อิทธิพลของความชื้นและแสงแดดต่อการเสื่อมสภาพของจิตรกรรมฝาผนังในวัด / กตัญชลี เวชวิมล = Effects of moisture and sunlight on mural paintings in temples / Katunchalee Wechwimol
Moisture and sunlight are known to be the main factors causing deterioration to the mural paintings in Thailand. To study these factors, Wat Paorohit, which already inserted stainless steel sheets into the wall to prevent rising damp, had been selected to compare with Wat Suwannaram Ratchaworaviharn, which did not do so. These two temples were selected since their locations were closed to the water catchments and these two temples were decorated with the same age mural paintings. The study involved moisture on surface wall, relative humidity, light intensity and UV radiation on suface wall. The study on deterioration of the mural painting was the estimation in percentage of deterioration space together with analyzing the component of various salt remained on surface wall. The study revealed that waterproof membrane can prevent rising damp but the problem still exists from the remaining salt on the wall. The moisture on surface wall in Wat Paorohit was lower than in Wat Suwannaram. The relative humidity in the interior of both of temples was not different. The interior relative humidity in Wat Suwannaram was higher than the exterior relative humidity, but the interior humidity in Wat Paorohit was not different from the exterior relative humidity. Moisture on surface wall of both temples related to interior relative humidity. Moisture on surface wall depended on the height levels from ground, seasons and position of the wall. No difference on time of the day for moisture on surface wall. Furthermore, light intensity and UV radiation in Wat Paorohit were higher than Wat Suwannaram. Light intensity and UV radiation depended on seasons, time of the day and position of wall. Moisture on surface wall in Wat Paorohit related to light intensity and UV radiation but in a rather low level. While moisture on surface wall in Wat Suwannaram did not relate to light intensity nor UV radiation. Percentage in deterioration of mural paintings in Wat Suwannaram showed relation to moisture on surface wall but did not show relation to light intensity and UV radiation on the wall. While in Wat Paorohit, percentage in deterioration could not be concluded on the relationships to all of three factors because the lower part of mural paining in this temple used to be cover with mortar. Varieties of salt found on the walls of both temples are composite of building materials, which is not salt from rising damp.
