Before you specify
Frequently Asked Questions
Is the Dahle 20394 actually NSA approved?
Yes, and this can be checked rather than taken on trust. The NSA/CSS Evaluated Products List for paper shredders lists 'Dahle 20394' under Dahle North America, Inc. with a throughput rating of High, and it remained on the list as of the April 2026 quarterly update. This matters because NSA/CSS 02-01 requires both a particle no larger than 1 mm x 5 mm and the specific model being listed. A P-7 DIN rating by itself does not make a shredder NSA approved.
Can it shred staples, paper clips, credit cards or CDs?
No. Dahle rates the 20394 for paper only. The 1 x 4.7 mm cutting head is machined to very tight tolerances and metal or rigid plastic will damage it. Remove staples, clips and fasteners before feeding. If you also need to destroy optical media or cards, that is a separate machine - Dahle's 747 CS is the NSA-listed device for optical media, and the P-5 20392 on this same chassis handles cards and CDs for non-classified work.
Nine sheets sounds low. How does that compare?
For P-7 it is high. Dahle's other NSA-listed machines take four to eight sheets a pass: the 20434DS takes four, the 40334 five, and the 40434 and 40534 eight. Nine sheets of #20 bond (11 of #16) makes the 20394 the highest-capacity model in the line. Compared with a general office shredder it is still slow - the 20396 on the same chassis takes 38 sheets - but that is the cost of a 4.7 mm2 particle.
What shred bags does it take?
The bin is 50 gallons, which is covered by Dahle 20726 bags (rated for 31-55 gallon shredders, 100 bags per box). Bags do not come with the shredder. One practical note for high-security use: P-7 output is close to a powder and finds any hole in a bag, so a gusseted 1.5 mil bag is a better choice than a thin liner, and the bag should be sealed before it leaves the room.
Will legal and tabloid paper fit?
Yes - the feed opening is 16 inches, so 8.5 x 14 legal and 11 x 17 tabloid both enter unfolded when fed short-edge first. Bear in mind the nine-sheet rating is measured on letter-size #20 bond. Wider or heavier stock uses more of the cutting width and more motor torque at once, so reduce the stack when you move to tabloid or to heavier paper.
How loud is it in an open office?
Dahle rates it at 56 dB, which is quieter than the 60 dB of the P-5 20392 and the 64 dB of the P-4 20396 on the same chassis. That is roughly conversational level, so it is usable in a shared room, though a 245 lb machine on a 16-inch throat is normally installed in a records room or copier area rather than beside desks.
What is covered by the warranty?
Two years on the machine and one year on the cutting cylinders. That one-year cylinder term is the trade-off across Dahle's high-security range: the P-3, P-4 and P-5 models in the same cabinets carry a lifetime cutting-cylinder warranty, while every P-6 and P-7 model, including this one, carries one year. Budget for the cutting head as a wear item on a machine running heavy daily volume.