FIFO (First In First Out)

Detailed Explanation

FIFO (First In First Out) is one of the foundational principles of modern inventory management. It guarantees that the oldest batch is used or shipped first in raw material, intermediate, and finished product stocks. Three main variants:

1. Classic FIFO — entry-date focused; the oldest production-date batch is used first. General food, chemical, plastic raw materials. 2. FEFO (First Expired First Out) — expiration-date focused; the batch nearest expiration is used first. Pharmaceutical, fresh dairy, meat, frozen food. 3. LIFO (Last In First Out) — last in first out; accounting-focused, rarely applied physically (prohibited for food/pharma).

FIFO implementation methods:

1. Physical rack layout — in cold storage, pallets are arranged back-to-front; new pallets at the back, old pallets pulled from the front. Gravity-flow racks (sloped rollers) facilitate this. 2. Colour-coded labelling — different colour every week/month; oldest visually recognised at a glance. 3. Barcode/RFID tracking — every pallet barcoded; WMS (Warehouse Management System) auto-allocates the oldest pallet. 4. Dated lidded containers — internal package date tracked in open packaging; oldest dates moved to the front in retail.

In cold-chain and food operations, FIFO + temperature-humidity control + continuous monitoring work as a whole. The dehumidifier keeps the warehouse ambient stable while the FIFO system guarantees product rotation. The dehumidification technology is selected by the dew point of the target condition: condensing units when the dew point is above +10 °C and the store above 15 °C, silica gel rotor units when the dew point is below +5 °C or the store below +10 °C.

Why It Matters

When correctly applied, FIFO directly affects six critical operational metrics:

1. Product quality — fresh product always goes to market, consumer satisfaction is high; old product left in storage = quality loss + returns 2. Shelf-life utilisation — with FIFO each product uses its maximum shelf life; FIFO violation forces products to be discarded pre-expiry (waste) 3. Microbial safety — long storage extends microbial risk, especially for cold-tolerant pathogens like Listeria and moulds. FIFO + ambient control is mandatory in combination 4. Regulatory compliance — EU Reg. 178/2002 (food traceability), 2073/2005 (microbiological criteria), USP <659> (pharma shelf life) all mandate FIFO 5. Inventory value loss — old stock sells below balance-sheet value; FIFO violation = inflated balance sheet + real loss 6. Recall traceability — when a problem batch is identified, FIFO + lot tracking lets affected products be quickly traced; recall is possible within hours

FIFO's critical complement is environmental control: correct ambient (temperature, dew point, RH) makes FIFO shelf-life estimates work. Example: if matured kaşar is labelled with a 6-month shelf life, this holds when the warehouse is kept at 13°C / 88% RH; but exposure to 18°C / 75% RH spoils the product in 3 months, the FIFO assumption collapses, and the product reaching the customer is spoiled.

For this reason FIFO + continuous ambient monitoring + WMS integration is the standard combination in modern food/pharma plants. The NKT - Climate Track system continuously logs warehouse ambient, generates deviation alarms, and provides the foundational data for the FIFO system.

Practical Example

A FIFO + climate control scenario in a kaşar cheese distribution warehouse:

Facility data: • Cold storage volume: 2,400 m³ (40 × 20 × 3 m) • Storage condition: 13 °C / 88% RH (dew point ≈ 11 °C) • Product: matured kaşar, 6-month shelf life • Rotation rate: 4 weeks

Typical problem: • Manual FIFO, pallets get mixed up • In summer, warehouse temperature and humidity drift out of the target band • Product loses quality before reaching its labelled shelf life; rind mould appears

Dehumidification technology selection: • The dew point of the target condition is ≈ 11 °C, within the efficient range of condensing units (≥ +10 °C); a condensing CD series unit can be used. • However, as the store is at 13 °C, below 15 °C, the unit's capacity is lower than the catalogue value; selection is made with the low-temperature capacity curve (CD series operating range +10…+40 °C). • If the same store were held at 4 °C / 85% RH, the dew point would be ≈ +1.7 °C; a condensing unit's coil would ice up and a silica gel rotor (AD series) unit would be required.

Complementary measures: • Gravity-flow racks and RFID/barcode pallet tracking with automatic FIFO allocation in the WMS • Continuous logging of temperature, RH and dew point with deviation alarms • A vestibule at the store entrance

Engineering Note

Eight critical criteria for FIFO + climate control integrated design:

• Ambient stability — warehouse temperature + dew point within ±1°C / ±0.5°Cdp; otherwise actual product shelf life deviates from label, invalidating FIFO assumptions • Temperature distribution — ±1°C max variation in the warehouse; hot spots cause mould, cold spots cause condensation • Dew-point management — warehouse ambient dew point must be below wall, fan blade, and drain surface temperatures; otherwise condensation + product damage • Air distribution pattern — multi-zone air distribution; no stagnant zones; 0.2–0.4 m/s between racks • Rack design — gravity-flow racks or FIFO-optimised standard racks; new pallet → back, old pallet → front • WMS integration — NKT - Climate Track data fed into WMS; dynamic shelf-life estimation, automatic FIFO allocation • Vestibules — vestibules at warehouse entries; prevent temperature-RH shock during transfers • Monitoring — temperature, RH, dew point, differential pressure, door openings, pallet movements continuously logged; annual report for HACCP

Quality indicators: hours outside target band <2%/year, FIFO violations <0.5%/year, actual product shelf life above 95% of labelled.

NKT Application Link

For this application NKT – Nem Kontrol Teknolojileri supplies the TFT CD 160-980 condensation dehumidifier, TFT AD series silica gel rotor dehumidifiers and TFT ADI/ADO freezer-room dehumidifiers. It supports unit selection with capacity calculation and technology matching based on space conditions, target temperature and RH (or dew point) and moisture load, and provides technical service and spare parts. Design, installation and commissioning remain within the scope of the facility's designer and contractor.