THE RECEPTACLE FROM THE HEATING CHAMBER , QUICKLY REPLACE THE LID , LEAVE TO COOL FOR 30 TO 45 MINUTES IN A DRYER AND WEIGH ( WEIGHING MUST BE ACCURATE TO 1 MILLIGRAMME ) .
( B ) PRE-DRYING :
GRAINS WITH A MOISTURE CONTENT HIGHER THAN 17 % MUST BE PRE-DRIED AS FOLLOWS :
WEIGH 50 GRAMMES OF UNGROUND GRAIN IN A SUITABLE RECEPTACLE ( E.G . A 20 BY 12 CENTIMETRE ALUMINIUM PLATE WITH A 0.5 CENTIMETRE RIM ) , LEAVE TO DRY IN A HEATING CHAMBER FOR SEVEN TO TEN MINUTES AT A TEMPERATURE OF 130 * C , REMOVE FROM THE HEATING CHAMBER , LEAVE THE GRAINS UNCOVERED TO COOL IN THE LABORATORY FOR TWO HOURS AND WEIGH ( WEIGHING MUST BE ACCURATE TO 10 MILLIGRAMMES ) . CRUSH THE PARTIALLY DRIED GRAINS AND DETERMINE THE REMAINING MOISTURE CONTENT AS DESCRIBED IN ( A ) .
5 . METHOD OF CALCULATION AND FORMULAE : ( SEE O.J . NO L 281 OF 1 . 11 . 75 )
6 . ACCURACY OF TEST :
THE DIFFERENCE BETWEEN TWO TESTS MADE ON THE SAME SAMPLE MUST NOT EXCEED MORE OR LESS 0.1 % OF MOISTURE .
( 1 ) AIR TEMPERATURES INSIDE THE HEATING CHAMBER .
( 2 ) ITS HEATING CAPACITY SHOULD BE SUCH THAT , WHEN IT HAS BEEN PRE-SET TO 131 * C , THAT TEMPERATURE CAN BE REGAINED IN LESS THAN 45 MINUTES AFTER THE MAXIMUM NUMBER OF TEST SAMPLES HAVE BEEN PLACED IN THE CHAMBER TO DRY SIMULTANEOUSLY , VENTILATION SHOULD BE SUCH THAT , WHEN ALL TEST SAMPLES OF COMMON WHEAT IT CAN HOLD ARE DRIED FOR TWO HOURS , THE RESULTS DIFFER BY NO MORE THAT 0.15 % FROM THE RESULTS OBTAINED AFTER DRYING FOR FOUR HOURS .