Can VOC detectors accurately measure formaldehyde? How are the two related?
1, Firstly, clarify the relationship between VOC and formaldehyde content
VOC refers to the general term for volatile organic compounds, which include various substances such as formaldehyde, benzene, toluene, xylene, and TVOC. Simply put, formaldehyde is one of the VOCs, but VOCs do not only contain formaldehyde. This is like the relationship between fruits and apples. Apples belong to the category of fruits, but tools used to measure the total amount of fruits may not accurately measure the individual content of apples.
Can the VOC detector accurately detect formaldehyde? Look at it in two situations
1. Ordinary universal VOC detector: difficult to accurately detect formaldehyde
Most conventional VOC detectors on the market, such as those using semiconductor sensors or PID photoionization sensors, are designed to detect the total amount of VOCs, rather than accurately quantifying single substances such as formaldehyde.
From the perspective of detection principle, this type of sensor will respond to various VOC components. During the detection process, it will simultaneously capture signals of various substances such as formaldehyde, benzene, toluene, etc. The final displayed value is the total VOC concentration of all these substances combined, and the specific content of formaldehyde cannot be distinguished separately.
From a precision perspective, even if some universal VOC detectors can react to formaldehyde, the interference of other VOC components may result in high or low formaldehyde detection results with significant errors, which cannot meet the requirements for accurate formaldehyde detection. For example, in indoor environments, determining whether formaldehyde meets the standard requires a relatively accurate numerical value, which is difficult for ordinary general-purpose VOC detectors to achieve.
2. VOC detector with formaldehyde special detection function: can achieve accurate detection
Some high-end VOC detectors adopt a dual sensor or composite detection module design, which not only detects the total amount of VOCs, but also comes equipped with specialized sensors for formaldehyde, such as electrochemical formaldehyde sensors. This type of equipment has the ability to simultaneously detect VOCs and formaldehyde.
In principle, sensors specifically designed to detect formaldehyde are only sensitive to formaldehyde molecules and can eliminate interference from other VOC components, outputting the concentration value of formaldehyde separately.
In practical applications, such devices are commonly used in indoor air detection scenarios, which can not only determine whether the total VOC exceeds the standard, but also accurately understand whether formaldehyde meets relevant standards. They are suitable for scenarios such as homes and offices that require clear detection of formaldehyde. However, when making a purchase, it is important to confirm whether the equipment is clearly labeled to support formaldehyde specific testing, in order to avoid treating ordinary general-purpose equipment as formaldehyde detectable.
