Ryan, this is EXCELLENT! As Principal Members of NEC® CMP-15 and of NFPA 99 (Health Care Facilities Code) Electrical Systems Technical Committee (HEA-ELS) and Medical Devices Technical Committee (HEA-MED), I DEEPLY appreciate that you explained that the second grounding conductor is NOT “REDUNDANT” (effectively not or no longer needed or useful; superfluous; exceeding what is necessary; . characterized by or containing an excess; serving as a duplicate for preventing failure of an entire system upon the failure of a single component). Bringing that second grounding path back around to reducing the impedance to the fault-current and stray current so that the OCPD is GREATLY sped up in operation makes it clear that the second grounding conductor essential and NOT REDUNDANT! Thank you!!! It’s worth clarifying that the 7½ feet for grounding of luminaires in 517.13(B)(1) Exception No 2 relates to the 7½ feet height of the Patient Care Vicinity defined in 517.2. Also worth noting is that “HCF” cables (Type AC-HCF and MC-HCF) are NOT mentioned in NEC®. “HCF” is a Marketing “aid” to make SPECIFYING and INSPECTING Type AC or MC cable SUITABLE for health care facilities EASIER. It IS POSSIBLE (USED to be “normal” before “HCF”) to select and receive the CORRECT Type AC or MC cable having that second grounding conductor per 517.13(B), but the “HCF” gives the specifier, the installer, and the electrical inspector CERTAINTY that the two equipment grounding paths (armor/sheath and wire-type) are in fact being furnished.
I really like that you referenced back to 517.10 and 250.118, well done. Trying to explain this to Maintenance staff and Subcontractor electricians has been difficult. Easier to let them watch your video
At a large very progressive Children's Hospital that I retired from they started what they called room a day. They tried to set aside 2 of the 550 patient rooms everyday 7 days a week. Electricians had to check every receptacle and trip GFCI'S with a tester. Also had to make sure if receltacle & switch wall plates were not engreaved with panel & circuit # we had to use tracer then P touch plates. At the same time zone mechanic replaced old ballast and replaced all lamps. They wanted every patient room to be gone thru at least once a year. Could not talk them into converting to LED'S during the down time. Even went to the trouble of adding a second TV in single bed patient rooms so kids could play playstation on 1 TV while parent watched their show on second TV.
Best pratice when installing power in patient care areas is to use quality steel set screw EMT connectors ( not crap die cast made in India garbage ) and use extra care making making ground conductor splices. Hopefully contractor will always use the correct depth mud rings on 1900 boxes so yoke on hospital grade receptacles will come in tight contact with mud ring. Always thought it would be best pratice to run a #10 guage copper wire and bond every metal stud inside an OR or within 6' of patient bed area. Thanks Ryan for another great vid.
Wonderful consideration of quality control issues. Patients and medical staff deserve the best quality control electrical installation consciously possible. Remembering that you can only expect what you inspect!!!!!
I retired from a large hospital where every OR was feed by 2 LIM panels that meadured leakage and ran an alarm around 4.7 to 4.8 milliamps. Would go into empty OR'S starting around 4 AM to perform testing LIM'S along with ground tension on the duplex receptacles and take voltage and trip alarm using a special test box. Most OR'S had 1.4 to 2 milliamp leakage current with only computers on. Have to use special wire that has low leakage. Regular type THHN/THWN insulation that is moisture, oil & sunlight resistant can never be used in an OR.
At 24:50 mention cutting the flimsy bare wire on type AC cables. We were taught to leave a 6" tail and wrap it around the cable jacket. Never know ornsaw in any instructions to just cut it off. I still can not believe that a flimsy 16 guage aluminum wire in contact with the dissimilar material steel jacket provides as good as a ground verses a 12 guage copper ground thats in a 12 guage Type MC cable. I hated seeing type AC ( Yep BX cable ) in a damp cellar feeding a heater or furnance.
Retired from a large hospital and only the what used to be called chief electrician know actually what was allowed on life safety. ( 1 example = exit luminares ) or just plain vanila emergency panels. ATS switches were programmed to have life safety to be the last lost if all the genetators shut down. Where they had 4 elevators at one location were smart enough to split emergency power to 2 ATS'S. The office that my dermatologist rents space at has hospital grade receptacles in the 2 exam/ procedure rooms.When he moved into this location 15.years ago it was my thought that this location did not need hospital grade receptacles. The only procedures he performs is using nitrogen to freeze small moles or a scapel to remive moles. Only 120 volt thing on is the luminares & desk computer. He uses a battery powered light.
Hello. Question about your mechanical and conductor ground for your dentist chair: what is the advantage for using a raceway as a ground versus just letting the guy pull two ground conductors? They both seem to be the same solution to me.
if a luminaire is 7.5ft off the ground in a patient care space, but the switch for the light is in the same room you cannot use regular mc cable for the switch leg right?
What does the NEC say about power strips for equipment in hospitals such as behind TVs for equipment that is connected to the TV . To be clear , if there are not enough wall receptacles to to handle the TV , nurse call device and video game ,is it ok to use a power strip here .
Hi Ryan so when you saying the purpose 517.13 A and B is try to create a parallel equipment grounding path for faster tripping the breaker how is that different than only need to increase the size of that EGC alone but have to have 2 paths in parallel? The resistance of that path is key isn’t it? If so a pvc with maybe #10 EGC still better (having smaller resistance) than a two parallel paths that an AC cable provided? Or maybe just design a special breaker that can trip circuit as need and this whole confusion go away? Thanks for your video.
Novice here - still confused. If the goal is to establish the lowest resistance paths (in parallel), how is two insulated copper wires not superior to an aluminum wire or metal jacket of the conduit or cable? Going back to your example of two green wires in PVC vs one green wire in AC....I understand it's code, but why is the latter better?
Think of how much surface area a conduit has. Sure, copper conducts better than steel. But a 12 AWG wire compared to a 3/4" chunk of steel? Not even close. The raceway has MUCH less resistance.
how is isolated equipment grounding receptacles isolated if it needs to be bonded to the metal box, and if it is isolated, how would that protect the equipment if there is still a ground prong and why
@@RyanJacksonElectrical i understand that, but the ground wire is bonded to the metal box, so my question is what is the purpose and how is it not counter intuitive
@@dane5167 The purpose is to have isolation because some electronic equipment can (allegedly) have issues with noise from the EGC terminal being connected to all the other EGCs and metal parts.
All seems unnecessarily complex rules. It’s either safe or not safe. Implement what is safe everywhere there are animals and humans. GFCI seems like the most important to implement.
Unfortunately, your understanding of optometry versus ophthalmology is no longer the case. There are currently four states that allow optometrists to perform surgical procedures, but optometrists are advocating for more states to allow this. There needs to be a proposal to remove their exemption in the code.
I'm certainly not an expert, butvI think by definition eye surgery is opthomolgy. A doctor who is not a surgeon might perform surgery. They're not a surgeon, but the procedure is still surgery. An optometrist that performs eye surgery may not be an opthomologist, but hecor she would be performing opthomolgy. That is just what I found via a quick search, however. I didn't perform any deep research on the issue.
@@RyanJacksonElectrical Your understanding is the traditional layperson description of an ophthalmologist as an "eye surgeon", but the fact is that in Alaska, Kentucky, Louisiana, and Oklahoma optometrists - who are only licensed as optometrists and not licensed to practice medicine and surgery as ophthalmologists are - are able to perform eye surgery. As such surgery is now included within the practice of optometry then optometrists should no longer be exempt from the code requirements. As this expansion of scope of practice is only going to progress, it should be addressed immediately if the code is intending to protect patients who have surgery performed by an optometrist within their office. theophthalmologist.com/business-profession/from-both-sides-now
Don’t care if people’s pets are electrocuted? Seems quite stupid. They are electrically conductive and their nerves are equally sensitive to currents. Also the “intended” exclusion is stupid. If there could be treatment in the waiting room, then the same standards should apply.
