INTRODUCTION
Respiratory system is the first tract that was harmed by
toxic dust.1 Prolong occupational exposure to the toxic
dust could irritate the respiratory system, damage the lung
tissues, create fibrotic tissues and impair lung function
(Occupational respiratory diseases) such as asthma,
asbestosis, silicosis etc.2-5 In Thailand, occupational
respiratory diseases have been increasing each year.6
Wood processing from furniture factory caused wood dust
and other health hazards including chemicals, bacteria and
mold. The dust are divided into 2 groups according to their
size, the first is called “Total dust” which particle are larger
than 10 micron (PM10), mainly are soft dust that could
enter the upper respiratory tract and excreted by coughing
or sneezing,7 another type is “Respirable dust” that has
particle smaller than 10 micron(PM