To facilitate the quantitive indication on dust, to recognize the dust generating state and to proceed the examination on a welding condition and working environment based on dust generating quantity quantitively indicated without accepting subjectivety of measuring people by only photographing welding work itself with an infrared camera during actual welding work at site.
The weld zone periphery is photographed with the infrared camera 12, and obtained infrared information is converted into temperature information with a temperature arithmetic part 18. Further, whether temperature information is information that dust becomes a heat source or not is discriminated with the dust discriminating constant executing dust discrimination based on the distribution density of temperature information using a dust arithmetic part 22, the total sum of information discriminated as temperature information due to dust is obtained, the dust generating index corresponding to dust generating quantity is calculated, whereby the dust generating state is recognized.
SAKAMOTO YOSHITAKA
NISHIO MASAHIRO
