Reprinted from Mike Holt's Newsletter -
Lightning Protection Standard 780 to be
Deleted by the NFPA!
Mike in response to Lightning Protection.
When I moved from Chicago to Boca Raton I was amazed at the amount of
lightning in the area. Now that I have moved to Central Florida, I really see
Mother Nature at her worst or best depending upon how you see it. The
contractor that built my home furnished a surge suppression system as part of
his package. I don't know if it is a "good" system or a cheap
version but it has served well enough so far.
I am very concerned about the lightning and am going to install a protection
system. I believe that these are two separate and distinct protection systems.
About two years ago I attended a seminar about "early emission lightning
preventor systems". I was very impressed by the technology presented and
very surprised by the number of facilities using the system. I knew that it
was not a UL listed system but that it was tested and listed by ETL.
I have decided to install that system at my home and was quite surprised to
see the information in your newsletter about the home in Huntsville, AL. I'm
quite surprised by some of the comments made by your readers.
The system I anticipate using requires proper surge suppression systems for
all incoming services to the building. My information from this company is
that their system directs the lightning discharge directly into the earth in a
manner they consider much more efficient than other systems.
I have Dear Mike, I have a copy of the letter sent out by the Standards
Council in which they state their intention not to issue the 2000 edition of
NFPA 780 and to withdraw the 1997 edition of NFPA 780 and to terminate the
Project on Lightning Protection.. They are soliciting comments on their
intention and a final action will be taken at the October 2000 meeting.
This action, if finalized, will probably have a great impact on the UL
certification of lightning protection installers since their certification is
based on NFPA 780.
I also understand that the test being conducted by UL and I believe Harger and
maybe others, on lightning protection systems shown in the NFPA Standard have
There appears to be a lot more than going on than a lawsuit over damage to a
home that everybody has an opinion on but that none of them have any
substantial information about.
Regards, Charlie Trout, Ctrout1018@aol.com
Mike’s Comment: Charlie is the Chairman of Code Making Panel 12 for
the NEC, representing the National Electrical Contractors Association (NECA).
Naturally, he understands the NFPA process and I hold his comments about
withdrawing NFPA 780 in high regard. I live in Central Florida and I installed
a traditional lightning protection system (been around since the late
1700’s) on my house. My uneducated and bias opinion is that an “early
emission protection system” has not proven to be effective. I guess we’ll
see how this all turns out in a few months.
Response No. 8
Mike, can you refresh my memory (and maybe some other readers) as to what an
"early emission lightning preventor system" is, and or does or is
SUPPOSED to do?
Bill Walker, BREKLAW@aol.com
Response No. 9
Dear Mike, re: lightening ATTRACTORS or STREAMING EMITTERS or what ever.
I have done inspection on a large college campus here in Pensacola. They had
standard lightening rods on buildings. Then someone sold them one of these
'emitters'. The theory is that a charge of radioactive material in the device
sends out a stream of ions to make a path that goes up to provide a path to
ground (through conventional downleads) to the earth. The thing is real 'sexy'
looking, like a chrome cantaloupe with a chrome Frisbee around it and a little
sharp prong on top and mysterious portholes around the sides. Like a flying
saucer. It is to be installed on a 20 foot mast on top of the building and
connected to one down lead and cost something like $30,000.
This college built a new building, installed all the conduit and downleads for
a standard Faraday cage and then put up one of these. The electrical
maintenance man laughed just like I laughed when I heard the sales pitch. and
saw one. "Snake oil, pure and simple snake oil" it seemed and sure
enough the building got hit on a far corner before a few months went by. The
factory people came down, and paid for damage, and said the steps back on
building and configurations put the corner hit by lightening just outside the
area of protection installed another at no charge and left.
Now the electrical supervisor is a licensed electrical contractor qualifying
them to do maintenance work, though construction is by outside contractors.
The man is knowledgeable and organized. They were in the habit of changing
lightening rods (air terminals) every year to be resharpened, and check
connections, etc. well maintained. Every time a strike hit a building it would
either take out the local fire alarm, or the wiring interconnecting the
buildings on campus, so each had to be logged and noted and corrected. After a
while, according to the maintenance supervisor, he noticed that no more
strikes in the area of the new building. They changed some more buildings, and
problems went away. They have covered a large area (several blocks) and feel
they have gotten their money's worth.
Yes, this is anecdotal. But a recorded history of lightening strikes doing
damage to buildings weekly, to a much lower incidence of strikes has to mean
The local installer is an electrical contractor he had done surge suppressors
on services for years and interconnected driven rods to satisfy cell tower
cites in our area. It sure seems strange, but it seems to work. I think they
have a residential version for something like $3,000.
I found it very interesting to follow the thread that you would reference
every so often, each side calling names and swearing that the other side
didn't know beans and no one with any real scientific evidence.
Oh well. If we don't know how to ground a light standard, why should we be
expected to know how to ground a lighting rod?
Response No. 10
At New Mexico Tech we have been studying lightning terminals for the past ten
years (with some of our support coming from the manufacturers of conventional
lightning protection systems). We have found that several commercial
(so-called) early streamer emission lightning terminals do not provide any
better lightning attachment than an inexpensive pointed metal rod, and
probably provide less protection than an inexpensive blunt rod. (Our results
will soon appear in a paper in the Journal of Applied
Our work is certainly not the definitive statement on early streamer emission
devices, but studies from UK and Australian universities show similar results.
If it is indeed true that an ESE device is no better than a sharpened rod,
then protecting an area of 100 meters in radius with a single ESE device will
provide considerably less protection than will a conventional system. There
are currently no such independent studies -- the only studies which indicate
that ESE devices work are those conducted by the manufacturers of the devices.
It would be good if independent studies were done. However the only parties
with financial interests in such studies are those who make and sell ESE
devices, and those who make and sell conventional lightning protection
systems. The US government, to the best of my knowledge, does not sponsor such
research. The National Science Foundation recently turned us down on a
proposal for such studies.
I do not know of any independent academic or research organization getting
support for such work from federal sources. Thus, we are left with work done
by academic groups (whose results are tainted by the sponsorship of
conventional manufacturers) which show ESE devices do not provide more
protection than conventional air terminals, and work done by manufacturers of
ESE devices (whose results are tainted by their financial interests in the
results) which show that ESE devices are significantly better than
conventional air terminals.
Bill Rison, Professor and Chairman, Electrical Engineering Department
New Mexico Institute of Mining and Technology
Socorro, New Mexico 87801
Response No. 11
Abdul M. Mousa, "The Applicability of Lightning Elimination Devices to
Substations and Power Lines", IEEE Transactions on Power Delivery, Vol.
13, No. 4, October 1998, pp. 1120-1127.
The above paper again confirmed that lightning couldn’t be eliminated and
that any claims otherwise are false. This paper is especially important
because it went through the peer review process twice as discussed hereafter.
First, it was examined by three reviewers in accordance with the practice of
the IEEE Power Engineering Society ("PES"), which does not accept
manuscripts unless they pass this review to establish that the manuscript is
sound and has archival value. Following this, the IEEE announced the
availability of pre-prints of the paper and invited discussions for
publications with the paper in accordance with the practice of the IEEE-PES.
Instead of a discussion, the IEEE got a threatening letter from Mr. Roy
Carpenter, the owner of the largest company, which produces those so-called
lightning elimination devices, claiming that his devices do prevent lightning,
that the contrary statements in Mousa's paper are not founded, and that he
will sue the IEEE if it published the subject paper.
The above threat forced the IEEE to conduct a second peer review of the paper
by three additional referees. This process confirmed that the paper should be
published. The IEEE offered Mr. Carpenter a chance to have his claims examined
by participating with Mousa and others in a panel presentation on this
subject, to be organized by the IEEE-PES and held as part of one of its
regular Summer or Winter Meetings. Mr. Carpenter declined that offer. The IEEE
then published Mousa's paper. This took place about 18 months ago and we have
not heard of Mr. Carpenter since then.
I would be pleased to send a copy of the above paper to interested readers who
do not have easy access to IEEE Transactions. Just send me your complete
mailing address via an e-mail note.
In closing, I have a few words for your readers to reflect on: All it took for
evil to triumph throughout most of mankind's history was that good people
stood back and did nothing. I do not think that this will change and I do not
blame the many silent others who believe the same like myself but avoid
battling with people like Roy Carpenter and R.W. Rapp.
In this world we live in it is the responsibility of the potential buyer of
such garbage lightning protection devices to protect himself by finding out
the facts before throwing away his/her money. With the subject being so
technically complex, however, I chose to join the courageous Dr. Bill Rison,
the 17 scientists of ICLP and others in discharging our moral responsibility
by educating potential users of lightning protection devices.
Being a little person with very limited means, I cannot respond to every false
claim being made. My voice and those of others like me will often be drowned
by the high pitch propaganda of the merchants who are putting caviar on their
tables from the sale of those ineffective lightning protection devices. Again,
it is the duty of the potential victim of those merchants to listen harder and
try to get our message to him or her. For in the end, neither I nor any one
like me loses anything when one more fool buys those devices.
Abdul M. Mousa
6911 Southpoint Drive (A03)
Burnaby, BC V3N 4X8
Tel.: (604) 528-2328 (work)
Fax: (604) 528-1883
Response No. 12
I am finding the discussion of your recent lightning story most interesting.
The one point that I have observed is that none of the lightning protection
standards really address the reliability and resistance of the grounding
electrode system. In NFPA 780 and the LPI 175, there is mention that low
resistance is desirable, but not really defined in terms that I can apply in
the field. Perhaps this is part of the problem with determining the
effectiveness of either NFPA 780. We have been involved with many sites that
have installed lightning protection systems, yet they still experienced
lightning damage. The main variable at these sites has been the resistance and
depth of the grounding electrodes. Perhaps the real issue is not the
resistance value under test conditions, but rather will the grounding
electrode system MAINTAIN low resistance during a discharge event, thus
minimizing voltage potential to the protected structure?
For example we did a job in Florida where we used deep driven ground rods
(110' to 130' deep) for the grounding electrode system. Not only does Florida
have a lot of lightning, but also it has some of the highest soil resistance
of anywhere in the USA. The local electrical contractor typically used 10'
rods, however we found that even 20' rods measured over 200 Ohms! By going
deeper we were able to get the system to below 5 Ohms. This building has no
other grounding electrode system. This facility has documented 4 direct
lightning hits with no internal damage to the building or technology systems.
Our experience at this facility and 140 other locations around the USA
indicates deeper electrodes are more effective in dissipating lightning while
maintaining low resistance. I know that there are a lot of opinions that says
lightning will not conduct deep into the earth due to frequency and impedance
issues, however the results indicate the opposite.
Martin Conroy, Computer Power & Consulting
Response No. 13
I'm afraid I can't get overly excited by all the efforts to develop low
resistance grounds. The values measured are essentially made at dc (usually
under 200 Hz). Lightning is a short duration, double-exponential pulse, having
a very fast rise time. So, dynamic ground impedance (essentially, inductive
reactance) is the big player, and it is estimated to be at least an order of
magnitude greater than the value of grounding resistance. Consequently,
horrendous transient voltages are developed, despite low values of measured
Another case in point: As part of a lightning safety study I conducted for a
very large facility, we measured the lightning grounding system resistance
(three-point, fall-of-potential method) from the tip of each of the 108
lightning rods to "true earth" some 700 feet away. From a dc stand
point the facility appeared "bullet proof." However, RF testing
revealed that this gigantic, reinforced concrete structure---with all of its
lightning protection hardware in place and properly installed---was Swiss
cheese. Although the interior would never experience the direct effects of a
strike, enough energy would be conducted inside to cause problems with
R.T. Hasbrouck, EE, PE (Control Systems)
Response No. 12
Lightning recently struck a large oak tree 20ft. from the corner of my home.
It discharged into one of the roots of the tree, which obliviously was in
contact with my buried phone cable and TV cable. The lightning entered the
home thru the phone line and cable line. It was of sufficient strength that it
burst the grounding blocks for the phone and cable in half at the point they
were attached to the house. I suffered damaged electronic equipment throughout
the home in addition to burnt wires/connections to the phones and my hardwired
smoke detector. Several circuit breakers in the home popped but power to the
home did not go off. I had damage to numerous appliances and equipment but
other equipment in the home was not damaged. Devices such as my electric
garage door openers, TV, VCR's, Nintendo set, etc. were rendered inoperative.
My question is, what causes this damage to mostly the electronic equipment. Is
this magnetic pressure? Your articles speak of "acoustic shock
, could this cause the above-described damage? If a LPS (lightning rods) were
installed at my home, would I still be subject to this magnetic pressures and
acoustic shock wave effects if I suffered another lightning strike?
Thank you for any assistance you can provide.
Response No. 15
What causes damage to the electronics is always an electric current pulse
generated by induction of the strong electromagnetic field generated by the
lightning into any conductive body/object like wires, etc. Obviously in order
to create a current the circuit shall be "closed" respect to the
voltage generator (equivalent circuit). Obviously, especially on the mains
service, the circuit always find a closure and therefore a current can travel
throughout a determined path (normally the less inductive path), thus, if the
value of this current is high enough to create a damage (blow-up, fusion of
wires, etc.) it does.
The solution is:
1- A good and professionally designed grounding system (adequate section of
the ground wires, shortest possible ground link, etc).
2- The use of dedicated SPD (surge protection devices) on any of the
"entrance" channel to the house, i.e. mains, telephone, external TV
antennas, data line, etc.
If your house is located in a relatively high-risk area, I strongly recommend
you implement the above techniques, just to avoid the next damage and
consequential risk also to the inhabitants.
The cost of this implementation, just to give you an idea, would be one tenth
or less of the damages cost you suffered.
Carlo Donati, Sittel - Rome, Italy
Write to Mike Holt - Mike@MikeHolt.com
Courtesy of Electrical