This document discusses specific application sprinklers for protecting hazards not covered by current standards. It provides background on the manager John Desrosier and defines what is meant by a "specific application." Special sprinklers are sprinklers tested and listed to protect specific hazards. The document describes how a specific application comes about and details tests done by UL investigating the effectiveness of standard spray sprinklers in sloped ceiling combustible construction. It outlines four sprinkler tests done by UL and shows layouts, setups and damage from the tests. Finally, it describes different types of attic sprinklers - back to back dual directional, single directional, HIP and attic plus sprinklers.

1. Specific Application Sprinklers
John Desrosier PE

2. John Desrosier PE
• Finished Undergraduate Degree 2009
• Interned at RJA (Walnut Creek, CA)
• Finished Masters 2010
• Worked for small special hazard contractor 2010
• Started in Tyco Technical Services 2011
• Transferred to Innovation and New Ventures 2013
• Transferred back to Technical services 2014
• Manager of Technical Services 2016- Present

3. What is meant by “Specific
Application”
• A method of developing specific design and protection
criteria for fire hazards not covered by current
Standards.
OR
• A method of developing “improved” specific design and
protection criteria for hazards currently covered by
Standards, but may be found to be insufficient by today’s
needs.

4. Special Sprinklers
3.6.4.9 Special Sprinkler
A sprinkler that has been tested and listed as prescribed in 8.4.8
8.4.8 Special Sprinklers.
8.4.8.1* Special sprinklers that are intended for the protection of specific hazards or
construction features shall be permitted where such devices have been evaluated and
listed for performance under the following conditions:
(1) Fire tests related to the intended hazard
(2) Distribution of the spray pattern with respect to wetting of floors and walls
(3) Distribution of the spray pattern with respect to obstructions
(4) Evaluation of the thermal sensitivity of the sprinkler
(5) Performance under horizontal or sloped ceilings
(6) Area of design
(7) Allowable clearance to ceilings

5. How does a “Specific Application”
come about?
• A need is identified by:
– Manufacturer
– Consortium (e.g. Retail Groups; Building
Manufacturers; Tire Manufacturers; etc)
– Insurance Underwriters
– Private Sector

6. • Questions were raised as to
the level of protection
provided by quick response
standard spray sprinklers in
sloped ceiling combustible
construction.
• UL ran a series of six full
scale fire tests investigating
this effectiveness.
Sprinkler Protection of Sloped Combustible
Concealed Spaces

7. Test No. 2 (7 psi)
Test No.
Number of
Sprinklers
Operated
Test Duration
min:sec
Sprinkler
Operation, I.D.
No. – Time
min:sec
Approximate
Consumed
Area of Roof
Deck
Fire Involvement
Area
1 – 1:33
2 – 1:38
Damage Assessment
(Approximate Areas)
2 2 20:00 47 sq. ft. 60 sq. ft.

8. UL Std. Sprinkler Test #2

9. Test No. 3 (20 psi)
Test No.
Number of
Sprinklers
Operated
Test Duration
min:sec
Sprinkler
Operation, I.D.
No. – Time
min:sec
Approximate
Consumed
Area of Roof
Deck
Fire Involvement
Area
1 – 0:34
2 – 0:36
Damage Assessment
(Approximate Areas)
6 sq. ft.3 2 20:00 2 sq. ft.

10. UL Std. Sprinkler Test #3

11. • 4 sprinklers were installed 10” below the roof deck.
– 2 at the peak spaced 10 ft. apart & 2 sprinklers at 10’
apart installed 12’ down the slope.
• A plastic ridge vent was installed at the peak with a 2”
gap between the plywood deck edges.
• The ignition source placed near the eave 30” from the
bottom edge of the truss between 2 sprinklers.
• Sprinklers water discharge pressure: 20 psi.
UL Std. Sprinkler Test #4

12. UL Std. Sprinkler Test #4 - Layout
Peak
5’-0”5’-0”

13. UL Std. Sprinkler Test #4 - Set-up

14. Test No. 4
9:13 s. after Ignition 14:08 s. after Ignition

15. Plan View of Roof Damage

16. Types of Attic Sprinklers

17. Types of Attic Sprinklers
Back to Back Dual Directional
• Light Hazard Construction
• 4.2K, 5.6K, and 8.0K
• Roof Pitches of 3:12 up to 12:12
• Maximum Distance Between Sprinklers = 6 feet
• Minimum Distance Between Sprinklers = 4

18. Back to Back (BB) Spray

19. Types of Attic Sprinklers
Single Directional
• Light Hazard Construction
• 5.6K
• Roof Pitches of 4:12 up to 12:12
• Maximum Distance Between Sprinklers = 6 feet
• Minimum Distance Between Sprinklers = 4

20. Types of Attic Sprinklers
HIP Sprinkler
• Light Hazard Construction
• 5.6K
• Roof Pitches of 4:12 up to 12:12
• Maximum Distance Between Sprinklers = 6 feet
• Minimum Distance Between Sprinklers = 3

21. Hip Spray

22. Types of Attic Sprinklers
Attic Plus Sprinkler
• Light Hazard Construction
• 4.2K, 5.6K
• Roof Pitches of 3:12 up to 12:12
• Maximum Distance Between Sprinklers = 10 feet perpendicular to
the slope and 12 feet parallel to the slope (No 20 psi penalty >8’)
• Minimum Distance Between Sprinklers = 7

23. AP Spray (& SSU)