There are several types of Uniforms for military personnel in BSG. Different ranks, departments, and positions all have their own types of uniform clothing. With few exceptions, characters are to wear some form of accepted uniform at all times. Being out of uniform is a punishable offense.
All uniforms, unless otherwise noted, share the common characteristics of rank pins on the collar and the Colonial Insignia/Battlestar patch on the shoulder.
Duty Uniform[]
The Duty Uniform, also know as "Duty Blues" is the standard uniform for Colonial Officers. This is what you always see the officers wearing. Any commissioned officer (ensign and above) will have this type of uniform. CIC officers, the LSO, etc. wear their Blues whenever on duty. However, many other officers like pilots, gun captains, and marines do not (or are not required) to wear it while on duty in favor of another type of uniform.
If earned, an officer will also wear their flight wings on their chest.
Dress Uniform[]
Special formal occasions call for a variation of the Duty Blues known as Dress Grays. In addition to the changed color, the dress uniform is also worn untucked (and thus long) with a formal sash and belt. Some officers may wear shoulder cords and officers may also wear any military decorations they have been awarded. The Dress Uniform is also often worn with white gloves.
Flight Suit[]
Flight Suits are made of a green and brown material that creates basic life-support for the pilot (pressurized, heated, and oxygen supply in the event their craft is damaged or they must even eject). Both Viper and Raptor pilots wear flight suits. The suit is paired with a metal collar and helmet which complete the self contained life-support system.
In addition to rank, Battlestar patch, and flight wings, the flight suit is also worn with the patch of the pilot's squadron.
Gunner Suits[]
Due to their combat postings at the hull of the ship (or sometimes even in guns which technically are outside the hull) and the high chance of damage which could lead to decompression, gunners also wear life-support suits and helmets. In the event of decompression gun crews can: keep fighting if their station is functional; retreat out of their damaged section; or survive and wait for SAR in the event that they are vented into space. To distinguish them, gun crew suits are black.
Space Suits[]
Space Suits are the bulkier more industrial strength cousin of the flight suit. They are used by repair crews taking spacewalks. The flight suit is designed to keep you alive in the void long enough for someone to find you and pick you up. You just float around and try not to use up all your air. These suits are built specifically for work in harsh environments. These suits exchange limited mobility for a tougher suit with better and longer sustaining life-support. These space suits also come with more built-in features such as lights, magnetic boots, and the like to aid in repair work.
Space Suits are communal equipment rather than personal clothing. They notably lack rank and Battlestar patch.
Fatigues[]
Green Fatigues are part of every service member's wardrobe. Crew members with no other uniform (such as enlisted engineers and support personnel) wear this as their primary duty uniform. All others typically revert to their fatigues as their secondary clothing option, generally for when they are off duty.
Tan Fatigues[]
Warrant officers and some senior NCOs such as the Master at Arms have tan fatigues rather than the typical green worn by all other personnel.
Coveralls[]
Orange coveralls are the work uniform for deckhands. They are covered with reflective tape and built-in toolbelt-esque pockets. Other than those two additions, they are very much like the fatigues.
Yellow Coveralls[]
To distinguish them from the other deckhands, launch technicians wear yellow coveralls.
Battle Dress Uniform[]
The Battle Dress Uniform (BDU) is the name given to the fatigues worn by Marines. To distinguish them, marines wear black fatigues (although they may also wear the standard green when off duty).
In addition to the basic clothing, marines also are equipped with tactical vests, helmets, knee and elbow pads, communications equipment, and goggles. Marines with special duties (such as military police/shore patrol/security) may also wear an armband with white letters indicating this responsibility.
Variations[]
The standard uniform is solid black, but variations are available for different combat scenarios. The Colonial Marine Corps has camouflage uniforms for all sorts of scenarios and utilizes the digital pattern style.
Under Garments[]
In addition to the above outerwear, all military personnel are issued gray t-shirts (sleeved or sleeveless) and dark brown tank top. These are often worn together, with the tank top over-top of the t-shirt.
The only notable exception is that marines are issued solid black t-shirts to match their all black fatigues.
Other[]
There are (presumably) other less common types of uniform clothing aboard ship. An article of note actually seen in the series is what appears to be a light gray sweatsuit.
Mixed States of Dress[]
It is not uncommon at all to see off-duty personnel (or sometimes personnel doing hard manual labor) to be in states of partial dress. Typically this involves removing their shirt and thus wearing only the t-shirt/tank top combo (or perhaps just one or the other). This can be done while wearing any form of pants (duty blue, green fatigues, etc.) to make a number of combinations. For flight suits and coveralls, which are full body pieces, the tops are often opened and allowed to hang behind the wearer to create the same effect.
Civilian Clothing[]
Civilian clothing just is not worn aboard a warship. One can have a large wardrobe which can be worn freely when on shore leave, but when aboard ship the uniform is what is to be worn. One might get away with wearing civilian clothing while off-duty, especially when staying in one's quarters and not walking the ship, but even that is not an absolute certainty.