What type of glass is most commonly used in transit bus windows?

Laminated safety glass is the correct choice for transit bus windows due to its unique construction, which enhances safety and performance. This type of glass consists of two or more layers of glass bonded together with a durable interlayer, typically made of polyvinyl butyral (PVB).

The primary advantage of laminated glass is its ability to remain intact even when shattered, which significantly reduces the risk of injury from flying shards in the event of an accident. This safety feature is crucial for protecting passengers and ensuring their well-being during travel. Additionally, laminated glass offers better sound insulation compared to other types of glass, contributing to a more comfortable experience for passengers by blocking out external noise.

While tempered glass is often used in areas requiring high resistance to impact and thermal changes, it does not possess the same safety retention properties when broken. Annealed glass, being a basic form of glass, is less durable and does not meet the rigorous safety standards required for transit vehicles. Polycarbonate glass, while lightweight and impact-resistant, is not commonly used in large applications like bus windows due to concerns over scratching and UV degradation.

Thus, laminated safety glass is the preferred option for transit bus windows because of its combination of safety benefits and passenger comfort features.