I have an employee who works out of an office in a different state. She has back problems and the standard office chairs aggravate them and cause her pain. So several years ago, she went through the corporate ergonomic assessment, tried several different chairs, and found one that worked for her.
Since then, HR and all related areas (like health and safety, who do the ergonomics) has been outsourced, and the people she worked with are no longer at the company. She was never given anything in writing about her chair.
Wednesday of this week, the facility manager at her office sent out an email stating that EVERYONE's chair would be replaced next week. If you were on a list that the department admin had, your chair would be left alone. Of course my employee's name is not on the magic list, so she contacted the facilities manager to ask what she could do - she's perfectly willing to try the new wonderful chair, but she'd like to keep her current chair available for a few days or a week to be sure the new chair will work.
Facilities manager told her to contact HR. HR gave her the new health and safety contact. Health and safety's advice is...try the new wonderful chair, and if it doesn't work, we'll work with you to find a new one. Which sounds great, except that if the new chair doesn't work, she's stuck with potentially several weeks/months of back pain while the wheels grind through ordering a new chair, trying it for a few days, trying another one...all of which could be saved if they'd just let her keep her current chair.
I suggested hiding it in an empty office or storeroom, but Facilities Manager has made it very clear that they will be going into all empty offices, storage spaces, conference rooms, etc, to stamp out the evil that is Nonconforming Chairs.