1. Preparation of test instruments:
(1) tray: Made of galvanized sheet materials.
(2) electronic platform scale: sensitivity 1 g, the biggest weighing:10000 g.
(3) Up-draught drying box

2. Method of measurement :
(1) Use a dry, clean try with a known weight to weigh coal sample 500 g (the accuracy is to 1 g), and  flat the coals samples evenly in the tray.
(2)Put the coal sample tray into a drying box that has been up-draught dried and heated  to 150 ~ 160 ℃, in 145 + 5 ℃ and continuously up-draft drying, the bituminous coal is dried for 30 min, and the anthracite coal is dried for 1 h, and the lignite is dried for 1.5 h. Then remove the tray from the drying box for weighing in hot condition. Then conduct checking test, each test lasts 15 min, until the reducing weight of coal samples is not more than 1 g or the coal sample weight is increased. In latter case, the weight of the coal before weight increasing shall be adopted as the calculation basis.
3. The results of calculation:
                    G1
        Mt＝                ×100
                     G
        where ：
       Mt - full moisture of coal sample, %.
G1 - weight reduced of coal sample after being dried, g.
G - the weight of the coal sample, g
The report value shall be rounded to one decimal place.

4. The permissible error: The difference tested in parallel shall not exceed the regulations in the table below: