This is the device Ohio teacher John Freshwater was using to shock students and brand them with crosses: A BD-10A high-frequency generator tester for leak detection, from Electro-Technic Products, Inc.:
BD-10A high frequency generator tester leak detector, from Electro-Technic Products. “BD10ASV OUTPUT: 10,000-50,000 volts at frequency of approx. 1/2 megahertz. Power 230 V, with a momentary ON/OFF switch”
As described at the company’s website:
- Model BD-10A is the standard tester
- Model BD-10AS features a momentary ON/OFF switch
- OUTPUT: 10,000-50,000 volts at frequency of approx. 1/2 megahertz
The company also offers a line of instruments for teaching science — notably absent from that part of the catalog is this shocking device (literally).
Generally, this tester should not produce serious injury, even when misapplied. Standard middle school lab safety rules would suggest that it should never be used to “test” a human for leaks. Such voltages are designed to produce sparks. Sparks do not always behave as one expects, or hopes. High voltages may make cool looking sparks, but the effects of high voltage jolts differ from person to person. It may be harmful.
“We have instructions to warn people that it’s not a toy,” said Cuzelis, who owns Electro-Technic Products in Chicago. “If this device is directed for seconds (on the skin), that’s a clear misuse of the product.”
Cuzelis said he is not aware of anyone seriously hurt with the device and said that his company has never been sued for injuries.
What sort of lab safety rules did Freshwater have for other experiments?
If you discovered your child’s science teacher had this device, designed to produce high-voltage sparks to highlight holes in rubber and plastic liners of tanks, would you be concerned? If you know what should go on in a science class, you’d know there is probably little use for such a device in a classroom. It’s been described as a Tesla coil.
Tesla coils of extremely small voltages can be safe. They should be safe. But one occasionally finds a safety warning, such as this generalized note at Wikipedia:
Even lower power vacuum tube or solid state Tesla Coils can deliver RF currents that are capable of causing temporary internal tissue, nerve, or joint damage through Joule heating. In addition, an RF arc can carbonize flesh, causing a painful and dangerous bone-deep RF burn that may take months to heal. Because of these risks, knowledgeable experimenters avoid contact with streamers from all but the smallest systems. Professionals usually use other means of protection such as a Faraday cage or a chain mail suit to prevent dangerous currents from entering their body.
Freshwater was using a solid state Tesla coil, if I understand the news articles correctly. Knowing that these sparks can cause deep tissue and bone damage in extreme cases, I suspect that I would not allow students to experience shocks as a normal course of a science classroom, especially from an industrial device not designed with multiple safety escapes built in.
Freshwater had been zapping students for years.
Here is a classic photo of what a Tesla coil does, a much larger coil than that used by John Freshwater, and a photo not from any classroom; from Mega Volt:
Tesla coil in action, from Mike Tedesco
There is nothing in the Ohio science standards to suggest regular use of a Tesla coil in contact with students performs any educational function.
I offer this background to suggest that the normal classroom procedures designed to ensure the safety of students were not well enforced in Freshwater’s classrooms, nor was there adequate attention paid to the material that should have been taught in the class.
The teacher, John Freshwater, has been dismissed by his local school board. Freshwater supporters argue that this is a case of religious discrimination, because Freshwater kept a Bible on his desk.
Among the complaints are that he burned crosses onto the arms of students with the high-voltage leak detector shown above. This gives an entirely new and ironic meaning to the phrase “cross to bear.”
Cafe Philos wrote the most succinct summary of the case I have found, “The Firing of John Freshwater.” Discussion at that site has been robust. Paul Sunstone included photos of one of the students’ arms showing injuries from the schocks. He also included links to news stories that will bring you up to date.
Amazingly, this misuse of an electrical device may not be the most controversial point. While you and I may think this physical abuse goes beyond the pale, Freshwater has defenders who claim he was just trying to instill Biblical morality in the kids, as if that would excuse any of these actions. Over at Cafe Philos, I’ve been trying to explain just why it is that Freshwater does not have a First Amendment right to teach religion in his science class. There is another commenter with the handle “Atheist” who acts for all the world like a sock puppet for anti-First Amendment forces, i.e., not exactly defending a rational atheist position.
Below the fold I reproduce one of my answers to questions Atheist posed. More resources at the end.
Posted by Ed Darrell 
Millard Fillmore's Bathtub 