Employer. The paperwork pretty much covered a lot of what would be required if it were a company operated office, stuff like there being smoke detectors, fire extinguisher, a basic first aid kit, that the work area was adequately sized and in an ergonomic configuration, that all exits from the work area are clear and unobstructed, no slip/trip hazards, that the lighting is appropriate, proper ventilation and adequate heating/cooling, that all electrical cords and appliances are in good order (didn't need to go to the level of 'test & tag' thankfully) and safely secured, etc.

It also stated that the company is entitled to send someone to randomly inspect my work area if they choose to... I wouldn't expect this to ever actually occur, it certainly hasn't happened for me in the last 5 years I've been working in this arrangement.

I know a number of years back there was a legal case where a big Australian company was ordered to pay the legal and medical costs of an employee who injured herself after slipping down the stairs twice in two months while working from home... so I guess it's not that crazy.