As you may recall, a "new style" natural gas tanker rolled over in Raymond, NH back on May 16th. These tankers are basically four large gas cylinders stacked in a roll cage with a control panel inside the rear doors and disguised inside a normal-looking box trailer.
The trailer in this case was placarded as "Flammable" displaying UN1971 and a "Compressed Natural Gas" label.
A few months prior to this accident, NH Fire & EMS had received a statewide safety/awareness bulletin about these tankers operating in the state produced by the NH Department of Homeland Security. Long-time TSL-er and NHDHS Director Perry Plummer has approved release of that bulletin on TSL and it is below for fire, EMS & police department usage.
According to their website Xpress Natural Gas (XNG), the company involved in this particular accident is expanding operations and has customers and plants in Maine and New York. Their transport trailers double as the on-site storage tanks for their customers, and are basically hooked up and left in place, then replaced as needed.
News links, including footage of the tanks venting:
Interesting article regarding XNG's business & expansion plan:
Here's a link to a page on one of the carrier's investor's web site with photos of a transfer operation:
Above info provided by the (The Secret List) firefighterclosecalls.com