There have been a lot of large scale occurrences of fire when new buildings are being made, despite a fact that many people think there is no reason of fire occurrence at a new project. This is to study how to measure the occurrence risk of fire at a construction site especially when they work gas welding and cutting around plastic material piles. Statistic analysis such as frequency analysis, cross analysis, correlation analysis are made to produce those elements which the goals of the study can be shown. Questionnaire survey sheets are made after considering factors shown in the previous introduction. workers' experience, work kinds, ages are the most important factors which they are considered for the study. Emergency lights, emergency brocast facility fire extinguishers are the highly rated by the workers for the questionnaire survey this time.