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Formic Acid Storage — Silage, Leather, Textile & Feed Tanks

Storing Formic Acid? Start Here

Formic acid is a versatile chemical used in agriculture, leather tanning, and textile dyeing. It's particularly popular in dairy farms for preserving silage. If you're considering storing formic acid, it's crucial to understand the concentration you'll be handling. Whether it's 20%, 50%, or 100%, each concentration has its own storage requirements.

Can you store it in a poly tank?

Yes, you can store formic acid in a high-density polyethylene (HDPE) tank. This is true for concentrations of 20%, 50%, and even 100%. However, for 100% concentration, you need to be more cautious with fittings and gaskets—Viton gaskets are a must, and PVDF fittings are recommended.

Watch Out for Fumes

Formic acid can release fumes that are harmful if inhaled. If you can smell a sour-pickle odor, you're likely above safe exposure levels. Ensure that tanks are properly vented, especially indoors, to prevent dangerous fume buildup.

The safety that actually matters

  • Always use Viton gaskets to avoid leaks.
  • Ensure proper ventilation to manage fumes.
  • Check tank fittings and gaskets regularly for wear.

Common questions

Can I use a standard water tank for formic acid?
No, you need to replace EPDM gaskets with Viton ones for formic acid storage.
What should I do if I smell formic acid?
Increase ventilation immediately and check for leaks.
Is HDPE suitable for all concentrations of formic acid?
Yes, HDPE is suitable, but ensure the right fittings and gaskets are used, especially for 100% concentration.

Formic Acid storage tanks from OneSource

For formic acid storage, specify HDPE rated to specific gravity 1.9. Verified, compatibility-matched options:

Confirm chemical compatibility and a ZIP freight quote with our team at 866-418-1777.

Storing a corrosive acid? Material of construction is everything.

Acids attack the wrong metals fast. These vendor-neutral guides help you match resin, liner, and containment to your acid and concentration.

Explore: FRP & Fiberglass Tanks  ·  Double Wall Tanks  ·  Chemical Compatibility

Sources & References

All compatibility ratings, hazard classifications, and chemical identifiers on this page are sourced from authoritative third-party publications. Verify against the original references before final specification.

  1. PubChem Compound Database — entry for Formic Acid (CID 284, CAS 64-18-6). pubchem.ncbi.nlm.nih.gov. National Library of Medicine / NCBI. Canonical chemical-identity reference.
  2. Snyder Industries Chemical Resistance Recommendations — system-of-construction guidance for polyethylene chemical-storage tanks at industrial ASTM 1.9 SG design rating. SNY-3041 Chemical Resistance Chart. Snyder Industries, current edition. Resin + fitting + gasket + bolt MOC matrix.
  3. Equistar Technical Tip — Chemical Resistance of Polyethylene — LDPE / MDPE / HDPE rating chart by concentration and temperature, distributed by Enduraplas. enduraplas.com (PDF). Equistar polyethylene resin chemical-resistance data, distributed via Enduraplas.
  4. NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response. nfpa.org. NFPA 704 'fire diamond' health/flammability/instability/special-hazard rating system (0–4 scale).
  5. UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS), current revision. unece.org/transport/ghs. GHS pictograms, signal words, and H-statement codes referenced in this guide.
  6. ASTM D1998 — Standard Specification for Polyethylene Upright Storage Tanks, current edition. astm.org. Cited as the design-specific-gravity standard (typically 1.9 SG) for industrial chemical-service polyethylene tanks.
  7. NIOSH Pocket Guide to Chemical Hazards — occupational exposure limits, PPE, and IDLH data for Formic Acid. cdc.gov/niosh/npg. CDC / NIOSH chemical-specific occupational-safety reference.

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