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Tuesday, September 23, 2014

Glossary of terms

Glossary of terms

Absolute Humidity
Actual weight of water vapour in a parcel of air and is expressed in
grams per cubic metre. The greater the air temperature the more water vapour that it can absorb before becoming saturated 

Anti - Chamber
This  is  a  chamber  or  facility,  which  ensures  that  cool-room conditions  exist  in  the  transfer  area  when  cargo  is  loaded  from storage into the container.

Air-bagging
Bags filled with air are used in containers that are not full of cargo to fill large gaps to prevent cargo movement without restricting airflow. 

Broken Stowage
Unfilled spaces throughout the container.

Controlled Atmosphere
The gas mixture surrounding the cargo is controlled so that its composition is as desired

Dew Point Temperature
Temperature at which the air has to be cooled for the water vapour to condense out into water droplets. It is also known as the saturation temperature, and is dependent on the absolute humidity

Chock
Block or wedge used to prevent movement of cargo within the container

Dunnage
Timber utilised to provide space within the stow of cargo to permit ventilation.

Hydro-cooling
A process in which the produce is rapidly cooled after harvesting by spraying, drenching or immersion with cold water

Kazoo
The nozzle on the container drain plug.

Modified Atmosphere
Gases are removed or added to create an atmospheric composition,
which is different from that of air around the commodity


Partlow Chart
This is a clock-based analogue temperature recording circular chart. 
It traces and records the delivery or return air temperature within the 
container

Relative Humidity
Ratio between the amount of water vapour in the air and the amount it  can  contain  at  that  temperature.  It  is  usually  expressed  as  a percentage

Senescence
Ageing of the commodity

Set Point
Temperature setting on the controller of the refrigeration unit

Shrink Wrapping
Application of a protective synthetic plastic wrapping material to unitise slip sheeted and/or palletised loads, improving handling and protecting the goods from shifting during transit

Slip Sheets
A thin corrugated fibreboard or plastic sheets used in place of a pallet to maximise space utilisation. Slip sheeting requires special forklift attachments.

Stowage Factor
Volume occupied by unit weight of cargo. Usually expressed as cubic metres per tonne. It does not take into account any space, which may be lost due to broken stowage

Sweat or Condensation
Is formed when the water vapour in the air condenses out into water droplets  when the air is  cooled  below the dewpoint. The water droplets may be deposited onto the container structure or onto the cargo and packages.

Vacuum-cooling
This is  a post harvest/pre-shipment process, which relies on the cooling effect  of  water  evaporation on or within the product to reduce temperature.  It  requires  a  vacuum chamber to lower the boiling point of the moisture in the product

Ventilate
To allow fresh air to circulate throughout the cargo in the container