Formerly the owner and president of the Women’s Health Center of Putnam, PC, Dr. Steven Raheb serves as an adjunct biology professor at Quinebaug Valley Community College in Connecticut. In his free time, Steven Raheb volunteers as a celebrity food judge at community events. He also enjoys creating hand-thrown ceramics and glassblowing.

When blowing glass, one of the most important steps is annealing the glass, or allowing it to cool slowly. Annealing helps the glass maintain its strength and keeps it from cooling unevenly, which can cause the glass to crack or shatter. This type of glass is never used in vehicles because it forms jagged pieces when broken, posing a safety hazard.

If breaking while annealing occurs, it is often because the outside of the glass cools much faster than the inside. To prevent this, most annealing is completed in a special oven that allows the glass to come to a specific temperature and cool evenly over a long period, often around 14 hours. The general temperature range for most glass is around 850 to 900 degrees Fahrenheit; this is known as the stress-relief point of glass. Internal stress left in the glass is one way that it can shatter prematurely.