Hermetic Storage Bags & Chemical-Free Grain Storage
Seals wheat
Enter your grain quantity and bag capacity to get how many airtight hermetic bags you need — plus the part-fill in the last bag — to store grain chemical-free.
Bag up your harvest
Next: buy 100 hermetic (PICS-type) bags and seal the inner liner airtight so insects suffocate without chemicals.
Hermetic bags only work if dry grain goes in and the inner liner is knotted airtight — load at safe storage moisture and squeeze out air before tying.
Hermetic storage bags — key facts
- Bags needed
- grain ÷ bag capacity (round up)
- How it works
- sealed bag starves insects of O₂
- Chemicals
- none — purely airtight
- Common sizes
- 25 / 50 / 100 kg liners
- Pre-condition
- grain dry & clean before sealing
- Keeps for
- months — often a full season
- Reusable
- yes, if liner stays puncture-free
- Privacy
- Runs in your browser; nothing uploaded
Beat storage pests with a seal, not a chemical
Stored-grain insects can quietly destroy a tenth or more of a harvest, and the usual answer — fumigants and dusts — leaves residues and costs money each season. Hermetic bags flip the logic: seal dry grain in an airtight liner and the insects already inside breathe the oxygen away and die, with no chemical at all. Triple-layer PICS bags and cocoons make this practical from a single sack up to tonnes of grain.
This tool tells you exactly how many bags you need, the grain quantity and the part-fill in the last bag for the capacity you choose. Use it to budget your purchase before harvest and pack the store efficiently. Pair it with the Safe Storage Moisture, Grain Storage Capacity and Storage Loss tools to plan dry, pest-free storage end to end.
Buy the right count
Know exactly how many bags to purchase.
Skip the chemicals
Airtight storage kills pests with no residue.
Plan the last bag
See the part-fill so nothing is left loose.
Protect every kilo
Near-zero weight loss across the season.
Frequently Asked Questions
What is a hermetic storage bag?+
A hermetic (airtight) bag is a sealed liner — often a triple-layer PICS bag, GrainPro cocoon or similar — that traps grain in an airtight space. Once sealed, the grain and any resident insects keep breathing, using up the oxygen and building up carbon dioxide until the pests suffocate. No fumigant or chemical is needed; the seal alone protects the grain.
How are the number of bags calculated?+
Bags = grain quantity ÷ bag capacity, rounded up. The last bag is usually only part-full, so the tool shows both the total number of bags and how much grain goes in that final part-bag. For example 850 kg of grain in 50 kg bags needs 17 bags, with the 17th holding 50 kg and the rest full — or 880 kg needs 18 bags with the last holding 30 kg.
How do hermetic bags kill insects without chemicals?+
Insects, mould and the grain itself respire inside the sealed bag, consuming oxygen and releasing carbon dioxide. Within days to a couple of weeks the oxygen drops low enough and CO₂ rises high enough that insects die and mould growth stalls. It's a purely physical, residue-free method — ideal for seed, food grain and organic produce.
What grains can I store this way?+
Hermetic bags suit cereals (wheat, paddy, maize, sorghum), pulses (chickpea, pigeon pea, beans), and oilseeds, as well as seed grain. The key is that the grain is dry and clean before sealing — hermetic storage stops pest damage but cannot dry wet grain or fix mould that has already started.
How dry should the grain be before sealing?+
Grain must be at or below its safe storage moisture before going into a hermetic bag — roughly 13–14% for cereals and lower for oilseeds. Sealing damp grain traps moisture and can cause caking or mould. Dry the grain first, then fill and seal; check our Safe Storage Moisture calculator for the limit for your crop.
What capacity should I use per bag?+
Common PICS-style liners come in 25, 50 and 100 kg sizes; cocoons and bunkers run far larger. Enter the rated capacity of the bags you'll use. If you fill to the brim it's harder to seal cleanly, so many farmers leave a little headroom — use the practical fill weight you actually achieve as the capacity.
How long does grain keep in a hermetic bag?+
Properly dried, clean grain in an intact, well-sealed hermetic bag can keep safely for many months — often a full season or more — with negligible insect damage and no weight loss. Keep bags off the floor, away from rodents and sharp edges, and reseal immediately after each opening to restore the airtight environment.
Can I reuse hermetic bags?+
Often yes — quality inner liners can be reused for several seasons if they stay free of punctures. Inspect each liner for holes before refilling, since a single pinhole lets air in and defeats the seal. Store empty liners clean and dry, and keep the outer woven sack to protect the liner from abrasion and rodents.
Are the figures exact?+
The bag count is exact arithmetic for the capacity you enter; the part-bag tells you the leftover. Real-world needs vary with how full you pack each bag and how much headroom you leave for sealing. Treat the result as your purchase and packing plan, and buy a spare bag or two for the part-fill and for replacements.