Fire ratings for glass blocks are concerned with two criteria: fire integrity and thermal isolation.

To successfully pass testing, panels are tested to four standards (See Fire Resistance). A Brief definition of fire integrity is how long a wall will remain stable for in the case of a fire. Thermal isolation relates to the period of time it takes for the heat to transfer from the side of the fire through to the other face of the glass blocks.

Fire rating tests are measured in 15 minute increments & three types of fire blocks are available: 60 minute integrity & 15 minute thermal isolation, 60 / 30 & 60 / 60.

When a fire rated panel is built, it is not just the block that is tested, it is the complete panel. Ensuring the correct installation system & accessories used is crucial. All fire panels tested are constructed on the basis of rods & mortar. To comply, specific fitting guides should be specified & adhered to validate test certification.

Fire Resistance

Glass blocks under test conditions Fire resistance is concerned with four criteria :

1. Mechanical Resistance - the glass block wall must stay upright without too much damage following testing
2. Thermal isolation
3. Imperviousness against blaze
4. No flammable emission during testing.

These tests are recorded in 15 minute increments.

Definition :

FIRE INTEGRITY

 (G-CATEGORY GLAZING) The glass block wall must pass Test (1), (3) and (4) above.

THERMAL ISOLATION

(F-CATEGORY GLAZING) The glass block wall must pass all four of the criteria above.