visual obstruction. The typical mountingheight for bollards housing lamps from 50 to 100 wattsis 60 to 105 cm (24 to 42 inches). Spacing and mount-ing height depends on the lamp type and photometricdistribution, according to manufacturers recommen-dations. Note that this type of low-level luminaire oftenproduces little or no facial illumination, and should beused only to supplement pole-mounted luminaires ona pedestrian scale at 2.4 to 3 m (8 to 10 ft).

5.11 Building Zone

Building floodlighting can be employed as a securitylighting technique, creating large areas of vertical illu-minance and adding to the ambiance of the area bymeans of light reflected off the building surface.Luminaire setback position from the building facadeshould be three-fourths the height of the building foruniform lighting; the spacing should not exceed twicethe setback. The ground-mounted aiming point shouldbe at least two-thirds up the building height. If the set-back is reduced, the aiming point must go higher. (SeeFigures 2 (a) and 2 (b).) Local ordinances should be

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Figure 1. High-mounted luminaires provideuniform illuminance for approach driveway,sidewalks and parking areas in this com-plex. (Photo courtesy of Holophane.)

consulted to determine if this lighting technique is per-missible. Care must be taken to avoid producing glareto the users of the area, light impinging on pedestrianzones, and over-lighting. Careful control of the lightoutput is essential to avoid wasted light and energy, aswell as creating adverse effects of sky glow.

5.12 Building Perimeter Zone

Wall mounted luminaires are often used to provide illu-mination for walkways, entrances, and underpasses.Luminaire manufacturers data provide recommendedspacing to mounting height ratios.

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Figure 2 (a). Ideal geometry for uniform floodlight-ing where the total angular coverage to the flood-light locations is greater than 90 degrees and thebuilding height is greater than two setback dis-tances (but does not exceed six setback distances).

Figure 2 (b). An explanation of NEMA field angle classifications and their effective projection distances arewidely used by the lighting industry to classify the overall candela distribution patterns of floodlights.

6.0 LIGHTING EQUIPMENT

Selecting and applying the proper lighting equipmentcan make the difference between a security lightinginstallation that deters crime and one that actually aidscriminals. Careful selection and appropriate placementof equipment will insure that required light levels areachieved with limited glare and reliable operation. Awell-designed lighting system will make the spaceattractive during the day and attractive at night. (SeeFigure 3.) It is important, however, not to judge deco-rative luminaires solely on their daytime appearance.Of greater significance are nighttime performanceissues such as light distribution, and control of glareand light trespass.

Considerations affecting an installation include:

1. Light Source Color - For the purposes of securitylighting, color rendition is an important considerationin the choice of light sources used. There are severalimportant measurements of color, including ColorRendering Index, Color Temperature, and SpectralPower Distribution.

a. Color Rendering Index - How do things appearunder a light source? Do colors look the same at nightas they do during the day? Is it important to be able todescribe the color of a potential suspects clothes? Orthe color of an automobile involved in a hit-skip acci-dent? Color Rendering Index (CRI) is a method usedfor measuring and specifying color rendering proper-ties of light sources. It measures the degree of colorshift objects undergo when illuminated by a particularlight source as compared with the same objects whenlighted by a reference source of comparable colortemperature. CRI is 100 or less. The higher the CRI,the better the color rendering ability of the source.Research has shown that almost any nominally whitelight source (CRI of 50 or higher) allows accurate andconfident color identification at the illuminances usedin public spaces at night. High-pressure sodium lampsallow accurate but less confident color naming at highilluminances used for public spaces, but both accura-cy and confidence declines at lower illuminances.Low-pressure sodium lamps do not allow accuratecolor identification under any illuminance level.

b. Color Temperature - Light sources are oftendescribed as warm or cool in appearance. The des-ignation of a lamps color temperature (or correlatedcolor temperature (CCT)) can be thought of as heatinga piece of metal, which causes the color of the metal tochange, until the color of the metal and the lamp arealmost the same. The temperature of the metal is

recorded (in Kelvin) and that number is used todescribe the lamps color. Warm sources like incandes-cent, high-pressure sodium, and warm white fluores-cent lamps have color temperatures between 1800Kand 3200K. Cool sources like mercury vapor, metalhalide, and cool white fluorescent lamps have colortemperatures between 4000K and 7500K. (See Figure4, color insert.)

c. Spectral Power Distribution - The composition oflight can be described by its spectral power distribu-tion (SPD), which shows the relative amounts ofpower at wavelengths of different colors. The visiblewavelength range extends from about 380 to 780nanometers. (See Figure 5, color insert..) When alight source contains energy throughout the visiblespectrum, it is seen as emitting white light. Also,when the primary colors (monochromatic red, greenand blue wavelengths) are combined, the resultappears as white light. Many electric light sources,however, produce light that is generally unequal invarious parts of the visual response range, whichaffects the way objects appear. If a light source isweak in red wavelength output, materials normallyinterpreted as red during the daytime may be mutedor appear dull under the source at night. The SPDs ofvarious lamps can be obtained from lamp manufac-

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Figure 3. Pole-mounted lantern-style luminaires helpcreate a turn-of-the-century theme for this street,which is home to numerous upscale businesses andstores. They are equally attractive during the day ornight. Care should always be exercised in choosingdecorative luminaires, which may produce glare andlight trespass. (Photo courtesy of OSRAM SYLVANIA.)

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Figure 6. Color temperature, Color Rendering Index and Spectral Power Distribution Effects of Various Sources.

turers. The SPD looks like a graph with bars (or a con-tinuous line) from the blue to the red end of the spec-trum. Peaks in the SPD represent strong energy out-put from the lamp in that area, while valleys in theSPD indicate the lamps weakness to illuminate cer-tain colors.

Figure 6 shows several different light sources com-monly used for safety and security lighting.Depending on the needs of the application, the chartcan be used as a guide for lamp type selection, but isnot intended to be a comprehensive list of all lightsources. Light source manufacturers data should beconsulted for more specific and comprehensive infor-mation.

2. Poles: In general, the taller the poles, the fewerpoles will be required for a given area, resulting inimproved uniformity and less likelihood of vandalismto the luminaires. In many localities, however, poleheight is restricted. When lower mounting heights areused, more poles and lower luminaire wattages willlikely be required to maintain adequate uniformity andto avoid over-lighting. (See Figure 7.)

3. Controls: Many existing lighting ordinances requirethat lighting in certain areas or for certain lightingapplications be extinguished at a particular hour.Establishment of curfews is a logical method to pro-vide partial control of light trespass. However, whenconsidering application of a curfew, the needs of safe-ty and security must first be evaluated to determinehow, when or if curfews should be relaxed or modifiedin the Environmental Zone (Section 3.0) or Site Zone(Section 5.0).

For non-residential applications, security lighting unitsshould always be controlled automatically with photo-cells, timers, or other sensors; and not assigned to anindividual user, except perhaps in a guardhouse appli-

cation where light is needed only occasionally forundercarriage or periodic inspections. Types of con-trols include time switches, photocells, dimmers andmotion detectors. These may be used individually orin combination to control a single luminaire or a groupof luminaires.

a. Time Switch - Generally used when a definedon/off cycle is required without regard for whether ornot the light is actually necessary when energized.Unless used in conjunction with a photocell, theadverse impacts on energy consumption should beconsidered. Time switches or clocks that can be pro-grammed to adjust on/off times with the seasons andto energize dimmers during low traffic periods shouldbe selected. Time switches are not effective whereheavy weather causes darkness/reduced visibilityduring daylight hours. AC power time switches oper-ated on commercial power should have an AC or DCbackup to respond to primary power disruption.

b. Photocells - Used to control an individual luminaireor a series of luminaires when operated in combina-tion with a contactor. Photocells can also automatical-ly energize luminaires during dark periods, regardlessof time of day. When photocells are combined with atime switch, they can be used to energize lights atdusk and then de-energize them at a specified timewhen the lighting is no longer required; e.g., after busi-ness hours. The photocells should be placed wherethey will sense the darkest scene and where they arenot influenced by the light output of the luminaire(s)they are controlling. When security is an issue, photo-cells should be located where a flashlight, or otherextraneous light cannot defeat them.

c. Dimmers - Used to reduce illumination (and power)during low traffic periods in such areas as industrialemployee parking lots during working hours, or latenight mall parking, when no one should be in the area.By dimming all units, the entire area remains uniform-ly illuminated, compared to the uneven lightedappearance that occurs when half of the units are de-energized to save electricity. Dimmable fluorescentand HID units require special ballasts.

d. Motion Detectors - Used to energize specific or allunits when motion is detected. Motion detectors shouldonly be used with incandescent and fluorescentsources because of the slow start up of HID sources,unless the luminaires are dual-level HID types. Motiondetectors can be effective in introducing an element ofsurprise. These devices can activate a strong lightbeam toward a potential intruder, who senses detec-tion, while at the same time alerting off-site personnel.Motion detectors are especially effective in residentialapplications and when used in pairs in traps. A motion

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Figure 7. A typical family of luminaires exemplifyingvarious pole heights and luminaire configurations.(Illustration courtesy of Clanton and Associates, Inc.)

detector trap is used in confined areas, such as spacesbetween buildings, or fences and buildings. The firstmotion detector is left exposed to the eye, and the sec-ond detector is disguised and aimed to respond to theblind spots of the first detector.

4. Maintenance: No security lighting system canremain effective without regularly scheduled mainte-nance. A planned maintenance program should includeimmediate replacement of failed lamps, electrical com-ponents, photocells, and vandalized or damaged lumi-naires, and involve regular cleaning of luminaires andshrubbery pruning. Inspections of all lamps should beperformed at least monthly during hours of darkness tolook for dirty or broken lenses, failed lamps or those notperforming to specified standards, tree limbs blockinglight paths, and for evidence of vandalism. In the caseof large properties where there are on-site securitypatrols or maintenance personnel, lamps should bechecked nightly, and observed outages reported inpatrol logs or maintenance request records.

5. Lamp replacement: A well-designed systemshould have overlapping light patterns so that no areais dependent on a single luminaire. Failed lamps,however, should be replaced immediately, in case asecond lamp in the same area also fails. When instal-lations require special lift equipment to service theluminaires, consideration should be given to replacingall of the lamps in the luminaire(s) on the pole at thesame time to avoid extra labor costs. To prevent prob-lems, lamps should be replaced at or before the man-ufacturers published rated life data for that lamp.

6. Cleaning: Regardless of the quality of the equip-ment, insects and dirt will collect in enclosed luminaires;therefore, all units should be cleaned at least at the timeof lamp replacement. When security is an issue, clean-ing may be required more frequently to maintain equip-ment within the most effective operating tolerances.

7. Pruning: Trees and shrubbery that would other-wise block light output from security luminaires mustbe pruned at least annually to prevent interferencewith the light distribution pattern and eliminate shad-owy areas where wrongdoers can hide. Where prac-tical, low branches and bushes should be trimmed toreduce hiding places and improve sight lines. (SeeFigure 8.)

8. Design Considerations: In many situations, lumi-naires used for security lighting will be part of the gen-eral lighting system, as in parking facilities or for build-ing enhancement. Frequently, the daytime appear-ance of the luminaire and pole is a deciding factor inthe choice of equipment, with quality and functionalitybeing of lesser importance. For example, a shopping

mall may choose more expensive equipment in pub-lic parking areas and lower cost units in employeeareas. It is important to consider that employees willusually arrive earlier and depart later, when few cus-tomers are present and may, therefore, be subject toa greater security risk.

Any outdoor luminaire can be utilized for security light-ing. Figure 9 shows a small sampling of various typesof outdoor lighting equipment. All devices must beproperly installed and maintained; and, if exposed toweather, must be approved for and labeled for wetlocations by an independent or certified laboratory.

The distribution and degree of cutoff provided by theluminaire is a critical consideration in new and upgrad-ed projects. (See Section 8 Glossary of Terms.)Considerations include:

a. Distribution ranging from Type I (narrow),through II, III, IV (increasing width), to Type V(symmetrical round or square). Some haveadditional performance descriptions such asforward throw, where limited light is projectedbehind the pole. The selection of the distribu-

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Figure 8. Luminaire must be selected to assure thatlight distribution will not be obstructed by thefoliage as the tree matures. Example shows pruningguide for street lighting.

tion type should be determined by a lightingprofessional based on the size, shape, andlocation to be illuminated. Several types mayfrequently be used on the same project; forexample, Type V used in the center and for-ward throws around the perimeter. (See Figure10.)

b. Degree of cutoff limits the percentage oftotal light output emitted above 90 (horizontal)and allowable high angle brightness. (SeeFigure 11.) It is outside the scope of this docu-ment to recommend the degree of cutoff. Whilethe requirements of the limits are very specific,the actual differences may be very subtle.Photometric tests should be utilized to deter-mine whether actual differences are significant.

7.0 SECURITY LIGHTING FOR CONTROLLEDSPACES

7.1 GeneralThe first question regarding controlled spaces iswhether to light the space at all. Lighting a securearea advertises the presence of something worthattacking and, hence, may attract criminals. In someapplications, keeping the area dark may be a bettersecurity approach. Examples of applications not tolight might include pumping stations in isolated farmcountry, or isolated telephone relay enclosures.However, if criminals are likely to know that the areacontains valuable materials, the absence of lightingmay make the target more difficult to defend. Thus,the decision to install a security lighting systemdepends on an understanding of the risk of criminal

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Figure 9. Typical luminaires and motion detector devices for residential and commercial applications. (Photoscourtesy of Hubbell Lighting and Ruud Lighting.)

General Purpose FloodlightsApplications: Parkingareas, recreation, facadelightingSources: Incandescent,Fluore-scent, HPS, MetalHalideDistributions: NEMA types1-7. Note: Rectangular unitshave Horizontal X Verticaldesignations. 3X6 etc.Mounting: Poles, structures,groundControls: Time clocks, photo-cells, motion detectors(incandescent only)

Landscape LuminairesApplications: Residential, small commercial Sources: Incandescent, fluorescent, metal-halide, mercury, HPSDistribution: Floodlight and Type VMounting: Ground, trees, structures Controls: Time clocks, photo-cells, motiondetectors (incandescent only)

Figure 9d

Architectural LuminairesApplications: Roadways,Parking lots, Walkways, etc.where daytime appearanceand/or light pollution andtrespass are important.Sources: HPS, MetalHalide- 70-400 wattsDistribution: Roadwaytypes I to V, forward throw.Mounting: Structures andpoles 15 or higher withdecorative armsControls: Time clocks,photo-cells

Roadway LuminairesApplications: Streets, drive-ways, parking areasSources: Metal-halide. HPS Distributions: Roadway typesI thru V. Cut-off units reduceglare and light pollutionMounting: Poles 20' andhigher with armsControls: Time clocks,photo-cells

Figure 9b

Refractor

Cutoff

Figure 9a

Figure 9c

activity. If the risk of criminal activity is low, and the tar-get relatively unknown to persons not familiar with thesite, then providing security lighting may be counter-productive, especially in rural, isolated, or otherwisedark areas. The risk of criminal attack is not the onlyconcern for the designer. Lighting for safety and theprotection of persons are always of vital importance.

Security lighting for a controlled area should provideuniform illumination so that anyone moving in oraround can be easily seen. The security lightingdesign should also provide sufficient illumination sothat intrusion or attempted intrusion into the area canbe detected, and any electronic surveillance devicessuch as security cameras can operate within recom-mended tolerances.

These objectives can be achieved in different waysdepending on the site and the nature of the securitysystem. Section 7.2 provides examples of securitylighting for some common controlled sites.

7.2 Specific ApplicationsThe recommended illuminances for each of the appli-cations described in this section are horizontal. Notethat vertical illuminance should be provided in allcases where there is a need to identify people (faceand body language) at a distance of at least 9 m (30ft) from the viewer. (See Section 5.3.) Typical recom-mended vertical illuminance values are 5 to 8 lux (0.5to 0.8 fc) or values that produce a uniformity ratio ofno more than 4:1, average to minimum between theluminances of the background and the face. (Thehigher the background luminance, the higher the ver-tical luminance to maintain the 4:1 ratio to prevent sil-houetting.) Variations from these recommended val-ues for a particular application are specifically noted.A lighting system that provides illumination from morethan one direction is recommended to achieve thegoal of facilitating facial identification and minimizingshadows or a silhouette effect as the person movesthrough a space. For guidance on measuring verticalilluminance see Annex B.

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Motion DetectorsApplications: Residential,commercialSources: Incandescent andfluorescentMounting: Structures withclear view of area to be lighted

Figure 9h

Surface Mounted LuminairesApplications: Perimeterareas near structures, entry-ways, walkways, parkingareas.Sources: Incandescent, fluo-rescent, HPS, Metal HalideDistributions: Ceiling Mtd.-TypeV, Wall Mtd. Wide-later-alControls: Time clocks,photo-cells, motion detectors(incandescent only)

Post-top LuminaireA wide varioety of styles in clear and coloredenclosuresApplications: Walkways, residential parkingareas where lower lighting levels are satisfactorySources: Incandescent, fluorescent, metal-halide, HPSDistribution: Symmetrical, most with uplight Mounting: Wall bracket, poles up to 15'Controls: Time clocks, photo-cells

General Purpose Luminaires

Applications: Small parking and rural areas. Cutoffunits reduce glare, light pollution and trespass.Sources: Mercury, HPS, Metal Halide-70-150 wattsDistribution: Roadway type VMounting: Structures and polesControls: Time clocks and photo-cells

Prismatic Cutoff

Figure 9g

Figure 9f

Figure 9e

7.2.1 Unoccupied Spaces

Storage Yards, Industrial and Equipment Areas, andContainer Terminals: Area lighting is typically accom-plished with floodlighting or luminaires mounted onpoles 9 m (30 ft) or more in height. The recommendedaverage illuminance on the surface of large openareas is 5 to 20 lux (0.5 to 2 fc) with an average-to-min-imum illuminance uniformity ratio not greater than 8:1.The greater the brightness of the surrounding area, thehigher the illuminance required to balance the bright-nesses in the space, while exercising caution to avoidlight trespass and glare. Luminaire spacing will dependon the output, mounting height, and distribution of theluminaires. In storage areas where unacceptablematerial losses have been sustained, or security is anissue, the average maintained illuminance levelsshould be at least 10 lux (1fc), with an average-to-min-imum uniformity ratio not greater than 6:1.

If the area contains a large number of obstructions tovisibility (as in container terminals or rail yards), a

design utilizing additional multiple source locationsand higher mounting heights will reduce shadows.(See Figure 12, color insert.) It will be helpful if theluminaires are positioned within the site, betweenobstructions, and with overlapping light patterns. Thereflectance of site materials can also be used toadvantage. Light, reflective colors on buildings and inconcrete paving will enhance the efficiency and uni-formity of the lighting system. (See Figure 13.)

While IESNA does not recommend designing lightingsystems with disability glare, the technique is some-times used in special security lighting applications toprotect a secure area. The glare renders would-beintruders outside the protected area highly visible toguards inside the perimeter, while masking the guardsand other features from the casual outside observer. Insuch a system, luminaires are mounted at or near eye

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Figure 11. Cutoff classifications

Figure 10. Light distribution patterns for seven different luminaire configurations used to providecoverage for roadways (Type III), parking lots (TypeIII and V) and pedestrian areas (Type II, III, and V)

level and aimed outward from the secure area. Typicalapplications of this principle include sensitive weaponsstorage facilities, prisons, and jails. This technique hasa high probability of producing light-trespass and lightpollution problems, and should be considered only inextreme cases, or those instances where facility secu-rity is a very high priority. In addition, it can only beeffective if the would-be intruders approach from theunprotected side, and when security personnel arepositioned on the inside of the installation.

7.2.2 Offices and Other Commercial Buildings

Building Exteriors: Primarypoints of entry to the buildingand the areas around theseentrances should be easily visi-ble and identifiable. Dependingon the construction of the build-ing, points of entry may includeunintended entry points, suchas through walls and roofs.Luminaires set in the ground,mounted on the building orunder the eaves, or mountedon poles, provide light for thesecritical areas. While ground-mounted floodlights may pro-vide uniform illuminance, theyare accessible and can bereadily neutralized. Pole-mounted luminaires are usuallythe best option for uniformly illu-minating the surfaces of thebuilding and the surroundingarea with less opportunity forvandalism. (See Figure 14.)The average recommendedvertical illuminance on thebuilding faade ranges from 5to 20 lux (0.5 to 2 fc) with a uni-formity ratio no greater than8:1or 6:1 depending on theacceptability of losses as dis-cussed above.Building Interiors: Securitylighting for the interiors of build-ings depends on the securitymethods available. If securityofficers are on site, or makefrequent checks of the location,it is appropriate to have contin-uous or controlled illuminationto allow for quick visual inspec-tions as officers make patrolrounds. The illumination of inte-

rior stairwells, hallways, and work areas should be con-sistent so officers are not subjected to changing pat-terns of light. Generally, interior lighting for patrol offi-cers in unoccupied buildings should be at least an aver-age of 10 lux (1fc) with an average-to-minimum unifor-mity ratio not greater than 6:1. Regardless of the illumi-nance provided, patrol officers should always carrysupplemental lighting devices such as flashlights, whenpatrolling inside enclosed structures. If the building ismonitored automatically using electronic devices,enough light should be provided to operate the equip-

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Figure 13. Container storage yard is uniformly lighted with good vertical illuminancebetween the containers. (Photo courtesy of General Electric Lighting Systems.)

Figure 14. A combination of pole mounted area lighting units, ground mountedfloodlights for building surfaces, roof mounted floodlights and an internallylighted glass wall faade provide a well-lighted building environment. (Photocourtesy of General Electric Lighting Systems.)

ment within recommended tolerances. If there areinfrared motion sensors or infrared cameras that do notrequire light, it is appropriate to design the system to bedark when secure and illuminated once trespass isdetected.

Perimeter Fences and Walls: The purpose of lightingperimeter walls and fences is to deter or slow trespassand to enable guards or surveillance equipment todetect intruders. Perimeter barriers have many differentforms, from masonry walls to barrier vegetation. Thetype of lighting used will depend on the objectives, theability to see through the barrier, neighborhood consid-erations, and whether one or both sides of the barrierare patrolled. (See Figure 15, color insert.) If bothsides of a solid barrier are under surveillance, lightingcan be provided by positioning luminaires over the topto reduce shadowed areas at the base of the barrier.

If a view through the barrier is possible, and if theobstruction is patrolled, it is useful to be able to seeboth sides. This can be accomplished with pole-mounted luminaires set back from the barrier. Thelighting will be most effective if the luminance of thefence on the patrolled side is lower than the luminanceof the area being viewed through the fence. This

objective can be achieved by using a low reflectancefence material such as black or dark green-coatedchain-link. If galvanized chain link is used, care shouldbe taken with the aiming of the luminaires to reducethe illuminance directly onto the fence.

Guarded Entrances and Gate Houses: Access tosecure areas is often controlled by security personnelwho stop and inspect people, identification documenta-tion, or vehicles. (See Figure 16.) The intensity of theinspections ranges from token checks or wavethroughto challenges and detailed searches, depending on theperceived threat. In the latter instance, the entrance orinspection point should be provided with multiple, redun-dant luminaires so that the loss of any one luminaire willnot seriously degrade the lighting available to the guardsto perform their tasks. For critical applications, backuppowered incandescent luminaires or non-interruptedsources should be employed during electrical outages.

Tasks include inspection of vehicles, vehicle licenseplates, personal identification, and vehicle contentsincluding the driver and other occupants. Good hori-zontal as well as vertical illuminance should be provid-ed to allow for easy facial identification, inspection ofcredentials, and packages, without the need for auxil-

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Figure 16. Guarded entrance with well lighted checkpoint.

Figure 17. Driveway approach and canopy at the guard house provide uniform light for checking vehicles.(Photo courtesy of Operational Support Services, Inc.)

iary hand-held devices such as flashlights. Inhigh security areas, some luminaires shouldbe mounted at or below pavement level tofacilitate inspection of the undersides of vehi-cles. Having a concrete or other reflectiveroad surface will increase the reflected lightand help in the inspection process. (SeeFigure 17.)

Illuminance at ground level for inspectionareas should be an average of 100 lux (10fc), or twice that of the immediate surround-ing areas, whichever is greater, and an aver-age-to-minimum uniformity ratio not greaterthan 3:1. In addition, vertical illuminanceequal to twenty five percent of the horizontalilluminance should be provided at the level of the dri-ver. Good color rendering light sources should also beused so that officers can easily discern the color ofclothing, documents, goods and vehicles.

Illuminance inside the guardhouse should be limited tothe minimum required for comfortable completion ofassigned tasks, such as report writing and equipmentuse. It should be possible to dim the illuminance in theguardhouse to allow the guard to see clearly throughthe windows at night and to limit the ability of thoseapproaching the gatehouse to see the guard. (SeeFigure 18.) Well-shielded task luminaires are essentialto avoid reflections on surveillance monitors and thewindows of the gatehouse. Fitting the gatehouse withspecular-reflecting; low-transmission glass at a tiltedangle, painting the inside of the gatehouse in dark col-ors, and ensuring that illumination can be dimmed, willall help limit the view into the gatehouse. For a cut-away view of how these ideas can be integrated intothe design of a guard station. (See Figure 19.)

In installations where entrances are monitored byClosed Circuit Television (CCTV) or electronic devices,illuminance at the checkpoint may be lower than thatat sites manned by security staff. Illuminance, howev-er, should be at levels consistent with the surveillanceequipment manufacturers recommendations.

7.2.3 Automated Teller Machines and NightDepositories

Background: Automated Teller Machines (ATM) areinstalled for customer convenience. In manyinstances, convenience and marketability overrideother factors with regard to site selection and place-ment. As a result, crime against ATM customers hasbecome a major concern for security professionals.The financial industry, and some local, state andprovincial jurisdictions have responded with recom-mendations, standards and ordinances to make after-

hours banking safer and more secure.4, 5 Night depos-itories (ND) are usually located at a banking facility andpose a somewhat different threat than ATMs in thatcash is brought to the facility rather than withdrawn;however the same security lighting techniques shouldbe applied.

There are three essential elements for after-hoursbanking facilities. These are known as the Three Ls:Location, Lighting and Landscaping.4

Location: There are three general types of locationsfor ATMs: Drive-up, Walk-up and Interior. These maybe either attached to a banking facility or free stand-ing. Except during normal banking hours, there areusually no trained attendants at any of these loca-tions. In all cases security is an issue.

Drive-up configurations allow the customer to remainin the vehicle where, in theory, they are surrounded bya protective barrier with a ready means of escape.Problems arise when the customers attention is on

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Figure 19. Tilted glass limits view of the interior ofthe guardhouse.

Figure 18. A well-balanced lighting system betweenthe interior of the guardhouse and the exterior sur-veillance lighting. (Photos courtesy of OperationalSupport Services, Inc.)

the machine, allowing a perpetrator to enter the vehi-cle on the passenger side from an adjacent hidingplace. Shrubbery and other possible areas of con-cealment should be eliminated close to the ATM andsigns should suggest that customers lock car doors.

Walk-up locations create the greatest danger, as thecustomer is defenseless. No shrubbery should belocated in the immediate area and lighting should begraduated to allow the customers eyes to adapt fromthe darker sidewalk to the brighter ATM and reducedas the customer leaves the area. (See Figure 20.)

Interior locations may be enclosed or free standing insuch areas as supermarkets, malls, transportation ter-minals and convenience stores. In many such areas,other people may be in the immediate vicinity; how-ever, they are not usually paying attention to ATM cus-tomers. Some locations are self-enclosed, which pro-vides privacy for the customer and a view of the sur-rounding area. Some jurisdictions require that abankcard be used for access, allowing only one cus-tomer at a time. If the ATM is not enclosed, the spacesurrounding it should be clear and defined to discour-age non-customers from close contact. Illuminancevalues should be higher than surrounding areas toallow identification of potential wrong-doers.

Normal Practice and Standards: Some jurisdictionshave enacted ordinances that specify minimum secu-rity lighting for ATMs and NDs and frequently establishlimits for shrubbery or other obstructions. These ordi-nances emphasize the importance of security lightingin helping to deter crime against customers. Designersshould consult local authorities and use these require-ments as minimum only, because higher luminance insurrounding areas may necessitate more lighting inthe ATM area.Designers and bank security officers should considerthe following guidelines:

(Note: Unless otherwise specified, all distancesand illuminance values are minimum and shouldbe adjusted for local conditions.)

To assist the customer in operating the ATM, theface of the machine should have 150 lux (15 fc), with100 lux (10 fc) on all horizontal surfaces within 3.5meters (10 ft) of the face of the ATM. An averagehorizontal illuminance of 20 lux (2 fc) should be pro-vided within a 15.2 m (50 ft) radius of exterior units.

Supporting parking spaces within 18.5 m (60 ft) ofthe ATM, should have an average of 20 lux (2 fc).

When the ATM is within 3 m (10 ft) of the corner ofthe building, illuminance of 20 lux (2 fc), shouldextend 12.2 m (40 ft) down the side of the building

Installation of lighting units should be redundant tothe extent that one failed unit will not reduce the

illuminance below the above minimums. Average-to-minimum uniformity ratio should not

exceed 3:1 for each of the zones described above. Lighting should not produce glare for the users,

pedestrians, drivers and/or light trespass ontoneighboring properties.

Illuminance at the machine and surrounding areasshould provide excellent definition of facial identifica-tion (vertical illuminance) at a distance of 9 m (30 ft).

Illuminance levels should support all CCTV operat-ing requirements.

Customers should have an unobstructed view fromthe face of the unit to a distance of 15.2 m (50 ft),in all approachable directions. If necessary, thisrequirement can be augmented by other devicessuch as mirrors, CCTV, fencing and barriers.

Potential hiding places should be eliminated withinthe measured area.

Luminaires should be tamper proof and/or wet-labeled where necessary.

To insure good maintenance practice, it is essentialthat all lighting sources be checked at frequentintervals. Nonfunctioning equipment can createlife-threatening consequences. Personnel who pro-vide cash service to the ATM should check thelighting system and report any outages to the main-tenance department.

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Figure 20. Recessed luminaires in the roof overhangprovide uniform lighting on the walkway and verticalilluminance for customer transactions at the machine.(Photo courtesy of Ruud Lighting.)

7.2.4 Parking Facilities (Lots and Garages)

Techniques for lighting parking lots and garages aredescribed in IESNA RP-20-98, Lighting for ParkingFacilities.5 Walkways are discussed in IESNA DG-5-94,Lighting for Walkways and Class 1 Bikeways.6 Whensecurity is an issue, the recommended security illumi-nance for open parking facilities should be an averageof 30 lux (3 fc) on the pavement. A uniformity ratio notgreater than 4:1, average-to-minimum should be main-tained. Attention should be given to the use of the facili-ty and hours of operation. Uniform lighting for an emptylot is of little value, but when space is used to capacity itis important to achieve the desired lighting levelbetween vehicles since these are the likely places forcrime to occur. Sidewalks, footpaths, and groundsaround or supporting open parking lots should be illumi-nated to an average of 60 lux (6 fc), with an average-to-minimum uniformity ratio not greater than 4:1. (SeeFigure 21.)

Garages and Covered Parking Spaces

The security threat to unescorted people and unse-cured property in covered parking garages can be high.Isolated floors, numerous places to hide, lack of effec-tive surveillance, and limited escape routes often com-

bine to create this condition. (See Figure 22, colorinsert.) When security is an issue, in parking garagesand covered parking facilities, the recommended aver-age illuminance should be 60 lux (6 fc) on the pave-ment, with an average-to-minimum uniformity ratio notgreater than 4:1. These illuminances should be main-tained whenever access is allowed to the parkingareas. Glare should be avoided in such installations.Back-up generators or battery-operated lighting arenecessary in parking areas, stairwells, elevators, andexit ramps when the public is allowed access. Whensecurity is an issue, at locations where people gather,such as at elevators and stairs, illuminance should bean average of 100 lux (10 fc) in a 9 m (30 ft) radius fromthe center of the gathering point with an average-to-minimum uniformity ratio not greater than 4:1.

Perimeter or boundary lighting should allow detectionof those who loiter outside the site and those who areentering or exiting the site. Interior lighting shouldallow safe movement and easy detection of hazardsand threats out to a distance of at least 9 m (30 ft).(See Figure 23 (a) and (b).)

Visual adaptation occurs when going between regionsof high and low light levels, such as from a parkingstructure into the street or vice versa. Transitionallighting helps the eyes to adapt. For example, duringthe daytime the lighting levels at the threshold of thestructure might be increased and reduced at theentrance during nighttime use. The use of electronicsensors provides an effective solution to adjusting theentry and interior illumination when transitioning fromday to night. The quality of the light should be uniformto avoid shadows and glare.

Retro-reflective material should be used for wall signs,common walkways, gathering points, and hazardousareas. Location signs (level and bay) on columns thatface the aisles are useful indicators. Letter, numberand color patterns should indicate floor locations. Thebackground of such signs should be the floor color.Candy striped columns, black and yellow, are usefulto highlight drive paths. All of these safety features willhelp pedestrians to locate exits and their vehiclesmore quickly, reduce exposure to criminal hazards,and encourage a feeling of well being and self control.

7.2.5 Residential Parking Areas

Common use parking structures or open parkingareas should be lighted according to IESNA RP-20-98, Lighting for Parking Facilities6 and when securityis an issue to Section 7.2.4 of this document.

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Figure 21. Cut off luminaires in an employee parkinglot provide uniform illumination for workers leavingafter normal business hours and excellent surveil-lance opportunities for observers from an upper floorin the building. (Photo courtesy of Ruud Lighting.)

7.2.6 Parking Lots and Areas for Public ParksWhere security is an issue in parks and public spaces,the recommended average maintained horizontal illu-minance for open parking facilities in or adjacent toparks should be no less than 30 lux (3 fc) on the pave-ment with an average-to-minimum uniformity ratio notgreater than 4:1. (See Figure 24.)

Parks and public areas by their very natu