According to the Fallout Wiki one must be sitting to wait in the game. In previous Bethesda games you could just wait by standing in a location unless involved in a few situations like combat or dialog. Since you might be in an area doing something that is time sensitive and have no way of finding a bed to rest, you just need to find a place to sit and you can wait. To wait, you have to sit and then bring up the wait menu. On PC, it is reached by hitting 'T'
The power armor radiation gauge simply gives you an idea of what radiation is present in the surrounding environment.
It's important to be aware that, while certain things like power armor and hazmat suits greatly reduce radiation damage, nothing will completely negate all rads. If your Geiger counter is clicking, you're probably taking some amount of radiation damage.
So, this provides you two things:
- General awareness of when radiation damage is being taken.
- An idea of where not to step out of your power armor. (Unless you're wearing a hazmat suit underneath.)
Another thing to be aware of is that damage and max HP reduction from rads is not based on static values in the same way most other damage is. Each rad absorbed takes out 0.1% of your maximum health, regardless of how high or low your natural maximum HP value is.
Rad absorption that's displayed in a numeric form is generally in terms of "rads per second". The greatest available radiation resistance (such as what you can get with power armor) reduces most sources of radiation to "<1" rads per second.
This means you'll usually have somewhere north of 16 minutes and 40 seconds worth of survival time, before you'll have to use Aids or die, while the Geiger counter inside your power armor is clicking away. Certainly, this should be more than enough for most scenarios. But it's still important to be aware that it is a finite period.
One particularly annoying bit about the power suit's radiation gauge however is that it doesn't actually show you how much damage you're taking. Usually, it's extremely low ("<1 rads") but it would be nice to actually see that value so you can be certain.
The suit's HUD also doesn't give you a clear indicator of how much of your maximum health is currently unavailable due to radiation damage already taken. (Well, apparently there is an indicator but it's really easy to miss.) This can be particularly annoying when you are trying to judge how to effectively use your Aids to restore available HP or remove absorbed radiation.
To work around these limitations, you can go into VATS at any time by holding the normal VATS button for a half-second or so. (This works in and out of combat, regardless of whether there's anything around that can be targeted.) There, you'll see the normal health bar and radiation indicators as appropriate.
Best Answer
Well Rested is a temporary perk that gives you a 10% XP bonus for a period of time. The wiki lists this period as being 12 hours. You can see the perk on the perks page in your Pip-Boy.
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