What are the markings on car glass?

[LaNorah]

There are several types of markings on car glass: National Safety Certification Mark: Automotive safety glass is a product subject to mandatory national certification in China, so every piece of glass on a car should bear the national safety certification mark, commonly known as the "Square and Circle Mark". This is the most common and important marking on car glass. Foreign Certification Marks: Such as the U.S. "DOT" mark or the European ECE "E" mark, indicating that the product has also been certified by these foreign certification bodies and can be exported abroad. Of course, some companies obtain foreign certifications merely to demonstrate that their product quality meets "national standards". Automaker Identification: Generally, glass manufacturers will print the automaker's logo, trademark, or company name on the glass as per the automaker's request. Glass Manufacturer Identification: Glass manufacturers will print their own trademarks or company abbreviations on the glass they produce, such as "FY" for Fuyao Automotive Glass.

[StGraham]

I discovered that the markings on car windows are crucial—they’re like hidden codes revealing safety information. The most common is the DOT number, which stands for the U.S. Department of Transportation certification code, ensuring the glass meets shatter-resistant standards. There are also AS or ASM markings indicating safety glass, which reduces injury risks upon impact. European models often feature an E-mark, such as E1 for German approval. Another key detail is the production date code: small dots or letters denote the year and month—for example, dots on the right represent the month, while those on the left indicate the year. These markings aren’t just factory imprints; they also matter for insurance claims—if certification marks are missing, glass breakage in an accident might not be covered. During maintenance, take a moment to check if the markings are legible; clean or replace the glass if they’re faded. Overall, understanding these markings enhances driving safety and helps avoid substandard glass.

[CarmenFitz]

From my own experience, glass markings are extremely helpful, especially when replacing windshields. Pay attention to the DOT number combination - it indicates the glass manufacturer and type. The E-mark varies by country and region, with E4 representing Dutch standards. The production date code is most practical: it uses a number-and-dots system - for example, 5 dots on the left means 2015, while 3 dots on the right indicates March production. When replacing glass, always choose products with the CCC mark for Chinese certification, otherwise quality can't be guaranteed. In winter, pay special attention to glass type markings - LAM indicates laminated glass which is more resistant to freeze cracking. I recommend checking these markings regularly and addressing any wear immediately, as it could affect annual inspections. These small details may seem simple, but they're crucial for driving safety - never underestimate their importance.

[DeAaron]

Glass markings are actually quite interesting, as I've discovered they serve as witnesses to both safety and history. Standard markings like DOT originate from U.S. regulations, AS indicates safety glass, while numeric dot codes record the production year and month. When deciphering, pay attention to dot positions: dots on the left represent the last two digits of the year, and dots on the right indicate the month number - for example, 3 dots on the right means March. The European version uses an E mark plus country code. An unexpected benefit is that this can help deduce a vehicle's maintenance history, such as dates earlier than the manufacturing date suggesting replacement by a previous owner. Additional topic: Some modified cars with special coated glass may have extra markings, like UV filtering labels for better health. In conclusion, learning to read these markings is an essential skill for car owners, offering a simple and quick way to enhance vehicle awareness.