The box will be bolted to the concrete floor in a detached garage. Gasoline will be in nato 5 gal jerry cans in the box. Should I drill holes in the box for ventilation or not? Thanks

Ventilation is important.

Yes that's why storage boxes on construction sites are heavy steel mesh, NO enclosed boxes! It would be a disaster waiting to happen.

Should I drill holes in the box for ventilation or not

My uneducated opinion.  Your gas should be in tightly sealed containers.  If they are vented, the gas goes bad faster.  No holes.

He's referring to storing the containers within a container. Should the cans vent any vapor into an enclosed space, you now have a bomb.

If the NATO cans are sealed, why do you think you need cabinet ventilation.

The cover closure leakage of the cabinet is sufficient for any ventilation needed.

Why inside a box inside a garage?  Non ethanol gas?

the job boxes are not vapor tight. it will breath

unfortunately ethanol gas but w/ stabilizer added.

Guys, thanks for the replys. I understand venting gas fumes but the reason I asked is that I will be using brand new nato cans as the gas containers and they seal up tighter than a ducks arse, cant smell any gas once they are shut, no leakage when cans are inverted. I am out of caution, and thanks to your replies, going to drill 1/4" vent holes in a grid pattern on each side of the box.

Also, the reason for putting the nato cans in a work box is security. The garage doors stay open a good bit when the weather is nice and jerry cans aren't getting any cheaper if they walk away.

Job boxes are great for securing tools...kinda challenging to chain down a torch head or a sawzall.

But really a job box is no more secure than a lock and chain...If a thief wants in then they will get in, or get elected and raise taxes

kaiserworks, I think you could do just as well with a chain and lock.

If you are using NATO cans that are working properly then there should be no need to drill the job box.  
IF and this a large If...one of your NATO cans should let a bit of gas out, then normal fuel handling practices should abate any  remaining risk.  

Normal practices like:
Do Not Smoke when handling fuel...Just Say No to
Control static electricity by grounding yourself and the fuel can...but oh you did that when you touched the metal job box and lifted out the NATO can and set it on the floor  

If gas vapors are heavier then air and the job box breathes only around the top edge then logic says the gas vapors would displace most of the air in the box before it ever vented out excess vapors.

I made a storage unit out of some old steel frames and wire decks used in warehouses for pallet storage.  I got all of it free but its not hard to find stuff like that cheap.  This way each level completely vents to ground level.

Factor in 'diffusion' that will dilute the vapors, aggressively.

Oh NOOOOOOO!!! That would scratch the paint on my new cans!  

Meh

Kryptonite cable then

Teh new gonna get knocked off someday anyway

Might as well make it on your terms

Not enough.

Why in the world does it matter????

I vote for venting it.

Although very unlikely, it's conceivable that simply opening the job box lid could produce a spark, due to metal-to-metal contact between the hinge pieces as they move.

Allowing gas fumes to build up is never a good situation.

If that were always true then Engineers in the marine industry would not be so up tight about boats becoming floating fuel bombs with vapors below deck and have specs that everything being "safe" to use in and around gas vapors.

To each his own, I got the cure a couple decades ago while in the ER to get some foreign object removed from my hand.  While deciding where they should cut, a guy came in burned from the waist down from a small fuel fire that started with ignited vapors.  Being summer, he was not wearing heavy clothing and what he did have on burned.  I remember that Man's agony.  In SHTF a fuel fire on you will likely be lethal and possibly burn down the building so logic says not in the building and vented.  IF in the building, why rely on luck and diffusion?  Even if he does, he still needs to make sure possible ignition sources are off the floor.  Then comes that cold winter day when you want to heat the building.  I find by being careful, when I do push my luck a bit, things turn out good.  On the other hand, we often learn from the tragic mistakes of others.

trag·ic
'trajik/
adjective
adjective: tragic

   1. causing or characterized by extreme distress or sorrow.
   "the shooting was a tragic accident"
   synonyms:disastrous, calamitous, catastrophic, cataclysmic, devastating, terrible, dreadful, awful, appalling, dismal, horrendous; fatal, deadly, mortal, lethal
   "a tragic accident"
   regrettable, shameful, terrible, horrible, awful, deplorable, lamentable, piteous, dreadful, grievous
   "a tragic waste of talent"
   antonyms:fortunate, lucky
       suffering extreme distress or sorrow.
       "the tragic parents reached the end of their tether"
       synonyms:sad, unhappy, pathetic, moving, distressing, depressing, painful, harrowing, heart-rending, piteous, wretched, sorry

I'd vent the shit out of it. Gas vapors can do some serious damage. Err on the safe side.

Prolly a good idea to vent it then...

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Google " propane cylinder cage " can be found behind every empty warehouse, make an offer to remove it for free.