Abstract Temperature difference between metallic surfaces and surrounding bulk air caused by sun heating and nocturnal radiation cooling challenges the accuracy of the time of wetness (TOW) determined from meteorological data. In this paper, the importance of measuring surface relative humidity (SRH) in preference to air relative humidity (RH) for determination of TOW and corrosivity is demonstrated. The TOW established from SRH data was from 33 to 40 % higher than that based on air RH data obtained during outdoor monitoring for a year, depending on the surface colour. Measurements with a galvanic sensor ascertained the correctness of the new procedure.

中文翻译：

---

通过表面相对湿度实现更真实的湿度测量

摘要 由太阳加热和夜间辐射冷却引起的金属表面与周围大量空气之间的温差对根据气象数据确定的湿润时间 (TOW) 的准确性提出了挑战。在本文中，证明了测量表面相对湿度 (SRH) 而非空气相对湿度 (RH) 对测定 TOW 和腐蚀性的重要性。根据表面颜色，根据 SRH 数据确定的 TOW 比基于一年室外监测期间获得的空气 RH 数据的 TOW 高 33% 至 40%。使用电流传感器进行的测量确定了新程序的正确性。