Fireproof

Area 
Prevents ignition of fires within the affected area: matches won’t light, flint won’t make sparks, and so on. Does not extinguish a fire brought in from outside the spell’s area, although such a fire would fail to ignite anything else. 
Useful anywhere that fire is a hazard (as in a gunpowder factory, for example). Any magical attempt to light a fire is at -5 to skill. This spell doesn’t resist really intense heat (as from lava or battle lasers), but it does stop guns from working!

Duration: 1 day. 
Base cost: 3. Doubled cost gives a -10 to magical attempts to light fires, and resists all heat less than star-heat. Same cost to maintain. 
Time to cast: 5 minutes. 
Prerequisite: Extinguish Fire.

Item 
An area may be permanently Fireproofed; multiply the base cost by 100. A small quantity of powdered ruby must be used (about $10 per energy point’s worth).