Back in 2014, we were equal parts tickled and scared by the laundry list of legal-ese health warnings that accompanied the first consumer units of Samsung's Gear VR. The HTC Vive Pre comes with a booklet of Health and Safety Warnings that's largely similar, but HTC goes a bit further in warning about some surprisingly specific potential hazards of virtual reality.

The booklet includes the kind of boilerplate warnings you'd expect before using a device that requires physical activity: users should consult a doctor if they have a heart condition and/or are pregnant or elderly. But the Vive warnings booklet goes on to urge users with "psychiatric conditions (such as anxiety disorders or post-traumatic stress disorder)" to be cautious with the device:

"Content viewed using the product can be intense, immersive, and appear very life-like and may cause your brain and body to react accordingly. Certain types of content (e.g. violent, scary, emotional, or adrenaline-based content) could trigger increased heart rate, spikes in blood pressure, panic attacks, anxiety, PTSD, fainting, and other adverse effects. If you have a history of negative physical or psychological reactions to certain real life circumstances, avoid using the product to view similar content. (emphasis added)

That's not all that surprising, considering that doctors have been using virtual reality as an immersive PTSD treatment for years. Dr. Albert "Skip" Rizzo told Ars that even rudimentary, '90s-era VR was real enough for traumatized users to feel immersed in their memories:

"When they would go through it and they would come out, I'd say, 'Bill, what did you see in there?'” Rizzo recalled. "And he'd go, 'Oh, well there was a rice paddy and Vietcong coming from the jungle and there was a water buffalo there.' Well, none of that was in the simulation... they filled in the gaps with their own memories. You can provide just enough so that people react to it as if it's real."

In the Vive's case, the simulation may be so real that HTC is worried you'll forget that virtual objects can't actually support your weight. "It is important to remember that simulated objects, such as furniture, that may be encountered while using the product do not exist in the real world, and injuries may result when interacting with those simulated objects as if they were real, for example, by attempting to sit down on a virtual chair," the booklet warns.

Watch out!

Much of the Vive warning booklet deals with all the potential hazards of walking around a room while being "blind to the world around you. In fact, HTC isn't too keen on those "blind" users trying the Vive by themselves:

"It is recommended that the product be used only while under the supervision of another person who is ready to warn of hazards that may arise while the product is being used. Examples of hazards that could arise include, but are not limited to, tangling of a cable in a manner that presents a tripping hazard, pets entering the area where the product is being used, and the user walking too close to a wall or other hazard."

While the Vive has a built-in "chaperone" system that puts up a virtual wall when you approach the borders of your proscribed "safe" zone, the warning booklet recommends you "do not rely on the product's chaperone system for protection." And while the play area should obviously be clear of furniture and obstacles, the headset should also not be used "near stairways, large windows, heat sources, or outdoors."

Don't plan to run from one corner of the room to the other while dodging virtual sniper fire on the Vive, either. "Move your feet slowly and carefully to avoid tripping, including on the cable," the booklet warns. "Make sure to maintain good footing. Tripping over the cable or contacting obstacles could cause injury or sustain damage."

Much like Samsung and the Gear VR, HTC warns that "the product was not designed to be used by children. Do not leave the product within the reach of young children or allow them to use or play with it. They could hurt themselves or others, or could accidentally damage the product." While HTC doesn't set a specific age limit for the Vive, Samsung says children under 13 shouldn't use its headset.

Even with older children that are "permitted to use the product," HTC urges parents to "monitor them closely for any negative effects during and after their use of the product. Do not allow older children to use the product if negative effects are observed. Adults should also ensure that older children avoid prolonged use of the product."

HTC's warnings list doesn't put as much focus on potential nausea as Samsung's. Still, the Vive booklet warns that "prolonged, uninterrupted use of the product should be avoided. It may negatively impact hand-eye coordination, balance, and/or cause other negative effects." Prolonged use may also lead to "tiredness or soreness in your muscles, joints, or other body parts." More generally, you shouldn't use the Vive "if you are sick, fatigued, under the influence of intoxicants/drugs, or are not feeling generally well, as it may exacerbate your condition."

Oh, and about those hand-tracking controllers: HTC says to handle them gently to avoid repetitive stress injuries. "Operate the product in a comfortable posture. Do not grip the product too tightly. Press the buttons lightly." And, much like the Nintendo Wii controllers before them, HTC reminds you to always use the wrist strap and to be wary of swinging the controller near other people.

A lot of the overzealous warnings in the HTC Vive booklet are likely just the legal department's way of covering themselves should the worst happen. But the fact that HTC felt it needed to make these specific warnings has us looking at the potential hazards of room-scale virtual reality in a new light. We'll let you know if we trip over any pets or try to sit on any virtual furniture after we set up and play with the Vive Pre over the next few days.