The figures on flammability ranges and explosive limits do not have the catastophic, unsafe effect claimed. I'm happy to report that hydrogen is transported and delivered safely thousands of times every year. And in fact many of the properties that you cite are the very things that allow hydrogen to provide benefits to energy security, the environment and our economy.
Safety? Hydrogen tanks have been drop tested, bullet tested, bonfire tested and put through tons of rigorous tests to make sure you and everyone else can handle them safety. Hydrogen cars are crash tested too. While hydrogen is flammable just like other fuels we use everyday, have no fear that you can handle hydrogen products just like you handle batteries, gasoline at the pump or even natural gas right in our homes.
In fact, many of hydrogen's properties make it safer. The tendency of hydrogen to dissipate is actually a huge benefit, because it won't pool on the ground like gasoline or propane, but rather will rise up and away so that it won't be able to catch on fire.
The hundreds of companies that are selling hydrogen products today are smart enough and have been working at this long enough to know how to make hydrogen devices that work safely.
Still unsure of hydrogen's safety? Become more familiar with the world's most abundant element by either reading about how it's being used today:
http://www.h2andyou.org
OR learning about the safety aspects at: http://www.hydrogenassociation.org/general/factSheet_safety.pdf
OR you can even take a free, short online course offered by the Department of Energy:
http://www.hydrogen.energy.gov/firstresponders.html