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OVERVIEW:
Fire and Electrical Hazards from ‘Smart’, Wireless, PLC, and Digital Utility Meters – Part 2

Nina Beety
July, 2019
PDF of full report

Continued

Faulty remote disconnect switch

PG&E whistleblower Patrick Wrigley told the CPUC December 20, 2012:

I was a meter reader for nine and a half years with PG&E in the Marin office before I was illegally fired because I was not intimidated into being quiet with the problems I saw firsthand regarding smart meters’ inaccuracy…The fact that PG&E knows that they do catch on fire when they are remotely turned back on when a customer who is delinquent in their bill finally pays their bill. These meters catch fire. They know it, and they are covering it up.1

Utility companies used to send an employee to manually disconnect electricity from a building. With Smart Meters, the company sends a wireless signal to the meter, and it disconnects the electricity. Electricians have told me it takes strength to turn off a house’s electrical power, and wonder what could be so powerful in a plastic Smart Meter to disconnect this current. With disconnection, there can also be arcing.

From Reno, Nevada:

While city fire investigators have been unable to determine exactly what is causing the meters to combust, the electrician who replaces the burned meters said it appears to him that the “relays” inside the meter are overheating at the switch NV Energy uses to remotely disconnect the power.
“That’s where I think the problems are occurring,” he said. “I even saw a couple here where the meters had just started to turn black. Everything in the panel is fine, it’s just the meter is starting to go.”
A forensic investigator hired by the Reno Fire Department to examine four of the meters involved in the Reno and Sparks fires found that the blazes started within the meter itself.2

In 2011, an electrician wrote:

One of the novel features in the new meters is the incorporation of an internal disconnect switch that the power company purports safely disconnects/reconnects power to the dwelling it supplies by remote control. This disconnect feature is a new and significant change to the old style analog meters. The safety of the new disconnect feature is in question.

As a California Electrical Contractor, I estimate that a 200 amp disconnect enclosure would be sized roughly 20″x 20″x 6″, several times larger than a smart meter. Concerned about this, I asked other electrical contractors’ opinions about the remote disconnect switch. Like myself, they found it hard to believe a 100, 200, or 400 amp disconnect switch can be crammed into a tiny meter enclosure.

He asked:

Is there a full load test for the meter disconnect switch?
If a dwelling’s electrical service is rated at 200 amps, the meter has the potential to have a 200 amp load. Are the smart meter disconnects rated for the maximum potential load of the dwelling it serves?
Are the smart meter disconnects tested and certified to safely disconnect/reconnect under full load conditions?3

Is the disconnect switch certified at all? In the new UL 2735 certifications, are meter models certified without the disconnect switch or other components?

Electrical engineer William Bathgate:

After a hard look at the design and construction of this ITRON meter there are the following observations:
The biggest weakness is the power disconnect, it suffers from a small surface area for the disconnect contact and would be prone to excessive heating and likely result in contact pitting and carbon deposits that are not readily visible by the customer and there is not a sensory circuit that could detect it and report it to the customer or the utility. The design would be prone to creating unpredicted fires.4

Electrical engineers evaluated the British Columbia Utility Commission’s draft report on Smart Meter fire safety concerns (Itron Smart Meters) and among their conclusions found:5

A critical item missing in this Report is any investigation and discussion about the meter’s built-in 200 Ampere disconnect switch. The switch is not CSA6 certified, yet it is being used as a “Service Disconnect Switch” – (CSA Code definition), for which it is not designed. Several requests for technical performance and certification data have been ignored by [utility company] BC Hydro and by Itron. The switch is a potential failure mechanism, in particular during fault conditions, because as described elsewhere, the electrical protection on the HV side of the transformer does not appear to adequately protect the electronic meter from excessive fault current. This BCUC Report states that BC Hydro meters do not need to be certified under the Electrical Safety Regulations, however it also states that BC Hydro is NOT exempt from the Electrical Safety Act. An immediate investigation into the design, certification, testing, operation and capabilities of this disconnect switch is required.

British Columbia never finalized its report.

Insurance adjuster Norman Lambe to New Mexico Public Regulatory Commission:

Unlike analog meters, “smart” meters can turn power “on” or “off’ remotely. Sometimes, during activation of this remote switch, a tremendous burst of power can cause arcing in the meter and result in fire. As noted in the report by EFI Global (CFRE NL 3 b p.4), “All observed damage to the electrical panel and the meter itself is consistent with a fire triggered by extreme heat at the defective switch contacts inside the meter. The heat transferred to the metal clips, which were held in position by a resin-based insulator. the extreme heat ignited the insulator. The ensuing fire burned upward inside the panel, explaining the damage to the circuit breaker located directly above it. Open flame conducts electricity, so the flame drew an arc between the two energized power rails in the panel, explaining the unusual arc patterns in the center circuit on the panel, which was not part of the ’HP’ meter circuit.”7

Portland General Electric removed 70,000 Smart Meters after several house fires, saying the disconnect switch was faulty.

In 2015, Quebec began requiring a separation distance of three linear meters between propane tanks and Smart Meters. The rule only applied to Smart Meters. Utility company Hydro Quebec inspected properties to check compliance. “Until your installation has been checked and found to be up to code, the remote service interruption feature will be deactivated.”8

Circuit boards in electric meters

Electrical engineer William Bathgate:

The fact that there is a set of circuit boards in a power meter at all is a large risk. The circuit boards would not be able to withstand a lightning strike or a power surge without an explosive reaction and likely melting of the circuits. This would lead to total destruction of the unit and lead to a possible fire.9

EMSG Inc.:

Circuit boards aren’t invulnerable either. Over time, they experience a great deal of wear and tear that can deteriorate their performance and functionality. Things such as the weather, humidity, age, and even elevation can affect the condition of a board.10

Smart/digital meter circuit boards are not in a climate-controlled, protected space. They are outdoors, exposed to all the elements including sun, extreme hot and cold temperatures, moisture, wind, dust, rain, and snow.

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Energy Central:

Look under the plastic covers of any smart device, and you will see a printed circuit board and attachments and wires that should be familiar to anyone in the computer industry. This simple fact should give everyone using this equipment pause. Why would this equipment, whose origins and designs have been forged in a throw-away culture of consumer electrics, be durable enough for the demands of the electric utility? The answer is clear. They aren’t.

…Enter the electronic era. Smart meters are already posting failure rates, anecdotally, in the 5% per annum range. This is ten times the failure rate of the traditional meter, and the lifecycle of the product has barely begun. Each additional device connecting the meter to the mothership also has a failure rate. The stability of the grid can only be as good as the weakest device — yet we don’t know which devices are weak. Selecting products for reliability is now essential, but the tools for making associations between products and reliability are entirely missing.11

Melting solder can create new circuit pathways

Fire and excessive heat can melt solder. This is a circuit board vulnerability. If the solder melts, it can create a new pathway, resulting in a short circuit, and potentially, a fire.

Thinner blades, meters don’t fit sockets, pitting

Bobby Reed, a Texas IBEW business manager and troubleshooter for utility company Oncor was fired by Oncor after he testified to the Texas legislature about Smart Meter fires and electrical problems that were regularly occurring and the risk to electrical workers. The complaint to the National Labor Relations Board12 about his firing detailed evidence that Smart Meter fires, burned Smart Meters, overheating, arcing, burned meter sockets, and malfunctioning Smart Meters are regularly occurring and are known to Oncor and CenterPoint, two Texas utility companies.

What I came to testify about today is when they started installing the AMS meters, I noticed that the tickets that I worked or the work orders that I went out on were beginning to be increasingly of the meters burning up and burning up the meter bases. And it’s kind of a two-issue thing there I wanted to bring up to you.

But I can’t tell you how many times I went out. And when I go to a low income house where this lady comes out, this elderly woman, that’s widow woman and she says, you know, “What’s the problem?” And I said, “Well, your meter base burnt up, and it’s your equipment and you have to pay for the repairs before you can get your lights back on.” And she tells me, “Well, I’ve been living here for 45 years, and I’ve never had a problem until they installed that meter.” And that just has happened a lot.

When this started to increase–

SEN. CARONA: Do you believe that it is attributable directly to the meter or perhaps the age of the line in a box?

MR. REED: No, it’s the meter. And I’ve read that about the wiring in the box. But the meter is just a little bit bigger than the old analog meter, and especially for an older house, it’s a 100-amp meter base normally. And when you have to set that meter, it’s a little bigger, and the cover won’t go down. So people have to manipulate that meter in order to get the cover to lock.

But when I started noticing this, I called the union there in Houston and asked them if they were experiencing the same thing. And he told me he would go by the meter shop that next day and then call me. And he called me the next day and said that they are experiencing a significant increase in the meters being turned in that are burnt up from the old analog meters to now, the AMS meter.”

Two reasons identified by union workers were the thinner blades in Smart Meters, and that Landis and Gyr Smart Meters were too big for the meter socket.

Smart meters do not fit into the base properly, leaving a gap which leads to arcing and fires. The base was designed and certified to hold an analog and nothing else.

The meters mentioned were Itron and Landis & Gyr. In California, Itron Smart Meters are used by Southern California Edison, San Diego Gas and Electric, and Los Angeles Department of Water and Power. Landis & Gyr Smart Meters are used by PG&E and Sacramento Municipal Utility District.

The blades of the meters must provide contact with the jaws of the meter socket. If the blades are too thin or the meter isn’t the right size, this causes inadequate contact or gaps, and that will cause arcing. This is a fire hazard and also results in pitting of the metal surface which will increase arcing. Arcing also creates transients which in turn affect the electrical wiring and appliances and electronics.

Sharon Noble, Coalition to Stop Smart Meters BC, has been investigating Smart Meter fires for many years and lobbying the government to take action. In 2014, she wrote,

According to electrical engineers in our group, the Canadian Standards Association (CSA) is quite concerned because the base was certified to hold an analog, not an digital meter running on electricity. CSA said the bases could lose their certification because there has been no testing to ensure that the base and the meter are compatible. Due to the thermal resistance created by the corrosion, the electricity begins to arc and these arcs ignite the main insulation wiring causing electrical shorts that start fires.13

Malfunctioning temperature alarms and sensors

Thermal sensors have actually been installed in some meters to notify utility companies of potential problems or shut off the electricity. However, these have malfunctioned as well.

Engineer William Bathgate: “There are supposed to be sensors of high heat within the meter, but it did not detect the condition at my home [with the burned contacts].”14

Take Back Your Power:15

As reported in a 2013 Illinois Commerce Commission (ICC) report,16 some utilities are attempting to mitigate smart meter fire risks by ‘proactive temperature monitoring.’  However, as stated in the ICC report: “The majority of ComEd’s AMI meters (GE) are equipped with temperature sensors and can report their internal temperature on command — [a]though the temperature sensor was not designed for that function. However, a problem with the scans soon made itself known. Apparently, radiofrequencies can enter the meter and cause the temperature sensor to report significantly inaccurate measurements.”

Also, the previously mentioned document17 submitted to the Maryland Public Service Commission in the form of comments contains the following language:
‘T]he meter (BGE uses L&G) burned up despite the sensing device. Although no fire occurred, the safety system failed miserably. “[They] could actually hear the meter sizzling as if something was being fried inside it. “ What this clearly demonstrates is that the remote sensing system the utilities are relying on is hardly foolproof. One can only imagine what would have happened if there had been a real fire.’”

Switching mode power supply surges (SMPS), damaged appliances

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A switching mode power supply (SMPS) in the Smart/digital meter constantly converts the incoming alternating current (AC) to direct current (DC) to power the meter and its electronics. This causes surges. These constant surges go into the home or building along the wiring and to all electronics and appliances and their varistors. A varistor in a piece of equipment can take only so many surges before it fails and destroys the motherboard.

Many people have reported damaged or destroyed appliances and electronics after Smart Meter installations. This can occur weeks or many months later.

RF signal and SMPS transients routed onto building wiring

Every electronic component you purchase needs a connection to ground to work. It protects the circuit by routing the currents to ground. On the 3-prong plug for electronics and appliances is the wire for the ground.

The switching mode power supply (SMPS) in electronic devices creates transient voltage. If the SMPS creates transient voltage above 60 Hz, those transients are normally routed to ground, just like surges.

Smart/digital meters create transients but have no ground path. Therefore, there is no way for the meters to shunt the transients to ground.

Electrical engineer William Bathgate:

On examination of typical meters, including ABB, GE, ITRON and Landis+Gyr, and many others they report that, in addition to its RF transmitter, each wireless digital meter also has a component called the ‘switching-mode power supply’ (SMPS) – switching power supply for short. Its function is to ‘step down’ the 240v alternating current (AC) coming in from the utility pole power lines to the 3.3 to 12 volts of direct current (DC) required to run the meter’s digital electronics which record the electricity usage data and send out the various RF transmissions.

The SMPS function emits sharp spikes of millisecond bursts constantly, 24/7. The SMPS on the commonly used Silver Springs Network, OWS 514 NIC model, for instance, which is within the smart meter models widely installed by PG&E and other utilities throughout their territory, has been measured to emit spikes of up to 50,000 Hz and higher. This constant pulsing of high frequencies, in addition to the RF function, is causing not only interference with other electric and electronic equipment in many homes with smart meters installed, but also is causing havoc with biological systems in its field of exposure. 18

A 2010 report by Cindy Sage/Sage Associates and electrical engineer James Biergiel warned

Typical gauge electrical wiring that provides electricity to buildings (60 Hz power) is not constructed or intended to carry high frequency harmonics that are increasingly present on normal electrical wiring…Harmonics are higher frequencies than 60 Hz that carry more energy, and ride along on the electrical wiring in bursts It may be contributing to electrical fires where there is a weak spot (older wiring, undersized neutrals for the electrical load, poor grounding, use of aluminum conductors, etc.). The use of smart meters will place an entirely new and significantly increased burden on existing electrical wiring because of the very short, very high intensity wireless emissions (radio frequency bursts) that the meters produce to signal the utility about energy usage.

… [W]hen the wireless signal is produced in the meter… it boomerangs around on all the conductive components and can be coupled onto the wiring, water and gas lines, etc. where it can be carried to other parts of the residence or building.

It is an over-current condition on the wiring. It produces heat where the neutral cannot properly handle it. The location of the fire does NOT have to be in close proximity to the main electrical panel where the smart meter is installed.

… For fires that are ‘unexplained’ or termed electrical in nature, fire inspectors should check whether smart meters were installed within the last year or so at the main panel serving the buildings. They should question contractors and electricians who may have observed damage from the fire such as damage along a neutral, melted aluminum conductor or other evidence that would imply an overcurrent condition.

… Faulty wiring, faulty grounding or over-burdened electrical wiring may be unable to take the additional energy load.19

Interference with AFCI/GFCI

Wireless signals and transients produced by the Smart/digital meters interfere with ground fault circuit interrupters (GFCIs) and arc fault circuit interrupters (AFCIs). This interference can make them trip or prevent them from tripping20 PG&E reported this in 2011, though they claimed these were “limited problems.”

In 2014, a Masters degree candidate at the University of Texas studied Smart Meter interference with GFCIs.

It has been reported that the RF transmissions from Smart Meters can induce false tripping events on GFCI outlets installed on temporary construction poles…Controlled investigations in the laboratory have shown that the tripping events are repeatable and it has been found that the RF transmissions from the Smart Meter’s wireless radio are likely the cause of the unexpected GFCI tripping events. The tripping is caused through the coupling of the roughly 900 – 930 MHz transmissions into the sense electronics within the GFCI…It was concluded that both radiative and conductive interference was occurring, both of which could completely independently cause the GFCI to trip…Not only could conductive interference occur between the two devices, but the wire used to power the GFCI off of the Smart Meter was acting as an antenna.21

Certified home inspector Jim Hime:

Smart meters are now being installed in my area. Smart meters are starting to trip AFCI’s as reported by 2 electricians I know and work with so far.

As you know, an arc fault breaker looks at an electrical [sine] wave and figures out what’s right and what’s not. When it “see’s” the signature of an arc, it trips. RF (radio frequency) interference has nearly the same electrical signature as an electrical arc.

Guess how the new smart meters talk to the home office? (radio frequency)

Where the electrical panel is located next to the smart meter problems have developed according to my bubba electricians.

This is NOT a builders problem. It is a utility company problem. A builder has no control over a utility company. What can someone do? Write your congressmen and ask that the utility companies go back to the drawing board…22

Moisture, heat, and flammable lithium batteries

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Smart/digital meters are not watertight or hermetically sealed.

Ritenburg & Associates Report, October 24, 2014:

After reviewing the information available, we are of the opinion that moisture and contaminants within the Sensus meter has been a major factor in the meter failures and ensuing fires. We have not found any issues with the new meter installation methods and practices… As there is some danger with destructive meter failures and potential resulting fires, we recommend that the existing Sensus Generation 3.3 meters be replaced as soon as possible. As the existing meter fires have had a close relationship to precipitation levels, SaskPower might wish to consider replacement no later than the end of winter and before the spring thaw and spring rains begin. 23

Smart/digital meters use 1-cell lithium batteries for the memory, and gas Smart Meters use lithium batteries for the RF transmission. Lithium batteries are very flammable to water, causing them to catch fire or explode. Since meter cases are not watertight, batteries are exposed to moisture, including humidity and rain. In a fire, the plastic cases and parts of gas and electric Smart/digital meters will melt and burn, exposing the explosive batteries to water. Furthermore, in coastal areas, there is salt in the vapor, and that salty moisture can corrode the batteries. Components on a circuit board will not last; this salt will cause corrosion including to the solder joints. Over time, this will cause bridging, leading to short circuits and circuit board failures.

Lithium batteries are also vulnerable to overheating which will cause them to explode.

Gas AMI/AMR digital meters containing lithium batteries pose additional threats of ignition of gas lines if gas meters catch fire, melt, or explode.

Risks from AMI/AMR water meters

AMI/AMR digital water meters contain lithium batteries and are a fire risk due to their normal proximity to water. These meters are also commonly located in the public rights of way, and can be near trees and vegetation. New water meter pit covers are made of flammable fiberglass instead of dense concrete in order for the RF signal to pass. These covers and meter plastic components would be destroyed in an externally originating fire or a meter fire.

Water lines could be ruptured if water meters catch fire or explode. If that happens, water pressure and water availability to fight fires will be compromised. This may already have happened in fires.

Analog electromechanical and water and gas flow meters do not contain these ignition sources.

UL certification of meter models that cause fires

In 2012, Underwriters Laboratory said:

UL has a program for Listing of Utility Meters, but since there is no regulation in USA that requires utility meters to be Certified, this is an entirely voluntary program.24

However, the public increasingly raised the issue of no UL certification of Smart Meters especially in light of fires and electrical problems.25

In 2015, MetLabs acknowledged fire hazards and other problems, and announced a new voluntary UL standard for these meters:

In the past, design flaws in smart meter units have been known to cause serious fire hazards and spotty performance. This has caused a lot of concern for utilities and manufacturers of smart meters….To prevent problems like this, a new voluntary safety standard – UL 2735 – has been created for electric utility meters…26

However, doubts have been voiced about this new testing.

Insurance adjuster Norman Lambe told the New Mexico PRC in 2016:27

UL has a new certification standard that is said to have been developed to insure the safety of “smart” meters, UL Standard 2735. But, even this certification is not sufficient. The very meters that have received this certification, Sensus and Landis & Gyr, have caused fires.

For instance, the Smart Meters in Saskatchewan that caused fires were sent for certification, and “…the Sensus meters passed all safety tests under the UL 2735 Standard for Safety for Electric Utility Meters, which test resistance to flame, water, temperature swings and exposure to various voltages and other extreme operating conditions.”28

Underwriters Laboratory and other certification companies may remove the remote disconnect switch and other components before testing. These companies may test components individually, not as a complete meter. Meters may only be tested in a laboratory and in isolation, not under “real world” conditions — being connected to a building, in an analog-certified socket, in a mesh network, PLC, or cellular system, and as part of a bank of meters.

Continued in Part 3

1 California Public Utilities Public Participation Hearing (PPH), December 20, 2012, Santa Rosa, From the official transcript
http://www.scribd.com/doc/118148663/CPUC-PPH-Santa-Rosa-Transcript

2 https://www.rgj.com/story/news/2014/09/21/reno-smart-meter-fires-widespread-first-feared/15897355/

3 http://1hope.org/hopeblog/unknown-safety-of-smartmeters-new-disconnect-switch/
Unknown Safety of New On-Off Switch in Smart Meters:
CPUC Meter Safety Testing Confirmation Needed.

4 http://www.stopsmartmetersbc.com/wp-content/uploads/2017/04/Evaluation-of-the-ITRON-Open-Way-AMI-Meter-PowerPoint-by-William-Bathgate-Jan.12-2017-v8-3-2-2017.pdf

http://www.stopsmartmetersbc.com/bcuc-smart-meter-fires-the-failure-to-protect/
Cited in http://tinyurl.com/SMFireReport p. 34

5 http://www.stopsmartmetersbc.com/bcuc-smart-meter-fires-the-failure-to-protect/
http://tinyurl.com/SMFireReport p. 77

6 Canadian Standards Association

7 http://www.electronicsilentspring.com/wp-content/uploads/2016/10/nl.pdf — p. 8

8 http://ofsys.hydroquebec.com/T/OFSYS/SM2/2/S/F/4947/13087532/Dnm3qyNW.html

9 http://www.stopsmartmetersbc.com/bcuc-smart-meter-fires-the-failure-to-protect/
http://tinyurl.com/SMFireReport
p. 34

10 http://emsginc.com/resources/5-most-common-pcb-repairs/

11 https://www.energycentral.com/c/iu/dirty-little-secret-smart-devices-are-consumer-electronics

12 NLRB Decision and Order: http://apps.nlrb.gov/link/document.aspx/09031d4582177a1a
Bobby Reed’s Senate testimony is on p. 13-14

13 http://marylandsmartmeterawareness.org/smart-meter-news/maryland-smart-meter-awareness-and-anne-arundel-county-environmental-council-request-moratorium-on-all-smart-meter-installations-in-wake-of-house-fires/

14 https://mi-psc.force.com/sfc/servlet.shepherd/version/download/068t0000001UX3MAAW

15 https://takebackyourpower.net/smart-meter-fire-risk-liability-is-undeniable-and-unprecedented/

16 https://skyvisionsolutions.files.wordpress.com/2014/08/icc-smart-meter-fires-staff-report-2013.pdf

17 https://skyvisionsolutions.files.wordpress.com/2014/08/comments-on-meter-fires-from-msma-final.pdf

18 https://www.defiltersllc.com/new-critical-problem-with-smart-meters/

New Critical Problem with ‘Smart’ Meters — Just When You Thought It Was Safe to Opt-Out, William Bathgate

19 http://eon3emfblog.net/wp-content/uploads/2010/09/Wireless-Smart-Meters-and-Potential-for-Electrical-Fires.pdf

Wireless Smart Meters and Potential for Electrical Fires, Cindy Sage, Sage Associates and James J. Biergiel, EMF Electrical Consultant, July 2010

20 https://skyvisionsolutions.files.wordpress.com/2014/08/pge-gfci-and-afci-rf-interference.jpg

21 https://rc.library.uta.edu/uta-ir/bitstream/handle/10106/24887/Donahue_uta_2502M_12842.pdf?sequence=1&isAllowed=y

“The Study of the Effect of Smart Meter RF Transmissions on Ground Fault
Circuit Interrupters” Simon Donahue, December 2014, University of Texas

22 https://forum.nachi.org/t/smart-meters-tripping-afcis/63603

“Smart Meters tripping AFCIs”, Jim Hime, October 2011, InterNational Association of Certified Home Inspectors

23 http://www.saskatchewan.ca/~/media/news release backgrounders/2014/oct/3 ritenburg final report.pdf

CIC SaskPower Smart Meter Program: Electrical Fire Investigation and Review, Ritenburg and Associates, Ltd., October 24, 2014 (p. 3, 26)

24 http://www.psc.state.fl.us/Files/PDF/Utilities/Electricgas/SmartMeters/09_20_2012/WorkshopComments/MaredyHanford.pdf — p. 4

Correspondence with Mike Chan, Underwriters Laboratory, Sept 24, 2012 (emphasis added)

25http://www.smartgridtoday.com/public/ComEd-asks-GE-to-get-UL-seal-based-on-consumer-expectations.cfm link no longer works

26 http://www.metlabs.com/blog/meters/new-ul-2735-electric-utility-meter-standard-ensures-safety-and-performance/ (emphasis added)

New UL 2735 Electric Utility Meter Standard Ensures Safety and Performance

Posted in https://smartmeterharm.org/2016/01/05/international-lab-says-smart-meter-design-flaws-known-to-cause-serious-fire-hazards/

27 http://www.electronicsilentspring.com/wp-content/uploads/2016/10/nl.pdf (emphasis added)

28 https://www.greentechmedia.com/articles/read/sensus-smart-meters-pass-ul-safety-tests-but-fire-concerns-remain

https://smartmeterharm.org/2021/06/03/report-on-fire-and-electrical-hazards-of-smart-and-other-digital-meters-part-2/