1080-1081 / 1143
Most Frequently Asked Question:
“What Standard does this Come From?”
International Standard? Certainly
Not…
Grade
Fire Size (RHO) Alarm
Fire Size (RHO)
Control Action
High
10kW
10kW
Medium
10kW
50kW
Low
100kW
250kW
Special
Special - to be defined if
none of the above is
suitable.
Special - to be
defined if none of
the above is
suitable.
Grade
Effective Viewing
Distance
(Alarm)
Effective Viewing
Distance
(Control Action)
Medium -
High
0.5D
1.0D
Low
1.5D
3.0D
Special
Special - to be defined
if none of the above is
suitable.
Special - to be
defined if none of
the above is
suitable.
Methodology
• Magic numbers/rules of thumb - original intent
• Demonstrate compliance
• “That’s how we’ve always done it”
• Too onerous, “streamline expenditure” (Current update)