If you are at the front of a group of several people walking through a door, you should hold the door for the rest of the group.
If you are in such a group but not at the front, you should allow your hand to linger on the door as you walk through, to signal to the door-holder that you are willing to accept the burden of holding the door.
You are exempted from Rule 2 if (a) the hand you would use to hold the door is broken or amputated, or (b) the person currently holding the door is a purse-snatcher, and you are a cop who is trying to catch them.
You should ignore Rule 2 in situations where you are the second person in the group and there are two sets of doors. Instead, you should become the holder of the second set of doors.
In the situation described in Rule 3, Exemption (b), it is considered courteous to thank the purse-snatcher for holding the door for you.
Infants are exempted from door-holding rules, unless the infant states that they would prefer to forfeit their exemption.
In the case of automatic doors, no one has to hold them. This is because automatic doors open without anyone having to touch them, so holding them would unnecessarily complicate the process of walking through them.
If you hold the door open for a stranger who is less than 20 feet behind you and they don’t increase their speed, you are allowed to sigh audibly as they walk through (unless they are an infant).
If you are a prison warden who is leaving a cell full of inmates, you do not have to hold the cell door as you walk out. Prison inmates should not be leaving their cells.
If you are the first person to enter a revolving door, you must keep their hand on the door as is the case with more common doors in Rule 2. Once you have passed through, you do not have to continue holding the door. In fact, this will make it harder for the other people to go through the door so it is strongly discouraged.
If you are a host on a game show where a group of contestants are guessing which door a prize is behind, you do not have to hold the doors open unless each door has a second door behind it, meaning you will have to hold the first doors open so that they can point to the second doors when choosing to open them.
Only even rules apply to trapdoor situations, only the second half of those rules apply to revolving trapdoor situations, and only rules divisible by four apply to automatic revolving trapdoor situations.
If you are invading a castle and are at the front of a line of soldiers who have just succeeded in breaking down the front door, it is your responsibility to clear any corpses away from the door before charging through it.
Rule 13 is especially important if the castle has revolving doors (unless the corpses are those of infants, which are usually too small to impede the movement of the door).