INCH-POUND

MIL-DTL-32235/3A

30 March 2021

W/Change 01 31 March 23 ES23-016 (DSCP-SS-23-00300)

SUPERSEDING

MIL-DTL-32235/3

15 September 2010

DETAIL SPECIFICATION SHEET

UNITIZED GROUP RATION-EXPRESS (UGR-E) HEATER MODULE:

BOIL-IN-BAG (BIB) MODULE

This specification is approved for use by all

Departments and Agencies of the Department of Defense.

The requirements for acquiring the product described herein shall consist of this specification 

sheet and MIL-DTL-32235.

REQUIREMENTS

I. Boil-In-Bag (BIB) module.

The BIB module shall consist of a fiberboard box containing one BIB of dry or 

dehydrated food packaged in a barrier pouch, one pouch of potable water for rehydrating the 

food, one heater packaged in a barrier pouch, one activation fluid unit, and one serving tray 

in a polyethylene bag. Note that the terms bag and pouch are used interchangeably.

 A. Heater.

The BIB heater shall be constructed of materials that, when activated by a fluid, shall 

initiate and propagate an exothermic reaction suitable for use with food. This reaction shall 

generate adequate heat to completely cook the food when applicable, or heat the food to a 

safe serving temperature. No toxic gas, liquid or solid by-products are desirable. If toxic byproducts are produced, they shall be of the least severity and smallest amount possible while 

allowing for adequate heating and ensuring operator and consumer safety. When low 

hydrogen generating heater is used, it shall generate less than 30 liters of hydrogen in 60 

minutes. The heater material shall be evenly distributed and completely sealed within the 

scrim matrix of the heater to minimize the release of materials, and facilitate direct in-place 

activation of the heater materials. The heating rate shall be optimized to minimize the time 

required to heat the food, yet not cause excessive foaming or uncontrolled release of reaction 

by-products. The BIB heater and barrier material shall not melt, deform or degrade during 

heating.
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AMSC N/A FSC 8970

The heater is activated by the addition of a fluid that shall fully activate the heater 

material. The non-woven porous polymeric scrim shall be sealed and sized to accommodate 

proper fit and function of the heater module. Each heater (heater elements in a matrix) shall 

be correctly and legibly labeled in accordance with MIL-DTL-32235.

One heater shall be packaged in a barrier pouch constructed from laminated material, 

with one lamina a minimum of 0.00035 inch thick aluminum foil. The barrier pouch shall be 

heat sealed on all four edges. A tear nick, notch or serrations shall be provided to facilitate 

opening of the filled and sealed barrier pouch. The barrier pouch shall have maximum outer 

dimensions of 11 by 15 inches. Each barrier pouch with heater shall be correctly and legibly 

labeled in accordance with MIL-DTL-32235. In addition, the following statement shall be 

labeled on the barrier pouch and all boxes, as applicable:

FLAMELESS HEATER – DO NOT CONSUME

NOTE: Any hazard markings required for Occupational Safety and Health 

Administration (OSHA), U.S. Environmental Protection Agency (USEPA) and U.S. 

Department of Transportation (USDOT) compliance are to be labeled on the barrier pouch 

and all boxes, as applicable.

 B. Activation fluid unit.

The activation fluid unit consisting of a pouch containing the activation fluid shall be 

made of material equivalent to Class 1 of MIL-PRF-131. Alternate activation fluid unit 

materials and design shall be permitted with approval from Combat Capabilities 

Development Command (DEVCOM) Soldier Center. The pouch shall be designed with a 

center or side spout and shall have maximum outer dimensions of 9-1/2 by 14 inches. The 

pouch shall be filled with 1.5 percent saline (water and sodium chloride) solution, or as 

specified by the heater manufacturer with approval from Combat Capabilities Development 

Command (DEVCOM) Soldier Center. The volume of fluid in the pouch, when combined 

with the heater, shall be adequate to initiate and propagate the exothermic reaction.

The pouch shall be heat sealed on all edges. A tear nick, notch or serrations shall be 

provided in the spout area to facilitate opening of the filled and sealed pouch. The average 

seal strength of the closure seal shall be not less than 6 pounds per inch of width and no 

individual specimen shall have a seal strength of less than 5 pounds per inch of width. 

Alternatively, the filled and sealed pouch shall exhibit no rupture or seal separation greater 

than 1/16 inch or seal separation that reduces the effective closure seal width to less than 1/16 

inch when tested for internal pressure resistance.

Each activation fluid unit shall be correctly and legibly labeled in accordance with 

MIL-DTL-32235. In addition, the following statement shall be labeled on the pouch:

ACTIVATION FLUID - DO NOT CONSUME
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NOTE: Any hazard markings required for Occupational Safety and Health 

Administration (OSHA), U.S. Environmental Protection Agency (USEPA) and U.S. 

Department of Transportation (USDOT) compliance are to be labeled on the activation fluid 

unit and all boxes, as applicable.

 C. Boil-In-Bag (BIB).

The BIB of food shall meet the requirements of the applicable food document. Note 

that the requirements for eggs in a BIB are cited in PCR-E-017, Egg Mix, Reduced 

Cholesterol, Pasteurized, Uncooked, Dehydrated, Packaged in a Boil-In-Bag (BIB).

 D. Rehydration water pouch.

Water shall conform to all requirements of A-A-20332. The water shall be sterilized 

by either class 1 (thermoprocessed), class 2 (ozone), class 3 (ultraviolet light), or class 4 (hot 

fill) treatment.

The pouch containing the rehydration water shall be made of material equivalent to 

Class 1 of MIL-PRF-131. The pouch shall have maximum outer dimensions of 11 by 14 

inches. The minimum volume of rehydration water in the pouch shall be 1.5 1.3 liters (51 44

fluid ounces). The pouch shall be fitted with a cap with a 3/4 inch opening and a tamper 

evident closure. The pouch shall not leak.

The pouch shall be heat sealed on all edges. The average seal strength of the closure 

seal shall be not less than 6 pounds per inch of width and no individual specimen shall have a 

seal strength of less than 5 pounds per inch of width. Alternatively, the filled and sealed 

pouch shall exhibit no rupture or seal separation greater than 1/16 inch or seal separation that 

reduces the effective closure seal width to less than 1/16 inch when tested for internal 

pressure resistance.

Each pouch shall be correctly and legibly labeled. The label shall contain the 

following information:

(1) Name

(2) Contents

(3) Net volume

(4) Date of pack 1/

(5) Contractor's name and address 

1/ Each pouch shall have the date of pack noted by using a four digit code beginning with the 

final digit of the current year followed by the three digit Julian day code. For example, 14 

February 2030 would be coded as 0045. The Julian day code shall represent the day the water

was packaged.
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 E. Serving tray.

The serving tray shall be constructed from food grade (direct food contact), water 

resistant paperboard. All inside surfaces and edges shall be coated. The serving tray shall be 

capable of containing the food product during the preparation, cooking and serving of the 

food. There shall be no product transfer in or out of serving tray. The dimensions shall be a 

maximum of 14-1/2 by 10 by 2 inches. The serving tray shall be placed in a polyethylene bag 

with dimensions of approximately 24 12 by 16 inches and the bag sealed. The polyethylene 

bag shall be labeled with:

SERVING TRAY

DO NOT DISPOSE

REMOVE BAG BEFORE USING

 F. Fiberboard box.

The fiberboard box shall be constructed from C flute corrugated fiberboard. The 

inside of the box shall be coated with a food grade (direct food contact), water resistant 

coating.

The design of the box shall be a flip top box with a locking mechanism. The outside 

dimensions shall be a maximum of 15-1/2 by 11 by 2-3/4 inches. The fiberboard box shall 

maintain its shape and integrity while containing the activated, heated, and cooked or serving 

temperature of BIB food for a minimum of 90 minutes after the heating reaction is initiated.

 G. Assembly of BIB module.

The BIB module shall consist of one fiberboard box containing one BIB of food, one 

pouch of rehydration water, one activation fluid unit, one packaged heater, one serving tray 

in a polyethylene bag, and instruction sheets. All components shall be compatible and shall 

fit in the module box. Each heater module shall be correctly and legibly labeled in 

accordance with MIL-DTL-32235.

EXAMINATION

 A. BIB heater module examination. The finished product shall be examined for 

conformance with the requirements specified in MIL-DTL-32235 and this specification 

sheet. The BIB heater module shall be examined for the defects listed in Table I.
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TABLE I. BIB heater module defects 1/ 2/ 3/

Category Defect

Major Minor

101 Heater module not a BIB heater module.

102 Heater does not contain materials that will initiate and propagate an 

exothermic reaction.

103 Heater causes excessive foaming or uncontrolled release of reaction

by-products.

104 Heater not correct size or not correct capacity.

105 Heater module does not generate adequate heat to completely cook the 

food when applicable, or heat the food to a safe serving temperature. 4/

201 Tear nick or notch or serrations on heater barrier pouch missing or does 

not facilitate opening.

106 Heater not packaged in a barrier pouch.

202 Tear nick or notch or serrations on activator fluid pouch missing or does 

not facilitate opening.

107 Rehydration water pouch leaks.

108 Serving tray not correct dimensions or not correct design.

109 Serving tray not in polyethylene bag.

203 Fiberboard module box not correct dimensions or not correct design.

204 Fitment on pouch of rehydration water not compatible with BIB.

205 Components not compatible or do not fit in fiberboard module box.

206 Fiberboard box does not maintain its shape and integrity while 

containing the activated, heated, and cooked or serving temperature of 

BIB food for a minimum of 90 minutes after the heating reaction is 

initiated.

207 Low hydrogen generating heater generates more than 30 liters of 

hydrogen in 60 minutes.
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1/ Requirements that rehydration water meets A-A-20332 shall be verified by Certificate of 

Conformance (CoC).

2/ Serving tray construction from fiberboard with a food grade water resistant coating shall 

be verified by CoC.

3/ The low hydrogen generating heater shall be verified by CoC.

4/ BIB Eggs must be cooked to an internal temperature of 145 ̊F (63 ̊C) for fifteen seconds.

Polymeric food trays must be reheated to an internal temperature of at least 135 ̊F (57 ̊C).

PART IDENTIFIERS AND SOURCES OF SUPPLY

1. Heater. The heater is available from:

Luxfer Magtech Incorporated

2940 Highland Avenue

Cincinnati, OH 45212

(800) 503-4483

2. Heater barrier pouch. The barrier pouch material is available from:

Winter-Wolff International

131 Jericho Turnpike

Jericho, NY 11753

(516) 997-3300

3. Activation fluid unit. The activator pouch is identified as Part # UGR-E-AFU-GEN 

II The material equivalent to Class 1 of MIL-PRF 131 for the construction of the activation 

fluid unit pouch is available from:

Cadillac Products Packaging Company

5800 Crooks Road

Suite 200

Troy, Michigan 48098-2830 

(800) 837-0055

The filled and sealed activation fluid units are available from:

Heritage Packaging

625 Fishers Run

Victor, NY 14564
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(585) 742-3310

4. Thermocoupled BIBs. Filled thermocoupled BIBs or instructions on how to 

construct them are available from:

Combat Capabilities Development Command (DEVCOM) Soldier Center

FCDD-SCD-SCR

10 General Greene Avenue

Natick, MA 01760-5000

(508) 206-3410

5. Instruction sheets. The following operation instruction sheets are attached:

FIGURE 1. UGR-E BIB Operating Instructions, for Heater with Hydrogen 

Generating Warning

FIGURE 2. UGR-E BIB Operating Instructions, for Heater with Low/No Hydrogen 

Generating Warning

FIGURE 3. Instructions for UGR-E Eggs, for Heater with Hydrogen Generating 

Warning

FIGURE 4. Instructions for UGR-E Eggs, for Heater with Low/No Hydrogen 

Generating Warning

Instruction sheets in color are available electronically from: 

Combat Capabilities Development Command (DEVCOM) Soldier Center

FCDD-SCD-SCR

10 General Greene Avenue

Natick, MA 01760-5000

(508) 206-3410

REFERENCES

DEPARTMENT OF DEFENSE SPECIFICATIONS

MIL-DTL-32235 - Unitized Group Ration – Express (UGR-E) Heater 

Module, General Specification for

MIL-PRF-131 - Barrier Materials, Watervaporproof, Greaseproof, 

Flexible, Heat-Sealable
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A-A-20332 - Water, Emergency, Drinking

(Copies of these documents are available online at https://quicksearch.dla.mil.)

PCR-E-017 - Egg Mix, Pasteurized, Uncooked, Dehydrated, 

Packaged in a Boil-In-Bag (BIB)

(Copies of this document are available from Combat Capabilities Development Command 

(DEVCOM) Soldier Center, FCDD-SCD-SCR, 10 General Greene Avenue, Natick, MA 

01760-5000.)

GOVERNMENT PUBLICATIONS

U.S. DEPARTMENT OF LABOR

Occupational Safety and Health Administration (29 CFR Part 1910, Subpart H)

(Copies of this document are available online at http://www.osha.gov or U.S. Department of 

Labor Occupational Safety & Health Administration, 200 Constitution Avenue, N.W., Room 

Number N3626, Washington, D.C. 20210.

U.S. DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration (49 CFR Parts 171-180)

(Copies of this document are available online at https://www.fmcsa.dot.gov or 

Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402-

0001.)

U.S. ENVIRONMENTAL PROTECTION AGENCY

Resource Conservation and Recovery Act (40 CFR, Parts 239-282)

(Copies of this document are available online at http://www.epa.gov or from the 

Superintendent of Documents, ATTN: New Orders, P.O. Box 371954, Pittsburgh, PA 15250-

7954.)
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FIGURE 1. UGR-E BIB Operating Instructions, for Heater with Hydrogen Generating

Warning
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FIGURE 1. UGR-E BIB Operating Instructions, for Heater with Hydrogen Generating 

Warning
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FIGURE 2. UGR-E BIB Operating Instructions, for Heater with Low Hydrogen

Generating Warning
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FIGURE 2. UGR-E BIB Operating Instructions, for Heater with Low/No Hydrogen 

Generating Warning
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FIGURE 3. Instructions for UGR-E Eggs, for Heater with Hydrogen Generating 

Warning
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FIGURE 3. Instructions for UGR-E Eggs, for Heater with Hydrogen Generating Warning 
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FIGURE 4. Instructions for UGR-E Eggs, for Heater with Low Hydrogen Generating

Warning
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FIGURE 4. Instructions for UGR-E Eggs, for Heater with Low/No Hydrogen Generating 

Warning
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Custodians: Preparing activity:

Army – GL Army – GL

Navy – SA (Project 8970-2021-005)

Air Force – 35

Review Activities:

Army – MD, QM

Navy – MC

DLA – SS

NOTE: The activities listed above were interested in this document as of the date of this 

document. Since organizations and responsibilities can change, you should verify the 

currency of the information above using ASSIST Online database at https://assist.dla.mil.