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Have you ever felt dizzy when entering a newly renovated room? Or do you always detect a faint "chemical smell" at home? This is likely the work of VOCs. The so-called VOCs, short for Volatile Organic Compounds, may sound professional, but they are actually closely related to daily life and even quietly affect our health every day.

1. What Are VOCs?

VOCs are the abbreviation of Volatile Organic Compounds, and different institutions have slightly different definitions for them:

??The American ASTM standard emphasizes: organic compounds that can participate in atmospheric photochemical reactions;
??The World Health Organization (WHO) classifies them by boiling point: volatile organic substances with a boiling point between 50°C and 260°C;
?? The German standard is more concise: organic substances that can volatilize automatically under normal temperature and pressure.

In layman's terms, VOCs in the general sense refer to organic compounds that easily volatilize into the air, while in the environmental protection field, more attention is paid to the categories that can undergo photochemical reactions and are harmful to the environment and human body.

TVOC stands for "Total Volatile Organic Compounds". There may be hundreds of types of VOCs existing simultaneously indoors. Although the concentration of a single type is relatively low, the combined toxic effects of multiple VOCs cannot be ignored.

The most convenient and common method to define which substances belong to VOCs is based on their boiling points. The most widely accepted consensus is that VOCs refer to chemical substances with a boiling point equal to or lower than 250°C. Therefore, those with a boiling point exceeding 250°C, which are not classified as VOCs, are often called plasticizers.

2.Main Hazards of VOCs

At present, more than 900 types of indoor chemical and biological substances have been identified, among which there are at least 350 types of VOCs, including more than 20 carcinogens or mutagens.

Common Health Impacts Include:

- Irritation to the eyes, nose, and throat, causing dry eyes, stinging, increased blinking frequency, and tearing;
- Dryness and pain in the nasopharynx, nosebleeds, nasal congestion, accompanied by coughing, hoarseness, and changes in the sense of smell;
-  Congestion and inflammation of the throat;
- Dry skin, itching, stinging, and the appearance of erythema.
In Severe Cases, It May Lead To:

- Abnormal neurological functions and even dementia;
- Induction of hypersensitivity pneumonitis.

3.What Are the Sources of VOCs?

VOC pollution comes from a wide range of sources. Most organic chemical products, synthetic materials, fuels, tobacco combustion, etc., will release VOCs:

Renovation，

- Various coatings and adhesives;

- Artificial boards;

- Wooden furniture and wood lacquers;

- Plastic products;

- Synthetic fabrics such as carpets;

- Leather and sponge products;

Others，

-  Ink used in printing;
-  Other household chemicals;
-  Combustion of fuels and tobacco.

4.How to Detect VOCs?

Commonly used VOC detection methods in China mainly include:

? Gas Chromatography-Flame Ionization Detection (GC-FID);
? Fourier Transform Infrared Spectroscopy (FTIR);
? Photoionization Detection (PID).