Moisture in the stored commodities is one of the important factors causing qualitative and quantitative deterioration during storage . Food grains which are dried plants material tend to absorb moisture from all sources including atmospheric air , godown floor , godown walls etc . other stored commodities such as jute , cotton etc. also absorb moisture from the floor . Higher the moisture content in the stored commodities , faster is the deterioration due to insect and microbial activities and , therefore lesser is the storability .
The stored commodities also loose weight due to driage resulting in quantity loss . Permissible limits of such driage loss in different commodities depending upon the period of storage are provided in the respective Local Warehouse Rules . Moisture content of the stocks at the time of receipt and delivery is , therefore recorded using appropriate type of moisture meter and duly authenticated by depositor .
In order to prevent absorption of floor moisture by bottom layer bags/packages , the commodities are staked on appropriate dunnage ,
Following dunnage materials are commonly used at the warehouse :-
a) Wooden crates or HDPE crates of size 5'*2' or other appropriate size .
b) Bamboo mats prepared out of closely woven bamboo strips
c) Polythene films of atleast 100 micron thickness .
While wooden crate is the most ideal dunnage . However , in the view of scarcity of good quality wood due to restriction in deforestation and consequent high cost , stocks at the warehouse are also stacked by providing two layers of bamboo mats with sandwiched layer of polythene film .