In my early days working in the funeral industry we were not allowed to go home on our call nights at the funeral home, but then again this was before cell phones and pagers. We had to be there to make death calls and embalm cases as soon as they were brought into the funeral home's care.
As you can imagine, being the only embalmer for a funeral home that handled over 450 cases per year, I spent many nights alone, on call at the funeral home, or was required to come and embalm even if I wasn't on call. When you spend 4 to 5 nights per week there it becomes just like home (well almost).
With that being true most of us never bothered turning lights on at night as we moved from point A to point B, and just moved about by the residual light from the hallways or staterooms.
On one particular occasion we had been rather busy for the past few days and I was spending yet another call night there alone, in the embalming room, at 3:00 AM, embalming. The embalming room had 3 embalming tables, about 8 dressing tables and two entrance doors which were laid out in such a way that when you were using one certain table your back was to the doorway leading to the hallway, the other door of course led to the garage. This night was just like many before it, 6 or 7 people on dressing tables, 2 or 3 on the embalming tables, and I of course being the only living presence in the building (actually the entire block, as the funeral home and parking lot occupied it all).
I was in the process of beginning the embalming operation on a young car accident victim when I heard what I can best describe as a man and woman having a conversation in the hallway just outside the door. I could clearly hear the discussion, but could not determine what they were saying. Initially I thought that one of the other directors had stopped by for some reason, but then thought "surely not at 3:00 AM." As soon as I opened the door the voices stopped, and there was no one to be seen in the empty hall. Attributing it to fatigue I closed the door and returned to my task. Within 5 minutes the discussion began again. Again the discussion ceased as soon as I opened the door. Not really caring what was happening I closed the door the second time and returned to my work.
Within a couple of minutes I heard a piercing scream, as though someone were being tortured, emanate from down the hallway near the staterooms. This time I knew something was up and was determined to find out what. My first thought was that someone had fallen asleep during visitation and had just awakened to find they were alone in a dark funeral home.
I knew that I had to go let them out of the funeral home, so I started down the hall to find them. The residual light from the lamps was sufficient to check the casketed cases in the staterooms where friends had gathered just that evening, to see who it was that had screamed in such a harrowing manner. I found no one in the funeral home, and was returning to the embalming room when it occurred to me that they must have run out the nearest door. I then checked EVERY door to find that each was securely locked. Thinking that they must have had the sense to at least lock the door on their way out, I again started to return to the embalming room.
Having found on one, and all the doors locked, as I reached for the doorknob to the embalming room door, I saw the residual light from the one lamp left on in the lobby at the opposite end of the hallway seem to explode into a bright halo on the embalming room door. It was only then that I realized that no one could have left the building because the security alarm never sounded. Even with several bodies on tables there I spent the rest of the night in the embalming room where I felt safe. I never figured out what it was.
You seem to take your experiences in stride, accepting these things as the industry norm. As a person reading about these experiences I want to assure you, there seems nothing normal about it. I don't know that I have ever used the word "dread" in print, but you have certainly filled me with it. Terror, followed by a heart attack, comes to mind when considering being in a funeral home at 3:00A.M. To be there when the dead really walk, speak and scream transforms mere terror into something indescribable.
Please know I am not making disparaging remarks in any way regarding you or what you have brought to your readers. The things you have told us about your reality makes horror film screen writers appear inept. Truth clearly triumphs over fiction.