In chemical processing industries, sight glass provides a safe and reliable way to monitor reactions, fluid levels, and flow conditions inside vessels and pipelines. However, because these environments often involve corrosive substances such as acids, alkalis, and solvents, the corrosion resistance of the sight glass material becomes a decisive factor for both safety and longevity.

Borosilicate glass is one of the most common choices for chemical equipment. Thanks to its excellent chemical durability, it can resist attack from most acids, saline solutions, and organic solvents. Its performance only declines in environments with hydrofluoric acid or concentrated alkaline solutions, which can gradually erode the glass surface.

Quartz glass offers even higher resistance to chemical corrosion. Its extremely high purity and dense structure make it less reactive, even under exposure to strong acids or aggressive chemicals at elevated temperatures. This makes quartz glass ideal for specialized applications where both transparency and durability are required under harsh conditions.

Tempered glass, although mechanically strong and impact-resistant, is less suited for highly corrosive environments. Its protective advantage lies more in safety during breakage than in long-term chemical resistance. As such, it is typically chosen in applications where physical strength is prioritized over chemical durability.

To further enhance corrosion resistance, manufacturers may also apply special coatings or combine glass with protective linings. These measures extend the operational lifespan of sight glasses, reduce maintenance frequency, and ensure reliable observation in demanding environments.

In conclusion, the choice of sight glass in chemical equipment should be guided by the level of chemical exposure. Borosilicate offers broad resistance at a reasonable cost, quartz provides superior durability for extreme conditions, while tempered glass is better suited for safe, low-corrosion settings.