基于GB/T 18204.26—2000《公共场所空气中甲醛测定方法》,采用酚试剂分光光度法,根据国家标准要求,常温(8℃)下显色15min后比色。日常工作中发现,实验过程中环境温度较低的情况下,对显色有直接影响,低温下溶液显色不完全,导致样品含量有误差。针对此问题,对上述方法作了相应的改进。1材料与方法1.1试剂本方法采用的是实验室用纯水;所用的试剂无特殊要求下纯度一般为分析纯。 Based on GB / T 18204.26-2000 “Determination of Formaldehyde in Air of Public Places”, phenolic reagent spectrophotometry was used to colorimetrically colorize at room temperature (8 ℃) for 15 minutes according to the national standard. In daily work, it is found that under the condition of low ambient temperature during the experiment, it has a direct influence on the color development, and the solution color is incomplete at low temperature, resulting in an error in the sample content. In response to this problem, the above method has been improved accordingly. 1 Materials and methods 1.1 Reagents The method used in laboratory pure water; reagents used without special requirements of purity is generally analytical grade.