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Definitions and links

Definitions used in commercial (retail) and professional (catering) cabinet/case testing

Air curtain – jet of air, used to reduce infiltration (seal) of cold air (within cabinet) with warmer ambient air (outside of the cabinet) instead of a door. In a vertical multi-deck, the jet travels from top to bottom. In a horizontal cabinet the jet travels horizontally across the top of the cabinet.

Air discharge - opening for the discharge of the air curtain.

Air return - opening for the air toto return to the cold heat exchanger.

Assisted service refrigerated display cabinet/case - serve-over refrigerated display counter cabinet where a person serves the consumer.

Automatic defrosting - defrosting where no action by the user is necessary to initiate the removal of frost accumulation and to restore normal operation.

Base deck – base of well in which goods are displayed, lowest display surface of a cabinet.

BS EN 441 – test standard used to assess temperature and energy performance of professional cabinets for ECA accreditation.

BS EN ISO 23953 – test standard used to assess and energy performance of commercial retail display cabinets.

Cabinet classification - standard classification method used in EN23953 to define temperature performance of a cabinet (e.g. M1, M2, H1, H2, L1, L2).

Canopy - upper panel or overhang on a vertical cabinet.

Centralised direct expansion supermarket system - central plant in the form of a series of compressors and condensers located in a machinery room or an outside location that feeds refrigerant to display cabinets.

Centralized indirect supermarket system (secondary loop) - refrigeration for display cabinets provided by a secondary fluid which is pumped between the central plant and the refrigerated display cases.

Chest cabinet – horizontal closed cabinet with transparent lid for retail display, may be opaque for catering or domestic storage.

Chilled or medium temperature (MT) cabinet – cabinet to maintain food at chilled temperature (usually classified according to EN23953:2005 as M1, M2, H1, H2).

Climate class – test room climate (ambient) classification according to the dry bulb temperature and relative humidity.

Closed refrigerated display cabinet - refrigerated cabinet where access to the food is gained by opening a door or lid.

Combined (vertical/horizontal/multi-deck) - cabinet consisting of both vertical and horizontal refrigerated compartments.

Commercial refrigeration appliance - an insulated cabinet, with one or more compartments, intended for display of refrigerated or frozen foodstuffs, but accessible to the end user.

Compression-type refrigerating system - system in which refrigeration is achieved by the vaporisation at low pressure in a heat exchanger (evaporator) of a liquid refrigerant. The vapour is then mechanically compressed to a higher pressure and subsequently cooled and condensed in another heat exchanger (condenser.

Condensing unit - combination of one or more compressors, condensers, liquid receivers (where applicable) and accessories.

Defrosting - removal of frost, snow and ice from surfaces (mainly the evaporator) in a refrigerated display cabinet.

Direct electrical energy consumption (DEC) - energy consumption of electrical components in the cabinet (e.g. lights, fans etc).

Discharge air grille (DAG) – honeycomb or slot for air discharge to straighten the flow and damp turbulence. 

Duty (capacity) – heat extracted by the cabinet (in kW).

Ecodesign - the integration of environmental aspects into product design with the aim of improving the environmental performance of the product throughout its whole life cycle.

Ecodesign requirement - any requirement in relation to a product, or the design of a product, intended to improve its environmental performance, or any requirement for the supply of information with regard to the environmental aspects of a product.

Electric defrost – use of electric resistive heaters to defrost the cabinet.

End wall - panel fixed to side of cabinet.

Energy Technology List (ETL) – list of ECA products.

Energy-related product - any item that has an impact on energy consumption during use which is placed on the market and/or put into service, and includes parts intended to be incorporated into energy-related products covered by EC Directive 2009/125/EC which are placed on the market and/or put into service as individual parts for end-users and of which the environmental performance can be assessed independently.

Enhanced Capital Allowance (ECA) scheme – UK based scheme that identifies most energy efficient cabinets.

Environmental impact - any change to the environment wholly or partially resulting from a product during its life cycle.

Foodstuffs - food, ingredients, beverages, including wine, and other items primarily intended for consumption which require refrigeration at specified temperatures.

Forced air circulation -  where the air circulation within a cabinet is produce by means of external force (i.e. fans)

Front riser – vertical (usually transparent) device for retaining the goods within the display area.

Frozen or low temperature (LT) cabinet/case – cabinet to maintain food at frozen temperature (usually classified according to EN23953:2005 as L1, L2)

Full glass door cabinet (FGD) – cabinet with vertical transparent doors over the full height of a cabinet.

H1 - all ‘m’ packs equal to or greater than 1°C and equal to or less than 10°C.

H2 - all ‘m’ packs equal to or greater than -1°C and equal to or less than 10°C.

Heat extraction rate – energy removed by evaporator per unit time (in kW).

Horizontal cabinet (counter) – cabinet with horizontal display opening at the top, products accessible from above through open top, may sometimes have a lid. Cabinets usually have horizontal or near horizontal air curtain.

Hot gas defrosting – use of hot gas from the compressor discharge to defrost the cabinet.

Household refrigerating appliance - an insulated cabinet, with one or more compartments, intended for refrigerating or freezing foodstuffs, or for the storage of refrigerated or frozen foodstuffs for non-professional purposes.

Indirect-type refrigerating system – system where a secondary refrigerant circulating system is used to transfer heat between a central refrigerating system and a refrigerated cabinet.

Integral / self contained / plug-in refrigeration system - a refrigerated cabinet that has the condensing unit built into the cabinet

Island site cabinet – cabinet that can be accessed from all sides and can be multiplexed to form a larger island.

Kick plate - vertical plate or plinth at front of cabinet that covers the gap between the floor and base of the cabinet.

L1 - the warmest ‘m’ pack should have a maximum temperature equal to or lower than –15°C and a minimum temperature equal to or lower than –18°C.

L2 - the warmest ‘m’ pack should have a maximum temperature equal to or lower than –12°C and a minimum temperature equal to or lower than –18°C.

Life cycle - the consecutive and interlinked stages of a product life from raw material use to final disposal.

Load limit –maximum loading area where test packs can be maintained within a defined temperature class. May be marked as load limit line by the manufacturer.

M pack – 500 g test package fitted with a temperature measuring sensor.

M package temperature class - classification of M-package temperature according to their temperature.

M0 - all ‘m’ packs equal to or greater than -1°C and equal to or less than 4°C.

M1 - all ‘m’ packs equal to or greater than -1°C and equal to or less than 5°C.

M2 - all ‘m’ packs equal to or greater than -1°C and equal to or less than 7°C.

Manual defrosting - defrosting where an action by the user is necessary to initiate the removal of frost formation and return to normal operation requires action by the user.

MEPS – Minimum Energy Performance Standards. Maximum energy allowed to be used for products to be sold.

Multi-deck cabinet/case – vertical cabinet without doors and with multiple shelves..

Multi-temperature cabinet – cabinet capable of maintaining food in 2 or more compartments operating at different temperatures.

Night blind - type of night cover. Cover used to cover open area of display cabinet. May be manually or automatically operated.

Night cover - lid, blind or cover used to cover open area of cabinet during periods when cabinet is not being used by customers.

Off-cycle defrost – passive defrost, where ice melts naturally during a defined defrost period when the refrigeration system does not operate.

Pass-through – cabinet with hinged or sliding doors on both the front and rear of the refrigerator or freezer.

Professional refrigerating appliance - an insulated cabinet, with one or more compartments, intended for storage of refrigerated or frozen foodstuffs in commercial kitchens.

Refrigerated display cabinet/case - cabinet cooled by a refrigerating system which enables chilled and frozen foodstuffs placed within the display area to be maintained within prescribed temperature limits.

Refrigeration electrical energy (REC) - energy consumption of a conventional refrigeration system necessary to operate the cabinet.

Remote condensing unit – system to refrigerate a remote cabinet.

Remote refrigeration cabinet/case - a cabinet where the refrigerating components are remotely located from the cabinet, usually in a central plant room.

Return air grille (RAG) – air grille at bottom or front of cabinet for air return to evaporator.

Roll-in – cabinet that allows racks on wheels to be wheeled into refrigerated storage area.

Secondary refrigerant - liquid or liquid-solid or gas-liquid fluid used in an indirect type refrigerating system to transfer heat between a primary refrigeration system (usually direct expansion) and the refrigerated cabinet.

Self-service refrigerated display cabinet – cabinet where customer selects food (usually prepacked).

Semi vertical cabinet – cabinet with angled profile or inclined display opening with overall height of less than 1.5 m.

Semi-automatic defrosting - defrosting where an action by the user is necessary to initiate the removal of frost formation but normal operation is restored automatically.

Serve-over (deli / service over counter) – flat or slightly sloping based cabinet, usually intended for service of delicatessen or raw unpackaged foods, usually with rear opening (sometimes with hinged or sliding doors) and glass front display.

Serve-over counter with integrated storage - refrigerated display cabinet for assisted service which includes refrigerated storage (usually in base).

Shelf - surface on which the goods are displayed (excludes base deck).

Shelf sham - device to limit the loading of a display surface.

Static air cabinet – cabinet with natural, not forced-air circulation.

Superheat (evaporator) – temperature difference between refrigerant vapour at suction of evaporator and its saturation temperature.

Temperature classification – standard classification method used in BS EN ISO 23953 and BS EN 441 to define temperature performance of a cabinet (e.g. M1, M2, H1, H2, L1, L2).

Test package – packs used to load cabinet when testing to EN441 or EN23953.

Test room/chamber – a test facility to allow testing to a particular standard, e.g. BS EN441 for professional cabinets and BS EN ISO 23953 for commercial cabinets.

Total display area (TDA) - total visible area where food is displayed (includes visible area through the glazing), defined by the sum of horizontal and vertical projected surface areas of the net volume multiplied by the transmission factor through any transparent material.

Total energy consumption (TEC) - sum of DEC and REC.

Under-counter - refrigerated cabinet without a worktop surface, which is intended for installation under a separate counter.

Vertical/multi-deck cabinet/case – cabinet with open front, either with vertical air curtain or slightly angled air curtain. May be semi-vertical, multi-deck, roll-in or glass door type of cabinet.

Wall site cabinet – cabinet located with its back to a wall or back to back with another cabinet.

Warm gas defrosting – use of warm gas from the receiver to defrost the cabinet.


Useful links



Food Composition

Food History

Food Process Engineering

Freezing and Supercooling


Heat & Mass Transfer Modelling



Predictive Microbiology Modelling

Risk Assessment and HACCP

UK Organisations / Associations

International Organisations / Associations / Institutes





Institute of Food Technologists (IFT)

BBC - GCSE Bitsize - Design & Technology / Food Technology


Carbon Trust - Carbon Trust

Resource Efficiency KTN - Resource Efficiency Knowledge Transfer Network

FCRN - Food Climate Research Network

SIRAC - Sustainable Innovations in Refrigeration and Air Conditioning

The Food Chain Sustainability SIG - The Food Chain Sustainability Special Interest Group

WRAP -Waste Resources Action Programme

Food Composition

USDA ARS National Nutrient Database for Standard Reference

Food History

The Food Timeline: Food History Reference & Research Service

Food Process Engineering

Food Engineering - Website of R. Paul Singh, Professor of Food Engineering, Department of Food Science and Technology, University of California, USA

Unit Operations in Food processing - on-line access to famous food process engineering book by R. L. Earle, New Zealand

Freezing and Supercooling

Theoretical Aspects of the Freezing Process - University of Guelph, Canada

Cryobiology - A short course - University of Calgary, Canada

Freezing theory - Mississippi State University, USA

Examples of supercooling can be found on YouTube

Salt and the freezing point of water - Science Experiments


OneFish Community Knowledge Directory - Fish Technology Knowledge Base

Archive of the former Torry Research Station, UK

Heat & Mass Transfer Modelling

Useful Excel spreadsheet for the calculation of food cooling, freezing and thawing times using simplified methods - Q. Tuan Pham


Information for the UK meat industry


Sydney Postharvest Laboratory - Research and Advice for the Australian and International Fresh Fruit & Vegetable Industry

The Commercial Storage of Fruits, Vegetables, and Florist and Nursery Stocks - USDA, ARS Agriculture Handbook Number 66

Predictive Microbiology Modelling

ComBase - A combined database for Predictive Microbiology

Growth Predictor - Institute of Food Research, UK

Lists of available predictive microbiology application software

MicroFit - Institute of Food Research, UK

Modelling and simulation files - mixed models for Cl. perfringens growth in cooked meat, pathogens in sprouts, handwashing etc - Donald W. Schaffner, Department of Food Science, Rutgers, The State University of New Jersey, USA

Pathogen Modelling Program & other excel models - Microbial Food Safety research Unit Product and Services, USDA ARS

Risk Ranger - Australian Food Safety Centre

Seafood Spoilage and Safety Predictor (SSSP) - Danish Institute for Fisheries Research

Risk Assessment and HACCP

MED-VET-NET - European network of excellence working for the prevention and control of zoonoses and food borne diseases

UK Organisations / Associations

BFFF - British Frozen Food Federation

BPEX - British Pig Executive

BRC - British Retail Consortium

BRE - Building Research Establishment

BRI - Brewing Research International

BSI - British Standards Institute

CRT - Cambridge Refrigeration Technology

CCFRA - Campden and Chorleywood Food Research Association

CFA - Chilled Food Association

Defra - Department for Food and Rural Affairs

FPFP - Food Processing Faraday Partnership

FSA - Food Standards Agency

HPA - Health Protection Agency

LFR - Leatherhead Food Research

IChemE - Institute of Chemical Engineers

IFR - Institute of Food Research

IFST - Institute of Food Science & Technology

IMechE - Institute of Mechanical Engineers

IoR - Institute of Refrigeration

MLC - Meat & Livestock Commission

SALSA - Safe and Local Supplier Approval

SFAM - Society for Applied Microbiology

SOFHT - Society of Food Hygiene Technology

VLA - Veterinary Laboratories Agency

International Organisations / Associations / Institutes

AgResearch MIRINZ

Air-Conditioning & Refrigeration Institute (USA)

Alternative Fluorocarbons Environmental Acceptability Study (AFEAS)

American National Standards Institute

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)

European Food Safety Authority (EFSA)

FAO/WHO Codex Alimentarius

Food Science Australia: Meat Industry Services

International Institute of Refrigeration (IIR)

Institute of Food Technologists (IFT)

International Standards Organisation (ISO)

International Union of Food Science & Technology (IUFoST)

Natick Soldier Center

The American Meat Science Association (AMSA)

UN FAO Nutrition & consumer protection

UN Food & Agriculture Organization (FAO)

UN Industrial Development Organization (UNIDO)

UN World Health Organisation (WHO)

United Nations Economic Commission for Europe (UNECE)

USDA ARS News and Information

WHO food


UK Food Regulations - University of Reading


The Really Easy Statistics Site Jim Deacon, Biology Teaching Organisation, University of Edinburgh