The components on MD4000 single board computer run on 3.3VDC (nominal). If 3.3V are supplied directly to the MD4000 board (eliminating the DC-DC converter) then the system is intrinsically safe since sparks do not occur at that low voltage.

The power requirements for the mesh node vary between 12 - 16 W depending on the number of radios employed. The higher amperage required at this low voltage requires a connector that supports 5-6 Amps. The Intrinsic Safe  (IS) node enclosure needs to use power connectors other than the RJ45 connectors that are limited to in amp capacity.  Additionally, low voltage portable power sources are needed to power the mesh node.
 
The cell stack portable power supply shown below consists of seven 3.6VDC cells in parallel. Each cell has a capacity of 20 Amp-Hrs. The seven cell stack has an aggregate capacity of 140 Amp Hours - sufficient to power the mesh node for a 24 hour period. Note that the battery capacity is adjustable -  based on the number of cells in the cell stack. 
   
Please contact Meshdynamics for details on the connector modifications and integration with low voltage portable power sources.