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.

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

Test Parameters.

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

Reliable Model N252-EC Extended

Coverage Pendent Sprinkler

100mm clearance above commodity

50mm deflector distance below beam

Target

Array

Spray Pattern @ 2.07bar

1200mm

aisle

width

N252-EC Sprinklers

Centred in Longitudinal Flue and Centred Between Rack

Uprights = 2,515mm on centre.

Installation Method.

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.

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

Results.

After N-252 EC

with

Horizontal

Barrier

Proposed Design

Ceiling Temp(C) Bar LPM/spr No. of sprs

.

calculated

System

Demand in

LPM

K-16.8 ESFR 100° 3.4 450 12 5,405+

In-Rack

N-252 EC

Pendent

100° 2.07 522 3 1,567+

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

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

Proposed Bar LPM/spr No. of sprs

.

calculated

Hose

Stream in

LPM

System

Demand in

LPM

K-16.8 ESFR &

N252 In Rack

3.4 450 12 946 5,405+

FM DS 8-9

K-25 ESFR

Pendent

5.17 829 20 1,893 18,473+

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

Existing Ceiling Sprinkler Design (FM) for

Exposed Expanded Plastics stored in Open Racks

with 12.2m Ceiling and 10.7m storage.

Proposed Bar LPM/spr No. of

sprs .

calculated

Hose

Stream in

LPM

System

Demand in

LPM

K-16.8 ESFR &

N252 In Rack

3.4 450 12 946 5,405+

NFPA 13

K-25 ESFR

Pendent

4.14 738 15 946 12,016+

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

calculations. On this basis total water saving would be +/- 396,660 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.

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 Bar LPM/spr No. of

sprs .

calculated

System

Demand in

LPM

N-252 EC Pendent @

18.2m²/spr

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+

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

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

Current UL Listings for 14.63m High Buildings-Class 4/Group A Plastics

K22/K 25 ESFR @ 9.3m² Proposed Design - N252 EC @

18.2m²

Sprinkler demand 7,544 lpm / 8,093 lpm 3,132+ lpm

Hose stream demand 946 lpm 946 lpm

Total demand 8,490+ lpm / 9,039+ lpm 4,078+ lpm

Current UL Listings / FM Approvals for 13.7m High Buildings-Class 4/Group A Plastics

K22/K 25 ESFR @ 9.3m² Proposed Design - N252 EC @

18.2m²

Sprinkler demand UL 6,435+ lpm / 7,237+ lpm 3,132+ lpm

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

Hose stream demand 946 lpm 946 lpm

Total demand 7,381+ lpm / 8,183+ lpm 4,078+ lpm

FM 8,123+ lpm / 9,034+ lpm

N-Rack-EC System Vs. Current Approved

Systems

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

Potential Benefits – Up to 18.3m high

buildings with 16.7m Storage using a

single row of in-rack sprinklers?

ASRS - The Future of

Storage Protection

Tests 3, 4, & 5

6.1m/9.1m

18.3m/27.3m

12.2m/18.2m

24.4m/36.4m

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.