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Marine Lightning Protection


Consulting services

We offer consulting services for:

·          analysis and recommendations for specific systems, including connections and use of fittings as lightning conductors ($125 per hour);

·         analysis of lightning damage & effects or electrical effects in water ($170 per hour) (not litigation);

·         expert witness testimony, forensic investigation, and scientific analysis concerning high voltage, or any aspect of lightning, lightning locations, lightning damage, lightning protection, or lightning legal matters, especially on or near water ($200-$300 per hour).

System designs

Our designs for lightning protection systems use the National Fire Protection Association Standard 780 (NFPA780-2011) as a reference. This mandates multiple grounding electrodes for grounding and recommends peripheral placement of air terminals. There are also specific requirements for connections. Since Dr. Thomson was the first scientist to question the basis for the previous standard, and was also the prime author for the standard rewrite, including the new derivations, we are uniquely qualified to design systems that conform to the best science available.

Consulting Agreement

Terms and conditions for consulting services can be downloaded here.   Please call Dr. Thomson at +1 352 373 3485 or email him before executing the agreement.  There is no charge for the initial consultation.  However, since system estimates require an in-depth analysis of the particular customer and vessel requirements, we regret that cost estimates and system recommendations require a deposit to cover the time involved. If sending an email, please include a brief account of the project and one or two relevant images.

Consultant experience

The consultant is Ewen M. Thomson, Ph.D., who is also CEO of Marine Lightning Protection Inc. Author of a 1991 IEEE paper  concerning the US lightning  protection code that was responsible for the rewriting of that code by NFPA and ABYC,  his 23 minute video  "Lightning Protection of Sailboats"   is used by the US Power Squadron in their courses on boating  safety.   In addition to  his work on boat protection, his research interests while at the University of Florida spanned the spectrum from development of  fundamental electromagnetic theory  to design and implementation of experimental systems for lightning research. His multiple-station wideband electric field  system at Kennedy Space Center uses some of the same principles as those used in the National Lightning Detection Network. In fact, one of his UF contracts concerning lightning location was funded by Global Atmospherics Inc., that was subsequently acquired by Vaisala who now controls this network. His teaching experience included undergraduate physics,  introductory electric circuits, and  electromagnetics at both undergraduate and graduate level.  Since devoting full time to MLP he has concentrated on techniques and products for lightning protection of boats.

Coming from an academic background as a lightning researcher and teacher for about three decades, his work for MLP has included projects that have afforded him hands-on experience in the marine industry, such as:

·         design and fabrication of all MLP products in particular the innovative SiedarcTM electrode;

·         involvement in standard rewriting for ABYC and NFPA;

·         panelist at IBEX;

·         collaboration with manufacturers such as Mirage Manufacturing and Southern Spars, and designers such as  Radford Design, on systems incorporating SiedarcTM electrodes.

Other disputes have been resolved after application of his understanding of the relevant physical principles and his forensic analysis of actual damage and effects arising from lightning strikes:

·         After a criminal investigator in the Missouri State Water Patrol suspected foul play when investigating a death on a small boat, Dr. Thomson examined lightning location data and damage on the boat to conclude beyond a reasonable doubt that lightning was the probable cause of the boater's death.

·         In the case of M/V Destination Nowhere, investigation of hull lightning damage revealed multiple layers of delamination and much more extensive damage than was originally indicated. The client's disputed insurance claim was paid in full

.·         Multiple puncture holes in S/V Millennium Magic, were assessed to be just a small part of the possible overall hull damage. The client's insurance claim was paid in full.

·         Contrary to an original assessment that hull holes in S/V Chessie were the result of osmosis, a novel test developed for free carbon showed that lightning was the cause, and the client prevailed in his claim against the insurance company.

As an expert witness in legal proceedings, Dr. Thomson has been involved in the following cases:

·         Graham vs. ENSCO, 2003-2005, Galveston Division, Texas , analyzed lightning strike data obtained by the National Lightning Detection Network and weather radar data to pinpoint storm locations at the time of a lightning injury on oil rig, (deposition April 6, 2005 ).

·         Travelers Insurance vs. Lightning Prevention Systems, 2003-2006, Harrison County , Mississippi , insurance claim for boat damage from lightning to sailboat with dissipator, (no deposition).

·         Curry vs. Coast Electric, 2004, Harrison County , Mississippi , review only for power line injury, (no deposition).

·         MET Construction vs. Altel, Miami, Florida, 2001-2002, review only of lighting damage to structure, (no deposition).

·         Inquest , Ontario , Canada , concerning lightning as a factor in deaths of two sailors in Fujinon 300 sailboat race in Lake Ontario , 1992

·         Hillsborough County vs. EPA, 1990-1991, simulation of EMF from power lines, (deposition).


Consultant vitae

Ewen McKenzie Thomson  
3215 NW 17th Street Gainesville   Florida   32605-2511   Phone & FAX: (352) 373-3485   E-mail:

Biographical  Married ,  New Zealand citizen,  US citizen

Education  Ph.D., Electrical Engineering, University of Queensland , Australia , 1985;  Thesis:  Lightning in Papua New Guinea                     M.Sc. (Honors), Physics, University of Auckland, New Zealand, 1973;  Thesis:  RF Characteristics of Lightning
                    B.Sc., University of Auckland, New Zealand, 1971

Employment  2001- present  President & consultant, Marine Lightning Protection Inc.
1986- 2003 Associate Professor in Electrical Engineering, University of Florida
1985-1986 Assistant Professor in Electrical Engineering, University of Florida
1982-1984 Provisional Visiting Assistant Professor in Electrical Engineering, University of Florida
1981-1982 Research Assistant in Electrical Engineering, University of Florida
1978-1980 Lecturer 1, Physics Department, University of Papua New Guinea, Papua New Guinea
1974-1977 Senior tutor, Physics Department, University of Papua New Guinea, Papua New Guinea
1973 High School Teacher, Science Department, St. Peters College, Auckland, New Zealand    

Courses taught at University of Florida Circuits I (EEL3111), Circuits for non-EE majors (EEL3003), Electromagnetic Fields I & II (EEL3472, EEL3473), Lightning (EEL5490), Electromagnetic Fields and Applications I & II (EEL6486, EEL6487)

  Major Research Projects

1. Lightning protection of boats   Promoting lightning protection of boats through IBEX, workshops, and web pages (no longer active) and  Developing alternative theory to existing ground resistance to explain and predict sideflash formation. Earlier work was based on a resistive model for ground resistance and resulted in a video and publication directed at the lay person. Furthering the science and developing innovative products for lightning protection in the vicinity of water.

  2. Electromagnetic theory Extension of fundamental EM theory (Thomson, 2000; Thomson, 1999; Thomson, 1985; Thomson et al.,1985) applied to lightning modeling.  

3. Models for sources of dE/dt  Analyzing data obtained with the Kennedy Space Center multiple station wideband electric field system (MSWEFS) to develop physical models for the sources of dE/dt. The experimental design, described in Thomson et al. (1994), followed earlier systems; (i) for measuring horizontal electric fields (Thomson et al., 1988a,1988b); (ii) for investigation of lightning characteristics in Papua New Guinea (Thomson, 1980a; 1980b; 1978), and; (iii) for testing a design for a ground flash counter (Clegg and Thomson, 1978)  

Research Funding Summary at University of Florida
   Co-principal Investigator (with PI M.A. Uman) on NSF, NASA, DOE, and DNA grants totaling $M1.044, 1983-1988
   Principal Investigator on AFOSR, NSF, NASA, and Sea Grant grants totaling  $M1.475 1988 - 2000  

Publications and presentations
a. Reviewed
   Schueler, J. R., and E. M. Thomson (2007), Improving lightning location goodness of fit by compensating propagation effects of stratified ground, Radio Sci., 42, RS5009, doi:10.1029/2007RS003639.
, J. S. and E.M.Thomson, Estimating ground conductivity and improving lightning location goodness of fit by compensating propagation effects, submitted to Radio Science, June 2004, under revision.
   Thomson,E.M., Exact Expressions for Electric and Magnetic Field from a Propagating Lightning Channel with Arbitrary Orientation, J. Geophys. Res, 104, no.D18, 22293-22300, 1999.
   Thomson,E.M., Location of sources of radiation using a weighted hyperbola technique, NASA Tech. Briefs, 22, 64, 1998.
   Medelius, P. J., Y. Yariv, E.M. Thomson, and S. Davis, Frequency and phase compensation in a pulse transmission system, 21, 54, NASA Tech. Briefs, 1997.
   Thomson, E.M., P.J. Medelius, and S.Davis System for locating the sources of wideband dE/dt from lightning, J. Geophys. Res., 99, No D11, 22.793-22,802, 1994.
  Thomson, E.M., Lightning and sailboats, SGEB-17, Florida Sea Grant College Program Publication, 1992..
  Georgiadis, N., M. Rubinstein, M. A. Uman, P. J. Medelius, and E. M. Thomson, Lightning-Induced Voltages at Both Ends of a 448-m Power Distribution Line, IEEE Trans Electromag. Comp., 34, 451-460, 1992.
   Thomson, E.M., A critical assessment of the US code for lightning protection of boats, IEEE Trans. Electromag. Comp., 33 (2), 132-138,1991.
   Rubinstein, M., A.Y. Tzeng, M.A. Uman, P.J. Medelius and E.M. Thomson, An experimental test of a theory of lightning-induced voltages on an overhead wire, IEEE Trans. EMC, 31 (4), 376-383, 1989.
   Bils, J.R., E.M. Thomson, M.A. Uman, D. and Mackerras, Electric field pulses in close lightning cloud flashes, J. Geophys. Res., 93, 15,933-15,940, 1988.
   Thomson, E.M., P. Medelius, M.A. Uman, A remote sensor for three components of transient electric fields, IEEE Trans. Ind. Electr., 35, 426-433, 1988a.
   Thomson, E.M., P.J. Medelius, M. Rubinstein, M.A. Uman, J. Johnson, and J.W. Stone, Horizontal electric fields from lightning return strokes, J. Geophys. Res., 93, No. D3, 2429-2441, 1988b.
   Thomson, E.M., A theoretical study of electrostatic field wave shapes from lightning leaders, J. Geophys. Res., 90, 8125-8135, 1985.
   Thomson, E.M., Uman, M.A., Beasley, W.H., Speed and current for lightning stepped leaders near ground as determined from electric field records, J. Geophys., 90, 8136-8142, 1985.
    Thomson, E.M., Galib, M.A., Uman, M.A., Beasley, W.H., Master, M.J., Some features of stroke occurrence in Florida lightning flashes, J. Geophys. Res., 89, No. D3, 4910-4916, 1984.
   Thomson, E.M., Characteristics of Port Moresby ground flashes, J. Geophys., Res., 85, 1027-1036, 1980a.
   Thomson, E.M., The dependence of lightning return stroke characteristics on latitude, J. Geophys. Res., 85, 1050-1056, 1980b.
   Thomson, E.M., Photoelectric detector for daytime lightning, Electronic Letters, 14, 337-339, 1978.
    Clegg, R.J., and Thomson, E.M., Some properties of EM radiation from lightning, J. Geophys. Res., 84, 719-724, 1979.
   Thomson, E.M., Ground currents in Port Moresby lightning, Science in New Guinea ,5(2), 67-79, 1977.    Thomson, E.M., Daytime photography of lightning, Science in New Guinea ,5(2), 79-85, 1977.  

b. Video coproduced
Thomson,E.M., Lightning Protection of Sailboats, Sea Grant, 23 minutes, 1992.

c. Conference and trade show presentations

   Thomson, E.M.  Grounding lightning to water, Florida Region Meeting, Society for Accredited Marine Surveyors, Fort Pierce , Florida , 2005.   
    Thomson,E.M.  Lightning-Damage Assessment & Repair, International Boating Exposition (IBEX) , Miami , Florida , 2003
Thomson, E.M., Sideflash initiation from shipboard conductors, ULPA/LPI conference, Destin , Florida , 2003.
   Thomson,E.M.  Lightning Protection, IBEX , Miami , Florida , 2001.
   Davis, S.M., and E.M. Thomson, Lightning subsequent stroke producing new terminations to ground, 11th International Conference of Atmospheric Electricity, Guntersville, Alabama, June 7-11, 1999.    Thomson,E.M.  Lightning Protection: Fact or Fiction? ,IBEX , Miami , Florida , 1999
   Thomson, E.M. and S. Davis ,  Waveshapes in multiple station dE/dt from lightning, AGU Fall Meeting, San Francisco , 1995.
    Davis , S. and E.M.Thomson, Reversal effects in multiple station dE/dt from lightning, AGU Fall Meeting, San Francisco , 1995.
    Schueler, J.R., and E.M.Thomson, Conductivity effects in dE/dt waveshapes from lightning, AGU Fall Meeting, San Francisco , 1995.    Thomson, E.M., and P. J. Medelius, The Effect of a Propagating Lightning Source on the Waveshapes of Narrowband VHF Radiation, AGU Fall Meeting, San Francisco, 1992>
   Medelius, P.J., E.M. Thomson, and J. Pierce, E and dE/dt waveshapes for narrow bipolar pulses in intracloud lightning, Proceedings, International Conference on Lightning and Static Electricity, Cocoa Beach, 1991.
   Thomson, E.M., and P.J. Medelius, A system for mapping sources of VHF and electric field pulses from in-cloud lightning at KSC, Proceedings, International Conference on Lightning and Static Electricity, Cocoa Beach, 1991.
   Medelius,P.J. and E.M.Thomson, Multiple station wideband lightning electric field measurements, American Geophysical Union Fall Meeting, San Francisco, 1991.
   Rubinstein,M., M.A.Uman, E.M.Thomson, and P.J.Medelius, Voltages induced on a test distribution line by artificially initiated lightning at close range: Measurement and theory, 20th International Conference on Lightning Protection, Interlachen, Switzerland , 1990.   Thomson, E.M., Inadequacies in the US code for lightning protection of boats, 1989 International Conference on Lightning and Static Electricity, Bath , UK .
   Thomson, E.M., Radiation field from an in-cloud lightning process with arbitrary orientation, American Geophysical Union Fall Conference, San Francisco, 1987.
   Thomson, E.M., P. Medelius, M. Rubinstein, M.A. Uman, J. Johnson, and J.W. Stone, 1985. Horizontal electric fields from lightning return strokes in 10th International Aerospace and Ground Conference on Lightning and Static Electricity, Paris, June 1985, pp 167-173, available from Les Editions de Physique, BP112, 91944 Les Ulis Cedex, France.
   Thomson, E.M., A comparison of the electrostatic component with the full electric field change from lightning leaders and continuing currents, Vllth international Conference on Atmospheric Electricity, Albany, New York, June, 1984.
   Uman, M.A., E.P. Krider, P.L. Rustan, B.P. Kuhlman, J.P. Moreau, E.M. Thomson, J.W. Stone, and W.H. Beasley, Airborne and ground based lightning electric and magnetic fields and VHF source location for three nearby lightning flashes, International Aerospace and Ground Conference on Lightning and Static Electricity, Ft. Worth , 1983.
   Thomson, E.M., A. Enayatzadeh and M.A. Uman, Horizontal electric field measurements from lightning, Trans. Am. Geophys. Union , 64, 662, 1983.
   Thomson, E.M., and D. Mackerras, A method of characterizing lightning in terms of the impulsiveness of the charge transfer processes, in Ruhnke, L.H., and J. Latham (eds), Proceedings in Atmospheric Electricity, pp 360-364, Deepak Publishing, Virginia, 1983.
   Thomson, F.M., W.H. Beasley and M.A. Uman, Stepped leader current and velocity near ground, Trans. Am. Geophys. Union , 63, 891, 1982.
   Thomson, E.M., J.W. Stone, M.A. Uman, and W.H. Beasley, Location of lightning sources at VHF using cross correlation techniques, Trans. Geophys. Union , 62, 880, 1981  

c. Articles in non-reviewed trade magazines and journals

   Thomson, E.M., "A new concept for lightning protection of boats: protect a boat like a bulding", Boat US Exchange, October, 2007.
   Thomson, E.M., "Lightning protection", Letter, Professional Boatbulder,88, 4-6, April/May 2004   


   Method and apparatus for lightning protection, USPTO 6,708,638 a technique for lightning grounding that utilizes proactive spark initiation from electrodes.


Marine Lightning Protection Inc.

3215 NW 17th Street
Florida 32605
Phone: +1 352 373-3485    Email:    URL: