Disconnects in drop ceilings...if max height is 6’6” in 110.26 where is exception to allow disconnect in T Grid? Seems like the working clearances are to protect you from grounding yourself while servicing equipment. Also the job I’m on they are pushing this exception (???) to the hill with plumbing pipes obstructing the 3 foot in front of disco, which is mounted at 9’ AFF.
The conflict is that the disco must be within direct sight of the piece of equipment that it is associated with. When there are items above a drop ceiling, the disco/service switch has to be 'within direct sight'. Most of the time, it is a simple snap switch in a 4x4 box, or a disco mounted on the equipment (non-removable panel), or on a fabricated support (strut or ??)
That said, the piping within the 110.26 clearances is a no-no.
Remember, servicing is supposed to be performed by 'qualified persons'. The disco is to service the equipment safely, IF the disco requires any 'service', the qualified person should know enough to shut off and lock out the source. Hence, some of us AHJs require circuit ID on the discos.
We get into that with air handlers in a closet, pretty common since they won't let them go in the attic these days. They put the disco in the closet and there is no way it is 110.26 compliant. Some AHJs require an additional disco in the form of a lock out device on the panel breaker. The disco in the closet is for the HVAC tech and the LOTO is for the electrician. Other times they just let it slide. It all gets back to whether a disco is any harder to work on than any other switch. This is another one of those things that will start an argument at an inspector meeting.
I am in the camp that thinks 110.26 gets abused sometimes. I agree 100% that switch gear, load centers and similar equipment needs good working space and illumination but when you get out there to A/C disconnects I have to ask why it is any different than anything in a device box? In most environments simply hanging a "do not operate" tag on the breaker should suffice but a lockout kit with a LOTO lock on it is pretty idiot proof. I have seen the 6 holers in the LOTO with 5 locks in it and another 6 holer in the remaining hole with a couple more locks in it (government job).
Yes, there is some abuse of 110.26 by both some inspectors, some 'plant safety guys' and some sparkies.
The disco up above the drop ceiling, I have no issue with, in sight of the equipment served, and IDd as to the source of the feeder/branch circuit. I just completed an HVAC replacement project at a utility training center with 68 AHs all above the drop ceilings, with no issues.
As to the LOTO, yes, I have come upon both extremes, overkill, and 'where is it'. Tape is not a LOTO, no matter what you write on it. One facility has LOTO on all new installs until inspections are completed, 6 locks are common.
H2Os case is just the AHJs decision. A talk may help.