Low Temperature Ignition of Wood

Presented by

Jeffery H. Warren, Ph.D., P.E., CSP, C.F.E.I.

Clemson, SC : 4:11 AM- November 11, 1998

Clemson, SC Fire: 11/11/1998Startup: 2/18/97

Typical Installation

2 by 6 studs

Cement Board

Stainless Steel Sheet

2 by 6 or 2 by 12 Blocking

Clemson, SC

Bent mounting bracket

Bracket Pre-Fire Position Held In Place By Pipe

Wall CavityIntact Durock

Mounting Bracket Detail

Clemson, SC

Mounting Bracket

Clemson, SC

Intact Sheathing

Fire Origin

Wood Blocking

Clemson, SC- Back of Cheemelter

Extensive Heat Damage

Clemson, SC

Fire Origin

Blocking Remains

Durock

Trussville, Al Inspection 3/10/99Startup Date: 3/10/1999

Trussville, Al

DurockSheathing

Wood Blocking

Trussville, Al

Niceville, Florida Inspection 3/26/1999Startup Date: 9/30/97

Heat Damage

Niceville, Florida

Tullahoma, Tennessee Inspection: 4/7/1999Startup Date: 11/19/1996

Heat Damage

Tullahoma, Tennessee

Tullahoma, Tennessee

Left Most Bolt Hole

Tullahoma, Tennessee

Heat Damage

Tullahoma, Tennessee

Tullahoma, Tennessee

The Warren Group Laboratory

Maximum Temperature Distributions in Wall at Point A

Inside of

Cheese

Melter

Back of

Cheese

Melter

Bolt Head

Location

Betw een

Stainless

Steel &

Duroc

Front of 2 x

12 Wood

Blocking

Back of 2 x

12 Wood

Blocking

Interior

Surface of

Back Wall

Panel

Location in Wall

Tem

pera

ture

F

Test 1: Cheese Melter

Test 2: Cheese Melter & Steak Grill

Test 3: Cheese Melter & Fryer w ith Water

Test 4: Cheese Melter & Fryer w ith Grease

Test 1

• Cheesemelter Operating alone

• Run at Highest Temperature

• Length of run 9 hours 45 minutes

• Maximum Temperature at Front of 2 by 12 Blocking

• 115 Deg F

Test 2

• Cheesemelter Operating with Steak Grill/ Hood On

• Run at Highest Temperature 3h 45 min• Steak Grill Turned Off with Hood On 1 h• Hood off, Cheesemelter on 3 hr• Max Temp at Front of 2 by 12 Blocking- 265

Deg F• Max average Temperature in Block- 256 Deg F

Test 3

• Cheesemelter Operating with Deep Fat Fryer/ Hood On

• Deep Fat Fryer Filled with Water • Water Boiled at 212 Deg F• Deep Fat Fryer High Temp Sensor Never hit 375 Deg

F Temp Setting• Gas Burner Ran Continuously 1 hr 45 min• Max Temp 370 Deg F• Unrealistic

Test 4

• Cheesemelter Operating with Deep Fat Fryer/ Hood On

• Deep Fat Fryer Filled with Peanut Oil and Product• Product Frozen Chicken Breasts, shrimp, scallops

and French Fries• Test Run 7 h 45 min• Temps up and down depending on Product• More Often with 2.5 lbs fries every 4 min and 4

chicken breast cooking over 10 minutes

Test 4 (cont’d)

• Max wall temp at front of 2 by 12 was 307 Deg F

• Max Avg Block Temp was 296 Deg F

Test Stand

Test Stand

Test 5

• Cheesemelter Operating with Deep Fat Fryer/ Hood On

• Cheesemelter mounted on Sand• Temp directly behind stand was 253 F

Summary - Testing

• Cheesemelter 115 deg F

• Cheesemelter and Steak Grill 260 deg F

• Cheesemelter and Deep Fat Fryer 307 deg F

Sebring, FL

Fig 28

Lag Bolt HolesLag Bolt Holes

104 34A.jpg appendix 12 Report 60093

139_31.jpg

Lag Bolts

100 30A.jpg

147_29.jpg

009_6.jpg

Report 60093

Left Mounting BracketRight Mounting Bracket

Gas Control Valve Knob

Who has the first question?