英语翻译-Use 4.5 kg/m3 coarse grade dust for each chamber as per

英语翻译-Use 4.5 kg/m3 coarse grade dust for each chamber as per SAE J 726.-Use a cubic chamber with dimensions appropriate for samples under test ,however not smaller than 915 mm side and with minimum 150 mm clearance between samples and walls and between samples,able to stir dust using compressed air or ventilators blowing from up downwards for uniform diffusion throughout chamber.-Non-ventilated test ambient ,23℃±5℃ temperature ,45 thru 70% relative Humidity.Test shall last 5 hours ,stirring dust 2 s at 15 min intervals