Storage Protection Using Horizontal Barriers and Large K-Factor, Extended Coverage In-Rack Sprinklers

Michael Billstroem Director of International Technical Services The Reliable Automatic Sprinkler Co., Inc.

As an Industry, we have spent the last 30 years trying to eliminate in-rack sprinklers. Are they coming back?

Current Trends & Developments:

Higher buildings using Automated Storage and Retrieval Systems (ASRS). . More exposed plastic storage

Lower water demands by using horizontal in-rack barriers. Using N252 EC as in-rack sprinklers

 NFPA Fire Protection Research Foundation work forms the basis of our new approach.  Initial Project to improve on methods of storing EEP and allowing for retrofit.

 Testing carried out at Underwriters Laboratories (UL)  Standard fuel package for EEP tests using polystyrene meat trays.

Test Parameters.  Commodity: Exposed, Expanded Class A Plastics  Ceiling Height:12.2m  Storage Height: 10.7m  Horizontal Barrier: 10mm Plywood at 6.1m (as per FM 8-9 and NFPA 13)  Ceiling Sprinklers: K=16.8 ESFR Sprinklers 100°C @ 3.4bar  In-rack sprinklers: N252EC K=360 Extended Coverage Pendent Sprinklers 100°C @ 2.07bar

Reliable Model N252-EC Extended Coverage Pendent Sprinkler  K=360  UL Listed, FM approved as a ceiling application sprinkler  100°C version was used for all testing

The Model N252 EC Pendent Sprinkler is a component of the N-Rack-EC™ Fire Protection System – Patent Pending

100mm clearance above commodity 50mm deflector distance below beam

1200mm aisle width

Spray Pattern @ 2.07bar

Target Array

Installation Method. N252-EC Sprinklers  Centred in Longitudinal Flue and Centred Between Rack Uprights = 2,515mm on centre.

 The horizontal barrier was left open at the rack uprights and no sprinklers are installed in the transverse flue or at the face of the racks.

Exposed Expanded Class A Plastics Fire Test.

Results.  Opened one (1) sprinkler at the ceiling @ 1 minute/2 seconds 3.4bar and 450 lpm  Opened two (2) sprinklers in the rack @ 49 seconds and 52 seconds  2.07bar and 522 lpm each or 1044 lpm total

After N-252 EC with Horizontal Barrier

Proposed Design Ceiling K-16.8 ESFR

Temp(C)

Bar

LPM/spr

No. of sprs . calculated

System Demand in LPM

100°

3.4

450

12

5,405+

100°

2.07

522

3

1,567+

In-Rack N-252 EC Pendent

For comparison: Actual water demands will be higher based upon hydraulic calculations.

The in-rack sprinkler demand would not be added to the ceiling demand because of the horizontal barrier. The total system demand would be the ceiling demand at 5,405+ LPM

Existing Ceiling Sprinkler Design (FM) for Exposed Expanded Plastics stored in Open Racks with 12.2m Ceiling and 10.7m storage.

Proposed K-16.8 ESFR & N252 In Rack

Bar

LPM/spr

No. of sprs . calculated

Hose Stream in LPM

System Demand in LPM

3.4

450

12

946

5,405+

5.17

829

20

1,893

18,473+

FM DS 8-9 K-25 ESFR Pendent

For comparison: Actual water demands will be higher based upon hydraulic calculations. Also note current 8-9 system has 2 hour water demand. On this basis total water saving would be +/- 1,875,000 litres

Proposed Design (NFPA13-2016) for Exposed Expanded Plastics stored in Open Racks with 12.2m Ceiling and 10.7m storage using Vertical Barriers at 5m Intervals.

Proposed K-16.8 ESFR & N252 In Rack

Bar

LPM/spr

No. of sprs . calculated

Hose Stream in LPM

System Demand in LPM

3.4

450

12

946

5,405+

4.14

738

15

946

12,016+

NFPA 13 K-25 ESFR Pendent

For comparison: Actual water demands will be higher based upon hydraulic calculations. On this basis total water saving would be +/- 396,660 litres

After K25 ESFR with Vertical Barrier

After N-252 EC with Horizontal Barrier

Second Phase of Testing Cartoned Unexpanded, Group A Plastics Primary Goals:  To reduce the number of in-rack sprinklers when compared to standard in-rack schemes and to reduce water demands.  To have a significant reduction of water demand for buildings up to 14.63m (48’) high that can currently be protected by ceiling-only sprinklers.  Protect buildings higher than 14.63m (48’) with low water demands.  Retrofit existing facilities, where the storage commodities or methods of storage have changed, without changing the existing sprinklers and/or increasing water flows or pressures.

Test 2 with Cartoned Unexpanded Plastics Objective:  By using a horizontal barrier at 9.1m, the total water demand and pressure would be lower than existing ceiling-only sprinkler designs.  Protect buildings higher than 14.63 with one level of in-rack sprinklers. Test 2 Ceiling Height

14.63m

Storage Height

13.11m on double row racks

Horizontal Barrier

1 at the 9.1m level

Ignition Point

At upright- face (aisle)

Ceiling Sprinklers

N 252 EC 100°C pendent @ 18.2m2 and 2.07bar

In-Rack Sprinklers

N 252 EC 100°C pendent @ 2.07bar

Ceiling Spr. Operated

1 @ 3.01 minutes

In-Rack Spr. Operated

2 - 1st @ 2.53 last @ 2:59

Peak Steel Temp – Ceil.

67° C

After N-252 EC with Horizontal Barrier

Proposed Design for Cartoned Unexpanded Plastics Stored in Racks up to and potentially over 14.63m with Horizontal Barriers at the 9.1m level

Ceiling N-252 EC Pendent @ 18.2m²/spr

Bar

LPM/spr

No. of sprs . calculated

System Demand in LPM

2.07

522

6

3,132+

The ceiling sprinkler design is based upon NFPA 13 and FM Global requirements for 9.1m high ceilings and ceiling-only sprinkler protection.

In-Rack N-252 EC Pendent

2.07

522

3

1,566+

For comparison: Actual water demands will be higher based upon hydraulic calculations.

The in-rack sprinkler demand would not be added to the ceiling demand because of the horizontal barrier. The total system demand would be the ceiling demand at 3,132+ LPM

N-Rack-EC System Vs. Current Approved Systems Current UL Listings / FM Approvals for 13.7m High Buildings-Class 4/Group A Plastics

Sprinkler demand

K22/K 25 ESFR @ 9.3m²

Proposed Design - N252 EC @ 18.2m²

UL 6,435+ lpm / 7,237+ lpm

3,132+ lpm

FM 7,177+ lpm / 8,088+ lpm

Hose stream demand Total demand

946 lpm

946 lpm

7,381+ lpm / 8,183+ lpm

4,078+ lpm

FM 8,123+ lpm / 9,034+ lpm Current UL Listings for 14.63m High Buildings-Class 4/Group A Plastics

Sprinkler demand Hose stream demand Total demand

K22/K 25 ESFR @ 9.3m²

Proposed Design - N252 EC @ 18.2m²

7,544 lpm / 8,093 lpm

3,132+ lpm

946 lpm

946 lpm

8,490+ lpm / 9,039+ lpm

4,078+ lpm

Potential Benefits – Up to 18.3m high buildings with 16.7m Storage using a single row of in-rack sprinklers? Future Protection for 48’+ High Buildings- Class 4/Group A Plastics K22/K 25 ESFR

Proposed Design - N252 EC @ 18.2m²

Sprinkler demand

NA

3,132+ lpm

Hose stream demand

NA

946 lpm

Total demand

NA

4,078+ lpm

ASRS - The Future of Storage Protection Tests 3, 4, & 5 24.4m/36.4m 18.3m/27.3m 12.2m/18.2m 6.1m/9.1m

Test 3 with Cartoned Unexpanded Plastics

Objective:  By using multiple horizontal barriers at 6.1m intervals, high bay buildings may be protected with fewer in-rack sprinklers. No face sprinklers and no sprinklers in transverse flues. Barrier open at transverse flue. Test 3 Ceiling Height

14.63m

Storage Height

13.11m on double row racks

Horizontal Barrier

2 – 6.1m level & 12.2m level

Ignition Point

Offset in Transverse Flue

Ceiling Sprinklers

N 252 EC pendent @ 18.2m2 and 0 bar

In-Rack Sprinklers

N 252 EC 100°C pendent @ 2.07bar

Ceiling Spr. Operated

3 – 1st @ 20.40 last @ 21.15

In-Rack Spr. Operated

5 - 1st @ 1.13 in 6.1m level. 1st in 12.2m level @ 13.40

Peak Steel Temp – Ceil.

232°C

Testing with a Continuous Barrier Across the Uprights Tests 1, 2, & 3

Tests 4 & 5

Test 4 with Cartoned Unexpanded Plastics Objective:  By using multiple continuous horizontal barriers at 6.1m intervals, high bay buildings may be protected with fewer in-rack sprinklers. No face sprinklers and no sprinklers in transverse flues. Fires may be contained and suppressed between barriers. Test 4 Ceiling Height

14.63m

Storage Height

13.11m on double row racks

Horizontal Barrier

2 – 6.1m level & 12.2m level

Ignition Point

Offset in Transverse Flue

Ceiling Sprinklers

N 252 EC pendent @ 18.2m2 and 0 bar

In-Rack Sprinklers

N 252 EC 100°C pendent @ 2.07bar

Ceiling Spr. Operated

None

In-Rack Spr. Operated

4 in 6.1m level only - 1st @ 1.26 4th @ 1.36

Peak Steel Temp – Ceil.

28°C

Test 5 with Cartoned Unexpanded Plastics Objective:  By using multiple continuous horizontal barriers at 9.1m intervals, high bay buildings may be protected with fewer in-rack sprinklers. No face sprinklers and no sprinklers in transverse flues. Fires may be contained and suppressed between barriers. Test 5 Ceiling Height

14.63m

Storage Height

13.11m on double row racks

Horizontal Barrier

1 – 9.1m level

Ignition Point

Offset in Transverse Flue

Ceiling Sprinklers

N 252 EC pendent @ 18.2m2 and 0 bar

In-Rack Sprinklers

N 252 EC 100°C pendent @ 2.07bar

Ceiling Spr. Operated

None

In-Rack Spr. Operated

3 in 9.1m level only - 1st @ 1.14 3rd @ 1.15

Peak Steel Temp – Ceil.

28°C

Fixed Camera at 6.1m Barrier Level

In Conclusion: For storage of Exposed Expanded Class A Plastics in double row, open framed racks:  By installing a horizontal barrier at the 6.1m level with the Model N252 EC Pendent, used as in-rack sprinklers, buildings up to 12.2m high will have significantly lower water demands than using ceiling-only sprinkler protection.

For storage of Cartoned Unexpanded Plastics in double row, open framed racks:  By installing a horizontal barrier at the 9.1m level with the Model N252 EC Pendent, used as in-rack sprinklers, buildings up to 14.63m high will have lower water demands than using ceiling-only sprinkler protection.  Retrofit applications where storage commodities or methods of storage have changed, adding a horizontal barrier or barriers with the Model N252 EC Pendent, used as in-rack sprinklers, may eliminate changing ceiling sprinklers or water supplies.

For storage of Cartoned Unexpanded Plastics in double row, open framed racks:  By installing continuous horizontal barriers at 6.1m to 9.1m levels with the Model N252 EC Pendent, used as in-rack sprinklers, buildings over 14.63m high may be protected while reducing the number of sprinklers required by current in-rack schemes. Fires may be contained and suppressed between barriers.  Retrofit applications of high bay buildings where storage commodities or methods of storage have changed, adding continuous horizontal barriers with the Model N252 EC Pendent, used as in-rack sprinklers, may eliminate changing ceiling sprinklers or water supplies while greatly reducing the quantity of in-rack sprinklers.