This post is by Steve Hayes, EMC & Safety Managing Director, TRaC
Over recent years there have been a number of instances where the safety of electrical products has been comprised by EMC phenomena. Toasters are often used as an example: in the past when a toaster was "off", it really was off, but nowadays toasters are microprocessor-based, creating the possibility of a transient on the mains power supply initiating a toasting cycle which could present a serious fire risk.
There a two thought processes of how to integrate EMC testing into a safety assessment.
Over recent years there have been a number of instances where the safety of electrical products has been comprised by EMC phenomena. Toasters are often used as an example: in the past when a toaster was "off", it really was off, but nowadays toasters are microprocessor-based, creating the possibility of a transient on the mains power supply initiating a toasting cycle which could present a serious fire risk.
There a two thought processes of how to integrate EMC testing into a safety assessment.
The first is to simply take the levels as required by the EMC Directive (in Europe) and add a severity level to them (for example electrical transients goes from 1 to 2kV spikes).
This is OK to a point. However when the severity level is applied to all the tests required, the additional time and cost may be excessive.
The alternative approach is to undertake a risk assessment to identify where additional, higher level, testing is justified by the potential risk. For our toaster example, the risk of exposure to a high RF field around 2.45GHz - the frequency used by microwave ovens - is significant, whereas at other frequencies normal levels should apply.
In practice allowing the safety people to "write" the EMC tests by using effective risk assessment is the safest approach, ensuring that testing focuses on preventing the problems that are potentially most dangerous. A "one size fits all" approach can't discriminate in the same way.
Surely the best approach is to apply the additional testing based on a sensible risk assessment. If, however, manufacturers aren't proactive in adopting this method then legislation could force an over-zealous approach.
We are some way off having to perform EMC tests as part of all electrical safety inspections, but if manufacturers take the cynical approach, the cost of test and certification could increase.
Previous Certification & Test entries:
* Four Things You Need to Know About Seismic Testing
* Is UK really sharpening its teeth for CE Marking Enforcement?
* What's the difference between the UL and MET Listed Marks?
* Military environments warrant separate standards?
* Military CE Marking - Let's Work Together
* Why are there so many emissions standards?
* What's the point in CE Marking military equipment?
* Navigating the approvals process for RF enabled medical devices
* Seven Reasons to Conduct Pre-Compliance EMC Testing
* And you thought your EMC tests were difficult!
* Regulation of energy efficiency presents new certification challenges
* Why does volcanic ash cause aircraft flights to be cancelled?
* 14 environments with explosive atmospheres
* Electronics in explosive atmospheres - standards stop things going bang!
* A guide to reliability testing, part 3 - Environmental Stress Screening
* A guide to reliability testing, part 2 - HASS
* A guide to reliability testing, part 1 - HALT
* Certification & Test: Flammable atmospheres - A change to the ATEX Standards for zone 2 equipment
* Certification & Test: How to make sure products comply with Noise at Work regulations
* Certification & Test: The impact of the Noise at Work Directive on your designs
* Certification & Test: How am I going to test that?
* Certification & Test: Electrical safety is still important!
* Certification & Test: Why bother with vibration testing?
* Certification & Test: Do I really need earthquake testing?
* Certification & Test: Differences between earthquake and vibration testing?
* Certification & Test: Safety - it's a complex business!
* Certification & Test: What's the point of a Notified Body?
* Certification & Test: The difference between Bluetooth and ZigBee testing?
* Certification & Test: Is above 1GHz the new Wild West?
* Certification & Test: Where have all the ZigBee products come from?
This is OK to a point. However when the severity level is applied to all the tests required, the additional time and cost may be excessive.
The alternative approach is to undertake a risk assessment to identify where additional, higher level, testing is justified by the potential risk. For our toaster example, the risk of exposure to a high RF field around 2.45GHz - the frequency used by microwave ovens - is significant, whereas at other frequencies normal levels should apply.
In practice allowing the safety people to "write" the EMC tests by using effective risk assessment is the safest approach, ensuring that testing focuses on preventing the problems that are potentially most dangerous. A "one size fits all" approach can't discriminate in the same way.
Surely the best approach is to apply the additional testing based on a sensible risk assessment. If, however, manufacturers aren't proactive in adopting this method then legislation could force an over-zealous approach.
We are some way off having to perform EMC tests as part of all electrical safety inspections, but if manufacturers take the cynical approach, the cost of test and certification could increase.
Previous Certification & Test entries:
* Four Things You Need to Know About Seismic Testing
* Is UK really sharpening its teeth for CE Marking Enforcement?
* What's the difference between the UL and MET Listed Marks?
* Military environments warrant separate standards?
* Military CE Marking - Let's Work Together
* Why are there so many emissions standards?
* What's the point in CE Marking military equipment?
* Navigating the approvals process for RF enabled medical devices
* Seven Reasons to Conduct Pre-Compliance EMC Testing
* And you thought your EMC tests were difficult!
* Regulation of energy efficiency presents new certification challenges
* Why does volcanic ash cause aircraft flights to be cancelled?
* 14 environments with explosive atmospheres
* Electronics in explosive atmospheres - standards stop things going bang!
* A guide to reliability testing, part 3 - Environmental Stress Screening
* A guide to reliability testing, part 2 - HASS
* A guide to reliability testing, part 1 - HALT
* Certification & Test: Flammable atmospheres - A change to the ATEX Standards for zone 2 equipment
* Certification & Test: How to make sure products comply with Noise at Work regulations
* Certification & Test: The impact of the Noise at Work Directive on your designs
* Certification & Test: How am I going to test that?
* Certification & Test: Electrical safety is still important!
* Certification & Test: Why bother with vibration testing?
* Certification & Test: Do I really need earthquake testing?
* Certification & Test: Differences between earthquake and vibration testing?
* Certification & Test: Safety - it's a complex business!
* Certification & Test: What's the point of a Notified Body?
* Certification & Test: The difference between Bluetooth and ZigBee testing?
* Certification & Test: Is above 1GHz the new Wild West?
* Certification & Test: Where have all the ZigBee products come from?
After obtaining his Bachelor's degree in engineering, Jonathan worked for a number of engineering companies prior to obtaining a teaching role at the University of Hull (England). In 1995 he joined KTL, an internationally renowned test laboratory which then became TRaC, as part of the Digital Group specialising in regulatory requirements for digital telecommunications equipment. During his time at the company he has, among other things, been appointed as Senior Protocol Engineer, and Approvals and Homologation Group Manager. Jonathan has actively participated in various technical working groups for the ZigBee Allianceâ and is currently the ZigBee Qualification Group (ZQG) Lead Technical Editor. 
Steve is Managing Director for the EMC and Safety business of TRaC and has been involved in EMC and product approvals for 19 years. In addition to the day to day running of the business, Steve is actively involved in EMC standardisation both in commercial and defence areas. In addition to being the UK Principal expert on EMC standardisation of Industrial, Scientific and Medical (ISM) products he is also the convenor of CISPR/B/WG1 who has the responsibility of writing the International standard, CISPR 11. Steve wrote the CE marking annex to the UK's defence EMC standard as well as being co-convenor of CENELEC TC210/WG9, responsible for writing a guide on approval of military systems with commercial (CE Marking) requirements.
Joe Lomako MSc is the Business Development Manager of Telecoms and Radio at TRaC. He has been involved in the testing and compliance industry for over 15 years. Prior to joining TRaC Joe specialised in EMC, EMF Exposure and Radio compliance.
Appointed Test Manager in 2007, following three years as Projects Manager at TRaC, having previously worked as Head of Environmental Testing at another UKAS accredited test house. Over 20 years' experience of modelling, testing and measurement in the structural dynamics and seismic fields.
Chris has worked in electrical safety compliance for over 17 years. Having previously worked for BSI, he joined TRaC in 1996, progressing through a number of testing roles before becoming Safety Product Manager in 2006.
Appointed Commercial Manager - Analysis in November 2009. Prior to joining TRaC, he was the Business Development Manager at Onward Technologies, an engineering services company based in India. Graham has spent over 20 years working in the CAD / CAE domain selling both engineering services and engineering systems. 
Stephen Tait joined KTL, an internationally renowned test laboratory which then became TRaC, as part of the Telecom Group specialising in telecommunications product testing for worldwide approvals. Stephen is also responsible for the Telecoms commercial activities within the TRaC group.
Simon Barrowcliff is the Director of the ATEX Notified Body at TRaC. He set up TRaC's Lancashire-based, ATEX business in 2002 and has been heavily involved in EX testing and compliance since then. Simon also runs TRaC's certification schemes for electrical safety under the IECEE CB scheme. He is a chartered electrical engineer with more than 20 years experience of product compliance for electrical and mechanical equipment.
Appointed Managing Director in November 2007. Previously he was Test Facilities Manager for Flight Refuelling, part of the Cobham group, and spent his early career in the Environmental Engineering Department of British Aerospace at Stevenage.
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