Fire-rated glass is a glass designed to minimize the spread of fire and smoke.
Fire glass is typically rated by two properties:
• Integrity - how long will the glass provide a barrier from the fire on one side of the pane?
• Insulation - how long will the glass prevent the excessive heating of the non-fire side of the glass?
For example, a glass rated as 60/30, will provide 60mins integrity and 30min insulation.
The glass must be officially and independently tested to gain certified ratings.
Fire-protective glass specifically rated for integrity only will minimise the spread of fire and smoke but will not limit radiant heat transfer through the door or window.
It is usually monolithic and is designed to not break under extremes of heat.
The rating of the resistance properties is generally rated in anything from 20 minutes to about 4-hours or more.
This is the expected duration of which the glass can effectively prevent the spread.
The glass prevents the transfer of heat, fire, and smoke due to an intumescent layer between the glass panels.
When the glass is heated, it is designed to shatter, which activates the intumescent inner-layer, causing it to expand and usually change colour.
It then works to block heat transfer. The amount of heat it can repel before failing depends on the chemistry of the entire piece of glass and frame.
Depending on the buildings' requirements, a wire can be added to the glass to make it a security fire-rated glass; helping to prevent it from being broken by force.