When i was younger, i spent a year doing film company night security at a closed-down insane asylum. A big one. Crease Clinic, outside Vancouver. Still used for movie production to this day.
I was the only one there. Walking the three floors. Lobotomy room, chiller baths, prison cells with chains, you name it.
I had a small flashlight that ran off 2 AA's.
Nothing. Never saw/heard a thing that was even close to "ghost-like".
fwiw.
link:
http://crease-clinic.blogspot.ca
i did spend considerable time working in Essondale, which is as well referenced in the article.