The purpose of this research is to study the effect of a safety system provided for external wall plastering activity on productivity by studying a construction of commercial buildings. The safety system composed of (1) stable scaffolding system (2) providing clean and not slip walkways on the scaffold (3) installation of handrails not less than 0.90 meters in height along sides of the scaffold (4) installing safety nets around outside perimeters of the scaffolding (5) indicating working area (6) installing stairs (7) providing protection for people who works below (8) providing tools and equipments for transporting material which are safe and ready for using and (9) providing personal protective equipment for workers. Cost of the safety system is 79665 baht for a wall area of 1510 m2 or approximately 53 baht/m2. The prevention cost is quite high because it is an initial investment cost. However contractors could repeat theirs used on future projects. Productivity rates for prior and after the used of safety system are 1.16 and 1.13 m2/person/hr respectively. The productivity declines for approximately 3%. In addition our study found an impact of predecessor activity which is a brick laying activity. If brick walls are not well aligned and plumbed the working time for wall plastering could take longer for 8%. Meanwhile the wall plastering productivity could decrease for 11% and labor cost could increase for 12%.

This research aimed to develop and study efficiency and effectiveness index of Vocational Course to ASEAN as well as to study level of satisfaction and work process skills of students who study V 33102 Vocational Course to ASEAN. The samples in this research were 65 Twelfth Grade students who enrolled in second semester of academic year 2012 at Soponsirirat School under the Secondary Education Service Area office 8 Ratchaburi province. The samples were selected by Purposive Sampling from two classes of Twelfth Grade students. Research tools consisted of curriculum lesson plans achievement test students’ satisfaction survey questionnaire and evaluation form of students’ work process skills. Data were statistically analyzed for Percentage Means and Standard Deviation. Results revealed that Curriculum and lesson plans of Vocational Course to ASEAN for Twelfth Grade students had higher efficiency than the standard of 80/80 (85.75/87.30). Effectiveness index was also higher than the standard of 0.50 (0.80). Students’ satisfaction in instruction was in the highest level and students’ working skills were also at very good level. This means that the course is suitable and could be adopted to prepare students for ASEAN Economic Community in every school under the Secondary Educational Service Area Office.