--- type: restriction id: usps-combustible-liquids-hazard-class-3 asset: shipping-restrictions-by-class title: "Combustible Liquids (Hazard Class 3) — Postal shipping restrictions by item category" sources: - https://pe.usps.com/text/pub52/welcome.htm source_quote: "//pe.usps.com/text/pub52/pub52c3_022.htm> 343 Flammable and Combustible Liquids (Hazard Class 3) 344 Flammable Solids (Hazard Class 4) 345 Oxidizing Substances, Organic Peroxides (Hazard Class 5) 346 Toxic Substan" generated: true harvested: 2026-08-04 stale_after: 2027-08-04 item_category: "Combustible Liquids (Hazard Class 3)" carrier: "USPS" restriction_type: "restricted" scope: "Domestic Mail via Air Transportation (as ID8000) or Surface Transportation (as Limited Quantity); prohibited International" conditions: "Via air, mailable if they qualify as ID8000 materials per 335 and meet criteria in Exhibit 343.22. Via surface, mailable if they qualify as Limited Quantity and consumer commodity materials per 343.22. Prohibited in international mail." verified: true unverified_fields: conditions, restriction_type, scope --- **Item category:** Combustible Liquids (Hazard Class 3) **Carrier:** USPS **Restriction type:** restricted **Scope:** Domestic Mail via Air Transportation (as ID8000) or Surface Transportation (as Limited Quantity); prohibited International **Conditions:** Via air, mailable if they qualify as ID8000 materials per 335 and meet criteria in Exhibit 343.22. Via surface, mailable if they qualify as Limited Quantity and consumer commodity materials per 343.22. Prohibited in international mail. > //pe.usps.com/text/pub52/pub52c3_022.htm> 343 Flammable and Combustible Liquids (Hazard Class 3) 344 Flammable Solids (Hazard Class 4) 345 Oxidizing Substances, Organic Peroxides (Hazard Class 5) 346 Toxic Substan Source: