Difficult for me to understand what is the true intent since the 2nd link only includes a snippet of one version of the bill and states it's an amendment to definition of the original 1970's bill. I suppose the Feds are looking to standardize park models and certain styles of RVs to conform with housing standard norms. Prolly useful in areas prone to hurricanes and tornadoes yet I need more info to not guess. Should this law's definition not have been updated since the early '70's it's prolly about time to do so. Lots of RV innovations since then.