Definition of a Bunk Bed
The term bunk bed refers to a set of two beds placed one above the other on a wood or metal frame. Four corner posts support the upper bed. A safety railing is incorporated into the top bed frame, along with a sturdy ladder for access. Each bed within the set is also referred to as a bunk, i.e., upper bunk or top bunk and lower bunk or bottom bunk. (Generally the upper bunk is the one coveted by children.)
Bunk beds can be the same size beds stacked one over the other. A popular type is twin bed over twin bed. However different configurations can be utilized to meet different needs. A twin size can be over a full size, or even a full size over a full size. The choice is determined by the amount of bed space needed and how much floor space can be saved by using the bunk bed.
Ancient Egypt is believed to be where the concept of a bed as an actual piece of furniture began. Prior to that, people slept on the floor in make-shift piles of whatever was available: furs, plant material, or other things. The bed as we know it today evolved from there. At first, frames were complicated structures and only the wealthy could afford them. Ropes that were the original mattress support had to be tightened often. A tight rope is said to have coined the phrase, "Good night, sleep tight".
The U.S. Patent 6223363 for "bunk bed assembly" reads as follows: Abstract: A bunk bed assembly for providing a place for people to sleep. The bunk bed assembly includes a plurality of generally vertically extending elongated columns that are spaced apart and oriented in a generally rectangular configuration. Each of the columns has upper and lower ends and a transparent peripheral sidewall extending between the ends. The peripheral sidewall of each of the columns defines a bore through the column. A pair of spaced apart upper and lower bunks extend between the columns.
Use of bunk beds
Allowing two or more people to sleep in the same floor space makes the bunk bed the ideal choice in many situations. Bunk beds can be found in dorms, hostels, army bases, children's rooms, on ships, and in prison cells. Any place there is a limited amount of room to be used as a sleeping area, a bunk bed is a good solution.
Bunk Bed Safety
For maximum safety when using bunk beds, take certain precautions. Guardrails should be used on the upper bunk. Only those who are 6 years old or older should be allowed to use the top bunk. The ladder should be sturdy and secured to the frame. Children should not be allowed to use the upper bunk as a play area. Ensure the framework and mattress supports on both the upper and lower bunks are secure. Make regular checks for loose parts. Make use of a night light to make the ladder more visible in the dark.
The American Society for Testing Materials (ASTM F142792) set forth the following voluntary standard that requires, among other things, that all spaces between the guardrail and bed frame and all spaces in the head and foot boards on the top bunk be less than 3 1/2 inches. The standard also requires that bunk beds have guardrails on both sides of the top bunk.