Design risk factors

[BG6]

The story about the Floridan couple who died should be two lessons to anyone doing a coach conversion.

First lesson:  you can't eliminate all risks.

Second lesson:  you should eliminate or reduce those you CAN.

When our rigs were in bus service, the primary risks came from outside -- collision, road hazards, etc.  The drivers were trained, the only fire danger was from the fuel, the batteries are generally placed where an axle protects them from side impacts, and the heavy objects were the pax in their seats, which were secured to the floor (the seats, not the passengers).

Look at your coach today.  You've added house batteries (which may or may not be in the same bay as your coach batteries), you've added a bunch of stuff inside, which may not be properly secured (hint:  If you can move it without using tools, it's NOT SECURED), you've added a propane system which distributes pressurized, flammable gas to various points throughout the coach, you've added water tanks, pipes, wiring, water heater, heater, counters, beds, TV, on and on and on.

Each change that you have made has made your coach less safe than it was when it left the assembly line. 

Consider the effect of a T-bone traffic collision.  Will it get your propane tanks?  Or maybe just the line that goes to the stove?  How about your house batteries -- will the damage shove a metal door across the terminals of a few hundred amp-hours of ready-to-spark . . ?

Or how about being hit hard in the front or rear?  What's going to shift?  Do you have a 20-foot-long black pipe feeding your propane, which will act like a spear and drive into the fuel tank or the engine exhaust system?

As you design your conversion, keep these things in mind.  Put bend points in any metal pipe longer than ten feet (two 90-degree elbows with a short stub between them).  Secure heavy items, use drawer locks, make as much of your plumbing flexible as possible (PEX or similar piping), if you have something which will become a spear, aim that spear where it will do the least damage or injury.

ABOVE ALL ELSE, protect the driver!  No matter what else goes wrong, the driver is the only one who can steer and stop!

The optimum is to have everything secured so well that the coach could be inverted or go end-over-end without anything coming loose, and shortened by 50% in ANY direction without releasing fuel, striking sparks, or having anything enter the passenger area.

We can't reach that optimum, but the original manufacturer came pretty close, which is the absolute best reason to do a coach conversion.  If you keep it in mind, as you design and build you will see ways to make minor improvements (such as putting your house batteries into individual, plastic battery boxes, with hot leads in plastic conduit and hot terminals in plastic boxes).

[kyle4501]

Amazes me at how so many people disrespect the amount of energy in a battery & how fast it can be released.

[BG6]

I hate to be sensationalistic, so I won't mention that I've seen where a motorcycle battery tipped over against a metal aircraft frame, welded in place, and started a fire. 

[belfert]

Reading this reminds me I never secured my batteries.  I need to secure them or ideally move them elsewhere and secure them there.