What Is a Security Bag? Tamper-Evident Bags Explained

Security Bag A tamper-evident bag used for cash, documents, pharmaceuticals, electronics, or high-value goods.

Security bags provide a visible record when someone attempts to open, alter, or reseal the package. They are built with materials and closure systems that reveal tampering (void patterns, destructible film, or sequential seals), and they are sized and specified to match the item class they protect—cash and coin sacks differ from pharmaceutical blister-bag systems or evidence bags used by law enforcement.

Why Security Bags Matter

Security bags reduce loss, help enforce chain-of-custody, and support regulatory compliance. For cash-in-transit and retail banking they lower shrinkage and provide accountability at tills and during armoured-car pickup. In pharmaceuticals they help meet Drug Supply Chain Security Act (DSCSA) requirements by protecting product integrity during distribution. For electronics and other high-value goods they deter theft and protect evidence if a claim or inspection is required.

Common Types And How They Work

• Tamper-Evident Adhesive Closure: A peel-and-seal flap that leaves a printed void message or adhesive residue when opened.
• Destructible Film Bags: Thin, brittle plastic that tears into pieces if someone tries to remove contents intact.
• Zip-Strip Or Tamper Tape: A reusable zip with a secondary tamper tape that shows evidence if cut or peeled.
• Sequentially Numbered Bags: Bags printed with unique serial numbers or barcodes to match contents to manifests and logs.
• Combination Seals: Bags that combine seal types with printed instructions and space for signatures or documentation.

Materials And Construction

Material choice balances durability, visibility of tampering, and cost. Common constructions include multi-layer polyethylene, polypropylene with void-print layers, and laminated films that delaminate on attempted opening. Clear windows and writable panels allow scanning and annotations without breaking the seal. For pharmaceuticals and regulated products, materials must also protect against moisture and contamination.

How Security Bags Support Chain Of Custody

Chain-of-custody means each custody transfer is documented so responsibility is traceable. Security bags support this by combining unique identifiers, tamper-evident closures, and documentation space. When used correctly, receiving staff verify serial numbers, inspect seals, and log the transfer. Video capture at handoffs coupled with the bag's tamper evidence strengthens legal defensibility of the chain.

When To Use Security Bags Versus Other Packaging

• High-Theft Goods: Use security bags for high-theft SKUs during picking, staging, and outbound consolidation.
• Cash Handling: Always use numbered security bags for cash drops, deposits, and transit.
• Evidence And Controlled Substances: Use bags designed for forensic integrity with destructible materials and documented seals.
• Standard Inventory: Use standard poly bags or cartons when tamper evidence is not required to reduce cost.

Practical Considerations For Warehouse Implementation

Train staff on sealing technique and serial-number reconciliation; add barcode scanning into the WMS so the bag identifier becomes part of the order record. Store spare bags in a controlled area and log access to supplies to prevent substitution. Periodically audit sealed shipments to ensure seals remain intact during storage and transit; integrate inspection steps into receiving and returns SOPs.

Cost And Procurement Tips

• Volume Pricing: Order by the case and standardize on one or two bag sizes to reduce SKU count and cost.
• Feature Matching: Match bag features (sequential numbering, destructible film, window) to the risk profile rather than buying the most expensive option for all uses.
• Supplier Audits: Buy from manufacturers who provide material specs and quality certificates; request sample runs to validate void patterns and adhesive performance.

In short, the Security Bag is a purpose-built, tamper-evident containment method that protects value and preserves chain-of-custody. Selecting the right type, training staff, and integrating bag identifiers into operational systems turns a simple bag into an effective loss-prevention and compliance tool.