It was discovered that in both accidents the acetylene cylinders were insufficiently secured and were thrown from their trailer at the time of the accident.  This resulted in valves being broken off several of the tanks allowing gas to escape which then was ignited.  The resulting fire melted the valves on the remaining cylinders which also caught fire.

The NTSB proposed safety recommendations are for the Pipeline and Hazardous Materials Safety Administration and read as follows:

Modify 49 Code of Federal Regulations173.301 to clearly require (1) that cylinders be securely mounted on mobile acetylene trailers and other trailers with manifolded cylinders to reduce the likelihood of cyliners being ejected during and accident and (2) that the cylider valves, piping and finttils be protected from mulitdirectional impact forces that are likely to occur during highway accidents, including rollovers.  (H-09-1)

With what would appear to be a potential fire ball rolling down the highway, we can only hope that these new safety recommendations are implemented quickly and strongly enforced.