Made a quick graphic with my estimates for dimensions, based off muh knowledge and this pic.
Scaffolding is made by a number of different companies, but usually abides by somewhat standard dimensions. I snagged some picks from Depot's website to give you a basic idea of the dimensions of this type of scaffolding. Obviously, this isn't the same make, but the general dimensions will be close enough between manufacturers.
These sections (I'm almost 100% sure) are the 5' x 5' H-frame. The planks can vary in length, but these are probably going to be the 7' long planks (The 5' long planks are rarely used, and these appear to be too small to say they are 10').