In a building where they are switching over to a fiberglass free environment due to many cases of sick building syndrome, a contractor was hired to install fiberglass free HVAC systems. After they were put in some of the employees who are fiberglass sensitive continued to have issues when the unit would turn on. When the matter was looked into they found that above the ceiling panels of the offices in question the contractor had not only installed fiberglass flex-ducts, but never taped them off leaving it exposed to the air.
This is inside another office in the same building installed by the same contractor at the same time. Notice the fiberglass exposed behind the wire and the rip in the casing, which also has fiberglass strings in it.
The casing around the new flex ducts also contained fiberglass. See the string-like material. These ducts will be removed and replaced with true fiberglass-free ducts.