Hi, just made these bunk stairs for my 5 yoa.
They are about 5ft in length 2x4s and the steps are 9 1/2 inches wide. Maybe not good for a large child or adult but seems much safer for my son.
I used no skid 3m tape on the steps and added a lock to the top left rail to keep the steps from sliding on the rail. I also checked that bathroom/oven/fridge doors will open without striking it. The top arms also latch onto the bunk rail with an angle iron attachment.
Edit: Would "ladder" be a better term?