June 2007, Vol. 3, No. 2

Vol. 3 No. 2 IEEE PSES Product Safety Engineering Newsletter

TheProductSafetyEngineeringNewsletter

Vol. 3, No. 2 June 2007

President’s Message

What’s InsidePresident’s Message..........................1

Officers of the IEEE PSES................2

Chapter Activities....................................4

Technicially Speaking.......................... 6

Effect of Thin Solid Insulating Material .. 15

News and Notes...............................22

2007 CSA/RIA Robot Safety Conference Re-port ..........................18

eDJ: See next Issue ....................

Continued on Page 3

Henry Benitez

Message from the President:

Hello Product Safety Engineering SocietyMembers,

We thank our members who have submittedarticles to the PSES newsletter and for thevolunteers that have diligently been puttingnewsletter together. We take pride in providinga high quality newsletter to you the membersby you the members. Please provide feedbackboth positive and negative on what you think.Also consider submitting technical articles inyour areas of expertise for publication.

The Product Safety Engineering Societycontinues to grow. Overall IEEE membershipis growing slightly with membership greaterthan 300,000. There is some discussion ofmore aggressive membership growth of up to500,000 people in the next 5–10 years.

PSES is integrating with the other 40 or soIEEE Societies and Councils at the TechnicalActivities Board level. The PSES Board ofDirectors has become more familiar with IEEEprocess and expectations. We are excitedabout expanding the breadth of our PSES-sponsored conferences. We plan to sponsorconferences outside the United States incoming years. This year’s conference is in

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ProductSafetyEngineeringNewsletter

The Product Safety Engineering Newsletter is published by the IEEE Product Safety EngineeringSociety. No part of this newsletter may be reproduced without written permission of the authors. Allrights to the article remain with the authors.

Opinions expressed in this newsletter are those of the authors and do not necessarily represent theopinions of the Society or any of its members. Indeed, there may be and often are substantialdisagreements with some of the opinions expressed by the authors.

Copyright 2006 IEEE Product Safety Engineering Society.

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Executive Committee Name TermPresident Henry Benitez (06-07)Past President Mark Montrose (06-07)President Elect Jim Bacher (07)Secretary Daniece Carpenter (07-08)Treasurer Murlin Marks (07-08)Vice President - Communications Dan Roman (07-08)Vice President - Member Services Ken Thomas (07-08)Vice President - Technical Activities Jack Burns (07-08)Vice President - Conferences Richard Georgerian (07-08)

Directors At LargeTerm Expires 12/07 Term Expires 12/08 Term Expires 12/09 Ex Officio (without vote)Jim Bacher Jack Burns Daniece Carpenter Chapter ChairsJohn Freudenberg Murlin Marks Daniel Nachtigall Standing Committee ChairsBansi Patel Richard Pescatore Richard Georgerian IEEE HQDan Roman Ken Thomas Elya Joffe IEEE TAB Division VI Director

Editor:Gary Weidner 1-563-557-0717 (v) 1-563.557.0725 (fax) [email protected]

Co-Editors:Michael S. Morse Ph. D. [email protected] Nute [email protected]

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Longmont, CO on October 22–23, 2007.Austin, TX is the venue for 2008. Canada isbeing considered as a venue for 2009. Weare open to suggestions from our membership,so please provide additional preferred sitesto hold our conferences.

Enjoy the newsletter and consider contributingarticles yourself for publication in your areasof interest. Sincerely,

Henry BenitezIEEE Product Safety Engineering [email protected]

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Richard Georgerianvoice: (303) 833-2327e-mail: [email protected]

People Looking To Start Chapters

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Technically Speaking

by Richard NuteJune, 2007

Safety Critical Components

Here are several definitions of a safety-criticalcomponent:

1. A component which affects the safety of theequipment. All components in primary circuitry aresafety critical. Other components which protect theequipment under normal and fault conditions, suchas thermal switches, optocouplers, etc. are alsosafety critical. (http://www.i-spec.com/IEC_60950/glossary.html)

2. Electrical Safety Critical Parts are those electricalcomponents or assemblies used in a power orsafety circuit, whose proper operation is critical tothe safe performance of the system or circuitincluding but not limited to the following:1) All electrical components acting as a protective

device to interrupt current in an abnormalcondition such as circuit breakers, circuitprotectors, fuses, overload or thermal relays.

2) All components and wiring for the EMO systemincluding power supply, EMO contactor orinterrupting device and pushbuttons.

3) All hardware or firmware components andwiring for safety interlock circuits.

4) All devices that are in an area that is classifiedas a Hazardous Location must have theappropriate rating for the area such as Class IDivision I or Class I Division 2 unless listed asintrinsically safe.

5) Those components that upon evaluationpresent a risk of fire or shock in their use orapplication and are risk ranked per SEMI S10with a medium or higher ranking.

( h t t p s : / / s u p p l i e r. i n t e l . c o m / s ta t i c / E H S /3prtycriticaleleccomp.pdf)

3. “Where failure of components and assembliescould result in a risk of electric shock, fire, personalinjury,” or affect “Prevention and Control ofUnintended Releases” of HPMs, those componentsand assemblies ARE SAFETY CRITICAL. They“should be certified by an accredited testinglaboratory and used in accordance with themanufacturer ’s specifications, or otherwiseevaluated to the applicable standard(s)”. (http://d o m . s e m i . o r g / w e b / w F i l e s . n s f / L o o k u p /

Safety_critical_component/$file/Safety_critical_component.pdf)

These three definitions are quitedifferent. The common thread isthat, somehow or other, the safety-critical component affects the safety of the equipment.Let’s examine these definitions in detail.

The first definition states that all components in theprimary circuit are critical components. I would agreethat all primary circuit components are candidates forsafety-critical components, but not necessarily aresafety-critical components. For example, the resistorsused in the control circuits of a switching-mode powersupply are not likely to be identified as safety-criticalcomponents. I’ll discuss why further in this article.

The first definition also identifies “components whichprotect the equipment under normal and faultconditions” as safety-critical components. Well, I wouldagree for components that protect a person, but notfor components that protect the equipment. From asafety point of view, I don’t care whether the equipmentself-destructs as long as in doing so, it is not likely toinjure a person.

The second definition states that a safety-criticalcomponent is one “whose proper operation is criticalto the safe performance of the system or circuit.” Thedefinition gives some examples such as fuses,emergency off (EMO) components, interlockcomponents, and components that “present a risk offire or shock in their use or application.” I agree thatthese examples are indeed safety-critical components.Note that this definition requires the proper operationof a safety-critical component. I’ll discuss this furtherin this article.

The third definition seems to contradict the seconddefinition. This defines a safety-critical componentas one whose failure leads to “a risk of electric shock,fire, personal injury.” Furthermore, such componentsshould be certified, but does not say anything aboutwhat the component should be certified for.

We can see that the term “safety-critical component”has several meanings, some seemingly contradictory,and none of which is really satisfactory.

Let’s first look at whether a safety-critical componentis one whose proper operation maintains safety or one


Continued on Page 8

whose failure leads to a risk of injury. Indeed, theseare not contradictory, but are complementary.I’ll explain later.

If the failure of a component leads to a likelihood ofinjury, then the component must be designed such thatit is not subject to failure for the lifetime of theequipment. Such a component would be a safety-critical component. And, in many cases, it would needto be certified to safety requirements applicable to theparticular component, which ultimately means thecomponent is not likely to fail when subjected to therigors of use. An example of such a component wouldbe a Y2 capacitor.

Alternatively, if the failure of a component leads to alikelihood of injury, then a second component or safetyscheme must be installed so as to mitigate theconsequences of failure of the first component. Thissecond component or safety scheme is a safety-criticalcomponent.

Let’s look at some examples. Consider a system ofbasic insulation and supplementary insulation. Failureof basic insulation could lead to an electric shock injury.However, the supplementary insulation mitigates thefailure of the basic insulation, so the supplementaryinsulation is a safety-critical component.

But, what about the basic insulation? Clearly, we havealways considered basic insulation as a safety-criticalcomponent. Why? If the failure of basic insulation ismitigated by supplementary insulation, then what isthe justification for basic insulation being designatedas a safety-critical component?

If the supplementary insulation did not exist, then thebasic insulation provides protection against electricshock. In other words, under normal operatingconditions, basic insulation provides protection againstelectric shock. So, basic insulation is a safety-criticalcomponent.

We have two kinds of safety-critical components. Thefirst kind is one that provides safety under normaloperating conditions and may be subject to failure.The second kind is one that provides safety undersingle-fault conditions.

With these principles in mind, let’s take another lookat the first definition of safety-critical component. Itsaid that all components in the primary circuit aresafety-critical components. I said primary componentsare candidates for safety-critical components.

Okay, which components in the primary circuit provideprotection against electric shock? Consider that

protection against electric shock, first and foremost,is provided by insulation; such insulation has the name“basic insulation.” So, with respect to electric shockfrom the primary circuit, we must identify all of thebasic insulations. These would include the insulationof the appliance coupler, the insulation of the primarywires, some portions of the insulation of the printedwiring board, and, of course, the transformer primary-secondary insulation. All of these basic insulationsprovide safety under normal operating conditions andare safety-critical components of the first kind.

These same basic insulations are expected to fail.Consequently, the equipment must include the secondkind of safety-critical component – the kind thatprovides safety under single-fault conditions (failureof basic insulation).

We ’ve already mentioned that supplementaryinsulation is the second kind of safety-criticalcomponent. Another second kind of safety-criticalcomponent is protective earthing. If basic insulationshould fail, then the earthing scheme will carry thefault current back to the neutral conductor and theinstallation overcurrent device should then open thecircuit. So, the earthing scheme is a safety-criticalcomponent. But, the earthing scheme is comprisedof a number of components such as wires, terminals,and fasteners. Each of these components of theearthing scheme is a safety-critical component.

So, now we have normal-condition safety-criticalcomponents and fault-condition safety-criticalcomponents.

Let’s return to the primary circuit components. Assumea switching-mode power supply. If one of the inputrectifiers should fail short, the input fuse will open.So, a fault opens the fuse. This means the fuse is afault-condition safety-critical component.

The question is: What hazard does the operation ofthe fuse prevent? Putting this another way, if the fusewas not in the circuit, what would be the result of ashort-circuit of one of the input rectifiers? Assuming abridge rectifier, then short-circuiting of one rectifierwould result in at least one other rectifier in the bridgeto be across the power line, resulting in rapid andsevere overheating. And, maybe, a fire.

As a general rule, a fuse provides protection againstfire. (A fuse *may* provide protection against otherhazards, but such other protections are not beingdiscussed here.)

So, what is the normal-condition safety-critical








component that provides protection against fire?

First, note that equipment fire does not occur undernormal conditions. Equipment fire only occurs in theevent of a fault.

We can examine this in the same way in which weexamined basic insulation and found it to be a safety-critical component. If we don’t have a fault-conditionsafety-critical component (fuse), and if a fault conditionshould occur, what is the component that wouldoverheat and cause a fire?

In the bridge rectifier, the component that overheatsis not the one that is shorted, but one of the otherrectifiers. So, that rectifier becomes a normal-conditionsafety-critical component because under normalconditions it does not overheat and cause a fire.

Now we ask: Aren’t all components normal-conditionsafety-critical components because under normalconditions they do not overheat and cause a fire?

The answer is no. If we now consider the controlcircuits of a switching-mode power supply, we canintroduce faults which do not cause overheating.Components that do not overheat and cause a fireunder fault conditions are NOT safety-criticalcomponents. If a component does not overheat andcause a fire under fault conditions, then a fault-condition safety-critical component (e.g., fuse) is notrequired.

Often, the bulk capacitor of a switching-mode powersupply is identified as a safety-critical component.Applying our rule, what happens if there was no fuseand if the capacitor is shorted? The bridge rectifierquickly overheats and may cause a fire. So, the bridgerectifier must be provided with protection againstoverheating, which is provided by the fuse. So, thebridge rectifier is the normal-condition safety-criticalcomponent, and the fuse is the fault-condition safety-critical component. The capacitor is NOT a safety-critical component.

Indeed, components that are faulted are rarely safety-critical components. If the equipment remains safe inthe event of a component fault, then we have shownthat that component is not critical to safety, even inthe event of a fault.

So, we have two kinds of safety-critical components.The first kind is a component that provides safety undernormal operating conditions. The second kind is acomponent that provides safety under single-faultconditions.

I don’t like the term “safety-critical component.” First,it is abstract. Second, it doesn’t have a consistentdefinition. Third, the word “component” seems toexclude insulation and earthing systems, both of whichare safety-critical.

Consider basic insulation and supplementaryinsulation. Basic insulation provides protection undernormal operating conditions. Supplementary insulationprovides protection in the event of a fault of basicinsulation, i.e., under single-fault conditions.

We could carry this theme over to safety-criticalcomponents. We could name the two kinds of safety-critical components as “basic safety-criticalcomponent” and “supplementary safety-criticalcomponent.” A bit of a mouthful, but it gets the pointacross.

Instead of “safety-critical component,” I like the word“safeguard.” Immediately, it conjures up some physicalthing, so it is not abstract. I define “safeguard” as adevice or scheme that provides protection against ahazard.

Now, we can have a “basic safeguard” that providesprotection under normal conditions, and we can havea “supplementary safeguard” which provides protectionunder single-fault conditions.

*****

If you have any comments or questions about thisarticle, please send to Richard Nute, [email protected].

If you have a question about product safety, and wouldlike to see the answer published here, please send thequestion to Richard Nute, [email protected]


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The Product Safety Engineering Newsletter is published quarterly during the lastmonth of each calendar quarter. The following deadlines are necessary in order tomeet that schedule.

Closing dates for submitted articles:

1Q issue: February 12Q issue: May 13Q issue: August 14Q issue: November 1

Closing dates for news items:


Closing dates for advertising:


eDJ Publication Schedule

The eDJ is published as a special section of the PSEN.Contact Mike Sherman for details.

We need papers,news, articles,

etc. for the

Newsletter,

eDJ

and Symposium.

Intent to present and topic (e-mail) April 29, 2007Draft e-paper June 1, 2007Notification of Acceptance July 6, 2007Complete e-paper August 17, 2007

Symposium Author’s Schedule:


Effect of Thin Solid Insulating MaterialWhen Verifying Clearances by Electric

Strength Test

by Lal Bahra

Various standards prescribe clearance requirementsusually in the form of tables. The prescribed clear-ances in the tables are an indirect measure of theelectric strength of air insulation. By definition, aclearance is a shortest distance between two con-ductive parts through air. Clearance is designed towithstand the maximum peak voltage that this short-est distance will see including any transient over-voltages. If the voltage goes above this voltage,there is a possibility that the clearance may break-down. Therefore, the tables for clearances usuallyhave a built-in margin.

Another way of determining the electric strengthof air insulation is by actually conducting an elec-tric strength test. The electric strength test voltageis determined by taking into account the maximum

peak voltage that will appear across a clearanceincluding transients and repetitive peaks. If a thinsolid insulating material such as a coating over atrace or a terminal in series with the clearance thenthe electric strength test can still be used to test theelectric strength of air insulation.

Table A.1 in IEC 60664-1 gives the maximum with-stand voltage for a certain clearance in terms ofpeak impulse voltage, ac voltage and dc voltage.From the data in the table, it is apparent that thewithstand voltage is directly proportional to theclearance distance. As the distance increases, thewithstand voltage also goes up. The chart belowshows the relationship of the withstand voltage toclearance distance.

Continued on Page 14








It is clear from the above that electric strength testthat is based on the maximum peak voltage theclearance will see can be used to verify the requiredclearance. The electric strength test voltage mayhave a margin added to insure a similar margin asprovided by the tables.

The new hazard-based safety standard that is beingdeveloped by TC108 of IEC is going to offer thisalternative approach of verifying the clearances byelectric strength test.

In a majority of the times, the distance betweentwo conductive parts is through air but in someinstances there may be a coated trace or a coatedterminal which adds a solid insulating material inseries with the clearance. There was some skepti-cism if electric strength test method of verifyingclearances is a suitable approach or not when a thinsolid insulating material is added in series with aclearance. The reason for this skepticism is that in-sulating materials have higher dielectric constantcompared to air and in general they can withstanda higher electric strength per unit distance than air.If the insulating material is solid insulating materialor thin sheets of insulation (other than enamel) thenthe criteria for accepting solid insulation applies asgiven in the applicable standard. Enamel is usuallynot accepted as an insulating material but that maychange in the future as TC 96 (IEC technical com-mittee responsible for basic safety of transformers)is developing requirements for a special grade ofenamels as insulating materials that may be accept-able at par with other solid insulating materials.

Enamel on a winding wire or coating on a terminalor a trace may withstand 3 kV or more and sinceenamel is not accepted as an insulating material,question arises if the electric strength will ad-equately verify the required clearance (this criteriadoes not apply if enamel or coating serves as solidinsulation. It applies only when enamel or coatingis a thin solid insulation in series with the clear-ance).

If an electric strength test voltage is applied be-tween two conductors having a clearance in series

a solid insulating material such as enamel or coat-ing, then the voltage divides inversely proportionalto the dielectric constant of the solid insulatingmaterial and air. The dielectric constant of air is 1.The solid insulating material usually has a higherdielectric constant. Materials commonly used asenamel or as coatings are polyurethane, polyester,polyester-imide, polyamide-imide, etc. Using themaximum thickness commonly used for enamel, thevoltage drops across the air gap and the insulatingmaterial can easily be calculated.

For further information on types of enamels andtheir thicknesses, please see:

www.enameledwire.com/EnameledWireCatalogue.PDF

For dielectric constant data, please see:www.clippercontrols.com/info/dielectric_constants.html

The calculations are shown for enamels made fromtwo materials, Polyester and Polyamide. The maxi-mum thickness of 0.04 mm for enamel (as describedat the website given above) is used to calculate thevoltage drops as shown in the table given below.For all practical purposes, almost all the voltagedrop is across the air. The graph at the end of thispaper shows the voltage drop across air clearanceversus a certain thickness of the insulating mate-rial. The voltage across air starts to fall rapidly whenthe distance through air falls below the mains tran-sient overvoltage. Therefore, as long as the dropacross the air part of the clearance distance is 2500V or more, we can safely say that given the marginin electric strength test voltage used for testing theclearance, the air part of the clearance is testedappropriately for the peak voltage it actually sees.This will be the case in majority of devices [unlessthe designed clearance is unduly low (clearance isnot designed properly to begin with)]. The clear-ance will still be sufficient if enamel is not present(in case the enamel gets damaged).

http://www.enameledwire.com/EnameledWireCatalogue.PDF

http://www.clippercontrols.com/info/dielectric_constants.html


Continued on Page 16

Calculations for voltage drops across air gap during the electric strength testEnamel Material: Most commonly used material is Polyester resin or polyester, 0.04 mm thickDielectric constant for Polyester: 5 (can vary slightly from website to website)

Dielectric constant for air: 1Supply voltage: 230 V having a mains transient overvoltage of 2500 V peak (see IEC 60664-1)

Required Withstand voltage = VP = V

PSI + V

AFormula used for calculation (voltage divides inversely proportional to the dielectric constant):

and

WhereV

P is the max peak test voltage

VPSI

is the max peak voltage that will appear across the solid insulating materialV

PA is the max peak voltage that will appear across air

TSI

is the thickness of the solid insulating materialK

SI is the dielectric constant of the solid insulating material

TA is the clearance or distance through air

KA is the dielectric constant of air which is equal to 1

For Example, for a 230 V system, the mains transient = 2500 V.Therefore, the withstand voltage (without margin) = 2500 (thickness of enamel/5 + air gap/1) x clear-ance = 2500 (0.04 / 5 + 2 / 1 for 2 mm air gap) = 2500 (0.008 + 2) = (10 V across enamel + 2490 Vacross the air gap).Test voltage: 2950 V peak impulse (from IEC 60664-1) taking margin into account.

( )

+=

K

T

/KT /KT

V V

SI

SI

AASISI

PPSI

( )

+=

K T

/KT /KT

V V

A

A

AASISI

PPA








Table for calculations

ConclusionIf enamel or coating is not part of the clearance, the electric strength test is sufficient to verify a clear-ance. If enamel or coating is in series with a clearance that is being verified by the electric strength test,the voltage drop across the enamel or coating is negligible (for a reasonably designed clearance). How-ever, if enamel or coating forms solid insulation between two conductive parts, that is not the subject ofthis paper. Requirements for solid insulation will apply in that case.The following graphs show the voltage distribution across air and the insulating material.

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Lal Bahra is a P.Eng. at Dell Inc.








by Doug Nix

Each year in March the Robotic Industries As-sociation and the Canadian Standards Asso-ciation get together to host the Robot SafetyConference in Toronto. This conference is animportant event for robot system integratorsand robot users, including members of JointHealth and Safety Committees in plants whererobots are used.

This year the program started with a pre-con-ference training day on Monday, 25 March.The program for that day included sessionson CSA’s Z460 Control of Hazardous Energy– Lockout and other means, the Essentials ofConducting a Pre-Start Health and SafetyReview, Understanding the CSA Z434 robotstandard, An Introduction to Risk Assessmentand Control Reliability, Basic Safety CircuitDesign, and finally a Risk Assessment Exer-cise.

Tuesday was the first full day of the confer-ence, with presentations from CSA and RIAon future developments in the robot safetystandard, case studies on a variety of topicsand a session on safeguarding selection justbefore lunch.

The most significant items were the announce-ment by CSA of the launch of the new CSAZ462 standard, and the launch of the new CSArisk assessment standard committee.

CSA Z462 is an adoption of the NFPA 70EStandard for Electrical Safety in the Work-place, which covers arc flash hazard protec-tion. This is a very significant standard. Hun-dreds of electrical workers are injured by arcflash every year. In the last edition of the Ca-nadian Electrical Code, NFPA 70E is directly

referenced. This standard includes require-ments for labeling of electrical panels and de-fines the types of personal protective equip-ment required for work on live electrical equip-ment. Many large companies are alreadyadopting this standard, and more will soonfollow.

The striking of a CSA Technical Committee todevelop a CSA risk assessment standard isalso important. At the moment, the only “Ca-nadian” risk assessment methodology is foundin CSA Z434 and CSA Z432. This method hasbeen adopted from RIA’s R15.06-99 RobotSafety Standard. This will be an importantstandard to watch in coming months.

RIA announced the release of a new Techni-cal Report, ANSI RIA R15.106 2006, Teach-ing Multiple Robots. This report provides someimportant guidance on approaches to systemdesign related to the specific hazards that arecreated when multiple robots are implementedin close quarters. If you design systems us-ing multiple robots, you need to get a copy ofthis report.

CSA and RIA announced the planned adop-tion of ISO 10218, the international standardon robot safety. The plan is to adopt the ISOstandard following the release of the next edi-tion. This means that the North American stan-dards as we know them today will disappearand be replaced by the international docu-ment, possibly with a few National Deviations.This will allow robot manufacturers to build a“world robot” product that can be deployedanywhere in the world. It also means that ro-bot system integrators can take advantage ofcommon global requirements, designing sys-tems in the same way regardless of the finalinstallation destination.

2007 CSA/RIA Robot SafetyConference Report


The afternoon continued with more case stud-ies, including a session by Tom Doyle of In-dustrial Safety Integration on the cost effectsof system downtime due to injury events. Theafternoon wrapped up with a demonstrationby a number of the presenters on stoppingperformance measurement and the determi-nation of safe distance for light curtains, areascanners and similar equipment.

The final day of the conference included anoverview of control circuitry followed by casestudies. Doug Nix presented on the newestedition of ISO 13849-1, Safety of Machinery– Safety Related Parts of Control Systems,Part 1: General Principles for Design. This isa significant update to this important standard.The new version introduces the concept ofPerformance Levels (PLs) and provides ameans to determine the PL required for anapplication based on the risk assessment.Using component data, the performance of asafety circuit design can be analyzed and thenmodified to provide the reliability required bythe risk assessment. The standard maintainsthe well-known reliability categories (B, 1-4)and improves on their application. This stan-dard is certain to have wide-reaching effecton international, EU and North American stan-dards. If part of your work involves the designof safety related controls, you need to knowand apply this standard in your daily work.

The morning wrapped up with a panel discus-sion with the attendees, giving the conferencegoers the chance to ask the presenters someof the tough questions that they haven’t beenable to get answered.

The afternoon was filled with three all-after-noon sessions: a Z432 workshop, Using RiskAssessment in Safeguarding Automated Sys-tems and Advanced Safety Circuit Design. GilDominguez of Rimrock Automation chaired theAdvanced Safety Circuit Design session. Alsospeaking was Ron Roepke from Pilz Automa-tion and Ian Brough of SICK Optic. The ses-

sion provided attendees with an in-depth lookat some robot-specific circuit designs, includ-ing the implementation of a safety-PLC appli-cation. Gil expanded on Doug’s earlier pre-sentation by walking the attendees throughsome of the ISO 13849-1 calculations neces-sary to determine the Performance Level ofan example circuit.

The conference also included a trade show,with the exhibition hall open during lunch andinto the evening on Tuesday. One of the mostexciting new products being displayed was thenew vision-based area safeguarding systemfrom Pilz. This system uses three camerasmounted in a small housing to develop a 3-Dimage of the safeguarded space. Like a con-ventional area scanner, warning and stopzones can be set, but these zones can nowbe defined in 3-D. The system has not beenofficially released yet, but will be in the nextfew months. Contact your Pilz representativefor more information.

For those new to robot applications, or newto the design requirements for robot installa-tions, this was an excellent conference. Formore information, go to the CSA LearningCentre web site, https://learningcentre.csa.ca/lc_site/beg.asp and search for “robot.”

Doug Nix, A.Sc.T., is a member of the Prod-uct Safety Engineering Society in the Water-loo Region, Canada.








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News and Notes

WHO-IS-IN-WHAT

“WHO-IS-IN-WHAT” projectThe value of networking with others who dothe same work is widely recognized.Therefore, the PSEN recently conducted anetworking experiment.

In this department of the previous issue ofPSEN, we published a survey of PSESmembers to learn what product-safety-relatedcommittees, panels, IEC NationalCommittees, National Committee AdvisoryGroups, trade association technical orstandards committees, and such our membersbelong to. The survey resulted in oneresponse, so the “WHO-IS-IN-WHAT” projecthas been abandoned.

Society

Introducing Our New Mentor

Here is a littleabout Bob Rassa,the new mentorfrom the TechnicalAdvisory Board tothe PSES.

Bob is presentlythe Director ofS y s t e mSupportability atRaytheon’s Spaceand AirborneSystems (formerlyHughes Aircraft), in El Segundo, California,where he is responsible for enhancing thesupportability of Raytheon defense productsand DoD weapon systems, and in assistingRaytheon corporate-wide in theimplementation of CMMI (Capability MaturityModel Integration) and other systemsengineering improvements. He has a 40-yearcareer involving Supportability, IntegratedLogistics Support, Automated Test, SystemsEngineering and Program Management withinIndustry.

Bob’s BSEE is from the University ofCalifornia. He has published numerous papersand delivered presentations, most on radarsystems, logistics, program management, andsystems engineering.

Bob has more than 30 years of experience asan IEEE volunteer, having joined IEEE in1976. He achieved Senior Member in 1993and was elected to the grade of Fellow in2004. Bob initiated the now-annual Panel of

Conference Organizers (POCO), first held inJuly 2006 in Montreal, QE, Canada andscheduled for July 2007 in Vancouver, BC,Canada. This 2-day activity provides IEEEConference organizers, Society/CouncilConference Vice-Presidents, and RegionConference Chairs with all the basicinformation they need in the performance oftheir jobs.

Bob’s hobbies are photography (digital andfilm), automobile racing and autocrossing;automobile collecting; snow skiing (downhill);water skiing; roller blading; biking;motorcycling; automobile rallying; automobileConcourse d ’Elegance; sports cars;automobile mechanics; automobilerestoration; journalism; and 4H.


New PSES Members from March 24, 2007 ThroughJune 27, 2007

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If you do not see your name in the list andare a new member, please [email protected] with the details.

DR LAURENT GENILLOUDMR HOWARD B IDAHORRANDY S BUTTURINIMR GRAEME D MCWILLIAMSMR LORENS AL-HAZAMJONATHAN BERGMANNMR GERALD BOULAY, P.ENG.MR ADRIAN RABAGOLAURA L NILESOSAMA ABUMANSOORMRS KATHY L KINGENG RAYMOND ORTIZMR MARK D WILLEGILBERT C WALTER PEMR THOMAS M DUNAVANMR MICHAEL J GEARHEARTMR DAVID W KAYMR LAWRENCE G OSSOWSKISTEVEN W MITCHELLMR RUBEN J GONZALEZMR MATTHEW S WAKEHAM








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