INCH-POUND

MIL-PRF-32004C

27 January 2017

SUPERSEDING

MIL-PRF-32004B

29 October 2003

PERFORMANCE SPECIFICATION

PACKAGING OF FOOD IN POLYMERIC TRAYS

This specification is approved for use by all Departments and Agencies of the Department 

of Defense.

1. SCOPE

1.1 Scope. This specification covers the performance criteria for packaging materials and 

the packaging of food in polymeric trays to include the filling and hermetic sealing of the 

tray, the processing of the filled and sealed tray, and the application of a protective sleeve for 

the tray and lid. The combination of the tray and tray lid is referred to as the container.

1.2 Classification. The packaged and processed products will be of the following types as 

specified (see 6.1).

1.2.1 Types. Packaged and processed types are as follows:

Type I - Retortable products

Style A – With protective sleeve

Style B – With fiberboard pad for shipment to ration assembler

Type II - Oven-baked products 

Comments, suggestions, or questions on this document should be addressed to: US Army 

Research, Development and Engineering Command, Natick Soldier Research, Development 

and Engineering Center, RDNS-SEC-EMR, 10 General Greene Avenue, Natick, MA 

01760-5018 or emailed to elizabeth.r.painter2.civ@mail.mil. Since contact information can 

change, you may want to verify the currency of this address information using the ASSIST 

Online database at https://assist.dla.mil/.

AMSC N/A FSC 89GP

DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.
MIL-PRF-32004C

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 2. APPLICABLE DOCUMENTS

 2.1 General. The documents listed in this section are specified in section 4 of this 

specification. This section does not include documents cited in other sections of this 

specification or recommended for additional information or as examples. While every effort 

has been made to ensure the completeness of this list, document users are cautioned that they 

must meet all specified requirements documents cited in section 4 of this specification, 

whether or not they are listed.

 2.2 Government documents. None.

 2.3 Non-Government publications. The following documents form a part of this document 

to the extent specified herein. Unless otherwise specified, the issues of these documents are 

those cited in the solicitation or contract.

 ASTM INTERNATIONAL (ASTM)

D999 - Standard Methods for Vibration Testing of Shipping Containers

D1974/D1974M - Standard Practice for Methods of Closing, Sealing and Reinforcing 

 Fiberboard Boxes

D3985 - Standard Test Method for Oxygen Gas Transmission Rate Through 

 Plastic Film and Sheeting Using a Coulometric Sensor

D5118/D5118M - Standard Practice for Fabrication of Fiberboard Shipping Boxes

D5276 - Standard Test Method for Drop Test of Loaded Containers by Free Fall

F1249 - Standard Test Method for Water Vapor Transmission Rate Through 

 Plastic Film and Sheeting Using a Modulated Infrared Sensor

(Copies of these documents are available online at http://www.astm.org/Standard/ or from 

ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.)

 2.4 Order of precedence. In the event of a conflict between the text of this document and 

the references cited herein, the text of this document takes precedence. Nothing in this 

document, however, supersedes applicable laws and regulations unless a specific exemption 

has been obtained.

 3. REQUIREMENTS

 3.1 Performance characteristics.

 3.1.1 Tray configurations and dimensions. Tray material shall be fabricated into trays as 

specified in figure 1. The tray shall have a minimum capacity of 96 fluid ounces.
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 3.1.2 Oxygen gas transmission rate.

 3.1.2.1 Tray material. The oxygen gas transmission rate (O2GTR) of the material shall not 

exceed 0.01 cubic centimeters (cc)/mil/100 square inch (sq. in.)/24 hours (hrs.).

 3.1.2.2 Tray lid. The O2GTR of the material shall not exceed 0.0039 cc/100 sq. in./24 hrs.

 3.1.3 Water vapor transmission rate.

 3.1.3.1 Tray material. The water vapor transmission rate (WVTR) of the material shall not 

exceed 0.69 gram (gm)/mil/100 sq. in./24 hrs.

 3.1.3.2 Tray lid. The WVTR of the material shall not exceed 0.00064 gm/100 sq. in./24 

hrs.

 3.1.4 Processing. The tray and lid material shall be capable of withstanding the process 

specified in the applicable food document.

 3.1.5 Lid material. The lid material shall be capable of hermetically sealing the tray filled 

with product.

 3.1.6 Protective sleeve (Type I, Style A). The sleeve shall protect the tray, lid, and seals 

from physical damage. The maximum height of the filled, sealed and processed tray with 

protective sleeve shall not exceed 2-1/8 inches. The length of the protective sleeve shall 

cover the entire tray flange, and shall not exceed 12-13/16 inches. The width of the protective 

sleeve shall fit snugly against the tray flange so as to restrict the sliding motion of the tray 

within the sleeve. The top and bottom faces of the sleeve at the open ends shall be 

compressed in such a manner so as to keep the top sleeve face flush against the tray lid and 

seams (see 6.4). The tray shall be restrained within the sleeve, at both ends, in such a manner 

so as to prevent the tray from sliding out. The sleeve shall provide added stacking strength to 

the tray. The color of all inside and outside surfaces of the sleeve shall be natural kraft, tan, 

or dull gray. A label with the following instructions shall be printed, stamped, or otherwise 

applied onto the protective sleeve, in a manner that does not damage the sleeve, with 

permanent ink of any contrasting color. Type size of the label shall be no smaller than shown 

below (printed on 8-1/2 inch x 11inch paper), but can be larger.
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ATTENTION!

PROTECTIVE SLEEVE-DO NOT THROW AWAY

SAVE AND RE-USE TO PROTECT

TRAY FROM DAMAGE

To Avoid Damaging Tray Lid:

 1. Keep This Protective Sleeve Secured to

 Tray Until Ready to Heat, Then Remove.

 2. Insert Tray Back Into Sleeve After Heating.

 3. Always Use Sleeves When Transporting

 Trays in Insulated Food Containers.

 4. If Sleeves Are Unavailable, Stack Trays

 Lid-to-Lid with Fiberboard Pads in Between.

 3.1.7 Fiberboard pad (Type I, Style B and Type II). The fiberboard pad shall protect the 

tray, lid and seals from physical damage. Fiberboard pads shall be placed between the trays 

and on the top and bottom of the stacked trays. The pad dimensions shall be not less than 1/8 

inch of the full length and width of the inside dimensions of the box and shall be fabricated 

of class D, burst grade 275 fiberboard or stronger. The color of the fiberboard pad shall be 

natural kraft, tan, or dull gray.

 3.1.8 Rough handling survivability. After processing, four filled and sealed polymeric 

trays shall be packed with sleeves in a fiberboard shipping container and shall be capable of 

withstanding rough handling.

 3.1.9 Headspace.

 3.1.9.1 Residual gas (Type I only). Residual gas volume in the filled, sealed and processed 

trays shall not exceed 250 cc.

 3.1.9.2 Vacuum (Type II only). The filled and sealed polymeric tray shall show evidence 

of vacuum.

 3.1.10 Closure seal. The closure seal, defined as the width of fusion bonded seal at any 

point perpendicular to the tray flange along the tray perimeter, shall be not less than 1/8 inch 

wide. The first 1/16 inch of the seal at the food product edge shall be free of defects or 
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anomalies, such as, but not limited to entrapped matter, moisture or grease. The closure seal 

shall be continuous along the tray flange surface. The closure seal shall be free of impression 

or design on the seal surface and free of wrinkles.

 3.1.11 Internal pressure.

 3.1.11.1 Destructive. The filled, sealed and processed trays shall withstand an internal 

pressure of 20 pounds per square inch gauge (psig).

 3.1.11.2 Non-Destructive (Type I only). The filled, sealed and processed trays shall 

withstand a compression force of 1,400 pounds.

 3.1.12 Lid opening. The tray lid shall be easily removed with a knife.

 3.1.13 Camouflage. The color of exterior surfaces of the tray and tray lid shall contribute 

to woodland camouflage (e.g., earth brown, black, olive drab, forest green, etc.).

 4. VERIFICATION

 4.1 Conformance inspection. Conformance inspection includes those examinations and 

tests from table I, as defined in the contract or purchase order, performed on specified 

samples (see 6.1).

TABLE I. Verification methods

Characteristic 1/ Requirement Verification

Tray configurations and dimensions 3.1.1 4.3.1

Oxygen gas transmission rate 3.1.2 4.3.2

Water vapor transmission rate 3.1.3 4.3.3

Processing 3.1.4 4.3.4

Lid material 3.1.5 4.2

Protective sleeve (Type I, Style A only) 3.1.6 4.3.5

Fiberboard pad (Type I, Style B and Type 

II)

3.1.7 4.3.6

Rough handling survivability 3.1.8 4.3.7

Headspace 3.1.9 4.3.8
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TABLE I. Verification methods - Continued

Characteristic 1/ Requirement Verification

Residual gas (Type I only) 3.1.9.1 4.3.8.1

Vacuum (Type II only) 3.1.9.2 4.3.8.2

Closure seal 3.1.10 4.2

Internal pressure 3.1.11 4.3.9

Destructive 3.1.11.1 4.3.9.1

Non-Destructive (Type I only) 3.1.11.2 4.3.9.2

Lid opening 3.1.12 4.3.10

Camouflage 3.1.13 4.3.11

1/ In lieu of testing, determination of compliance to camouflage requirements may be 

ascertained by examination of records, invoices, or other valid documents. In addition, 

compliance to the requirements for O2GTR, WVTR, processing, rough handling 

survivability, outside tray dimensions, stacking strength of sleeve, lid opening, and tray 

capacity may be verified by Certificate of Conformance.

 4.2 Examination of container. After processing, the container shall be visually examined 

for compliance with 3.1.4, 3.1.5, and 3.1.10. Defects and defect classifications are listed in 

table II.

TABLE II. Filled, sealed and processed container defects 1/

Category Defect

Critical Major A Major B Minor

General

1 Swollen container.

2 Tear, crack, cut, hole, or if a multi-layered laminate

is used, abrasion through more than one layer of the

tray or through the barrier (e.g., foil) layer of the lid 

material or leakage through any seal or surface.

3 Closure seal not continuous along tray flange surface.
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TABLE II. Filled, sealed and processed container defects 1/ - Continued

Category Defect

Critical Major A Major B Minor

4 Foldover wrinkles extending into the seal such that

the closure seal is reduced to less than 1/8 inch.

5 Presence of delamination when a multi-layered 

laminate is used. 2/

101 Unclean container. 3/

102 Any impression or design on the seal surfaces which 

conceals or impairs visual detection of seal defects.

151 Presence of delamination when a multi-layered 

laminate is used. 2/

201 Presence of delamination when a multi-layered 

laminate is used. 2/ 7/

202 Color does not contribute to woodland camouflage.

203 Presence of any permanent tray body deformation, 

such that deformed area is discolored and roughened

in texture.

204 Closure seal not free of wrinkles along the seal area 

that span the entire width of seal. 4/ 7

Type I - Retortable products

6 Abrasion on the lid material within 1/16 inch of food 

product edge of seal such that barrier (e.g., foil) layer 

of the lid material is exposed. 7/

7 Presence of entrapped matter within 1/16 inch of the 

food product edge of seal or entrapped moisture or 

grease within 1/16 inch of the food product edge of

seal that results in less than 1/16 inch of defect free 

seal width at the outside edge. 5/ 7/

103 Closure seal width less than 1/8 inch. 6/ 7/
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TABLE II. Filled, sealed and processed container defects 1/ - Continued

Category Defect

Critical Major A Major B Minor

205 Presence of any seal defect or anomaly (e.g.,

entrapped moisture, gases, etc.) within 1/16 inch of 

food product edge of seal. 5/ 7/

Type II – Oven-baked products

8 Closure seal width less than 1/16 inch. 6/

9 Presence of entrapped matter (e.g., crumbs, topping, 

etc.) within seal area that results in less than 1/16 inch 

of continuous defect free seal width at any point 

perpendicular to the tray flange.

206 Closure seal width less than 1/8 inch. 6/

1/ The following procedure may be used by inspection personnel to examine for filled,

sealed and processed container defects on a consistent basis:

1. Remove tape from one end of protective sleeve only.

2. Remove tray from open end of protective sleeve.

3. Observe interior of sleeve for signs of food product/wetness as this may indicate a

potential defect.

4. Observe all sides of tray/lid for obvious leaks.

5. Set tray on flat surface, lid up and observe for apparent swelling. As there is a 

maximum for allowable residual gas requirement, appearance of the lid should 

typically range from flush with the surface of the tray flanges to somewhat concave 

from applied vacuum.

6. With the tray still on a flat surface, press down on the lid with both hands (palms 

down) and apply a medium force (e.g., 30-40 pounds). Listen and look for signs of air 

or food product leakage.

7. Examine lid surface for cuts, holes, leaks, abrasions, seal width, continuous seals, etc.

Focus attention to where the lid body interfaces the seal area. If the lid material 

overhangs the tray flange at the outer edges, lift lid material slightly and examine where 

the underside of the lid contacts the tray flange. This area may be slightly wetted if a noncontinuous seal or other defect is present.

8. Hold tray with lid down and examine the tray body for holes, cuts, cracks, etc. or any 

areas where wet or dry food product is apparent.

9. Record any defects in accordance with table II above.

10. Re-insert tray into sleeve and re-tape.

2/ Delamination defect classification:
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Critical - Evidence of outer ply delamination such that the adjacent ply in the lid body is 

exposed or evidence of multi ply delamination such that the food contact layer is exposed. 

Any evidence of outer ply delamination of the tray body or internal layer separation within 

the tray body due to, (for example) poor adhesion between layers.

Major B - Delamination of the outer ply in the lid seal area that can be propagated to 

expose the adjacent ply at the food product edge of the lid. The separated outer ply shall be 

grasped between thumb and forefinger and gently lifted toward the food product edge of the 

seal or if the separated area is too small to be held between thumb and forefinger, a number 

two stylus shall be inserted into the delaminated area and a gentle lifting force applied 

against the outer ply. If separation of the outer ply can be made to extend to the product edge 

of the seal with no discernible resistance to the gentle lifting, the delamination shall be scored 

as a Major B defect. Additionally, spot delamination of the outer ply in the body of the lid 

that can be propagated beyond its initial borders is also a Major B defect. To determine if the 

delaminated area is a defect, use the following procedure: Mark the outside edges of the 

delaminated area using a bold permanent marking pen. Open the tray and remove the 

contents. Cut the lid on opposing sides of the delaminated area not closer than 3/16 inch from 

the delaminated area. Hold the delaminated area between the thumb and forefinger of each 

hand with both thumbs and forefingers touching each other. The delaminated area shall then 

be rapidly flexed 10 times by rotating both hands in alternating clockwise-counter clockwise 

directions. After flexing, the separated outer ply shall be grasped between thumb and 

forefinger and gently lifted away from the lid surface or if the separated area is too small to 

be held between thumb and forefinger, a number two stylus shall be inserted into the 

delaminated area and a gentle lifting force applied against the outer ply. Any propagation of 

the delaminated area, as evidenced by the delaminated area exceeding the limits of the 

outlined borders, shall be scored as a Major B defect.

Minor - Minor delamination of the outer ply in the lid seal area is acceptable and shall not 

be classified as a minor defect unless it extends to within 1/16 inch of the food product edge 

of the seal. Isolated spots of delamination in the body of the lid that do not propagate when 

flexed as described above shall be classified as minor. Post-retort wrinkling of the outer ply 

in the lid seal area shall also be scored as a minor defect. Note: Post-retort wrinkles of the 

outer ply are typically perpendicular to the flange direction, in a straight line, and extend 

from within the food product area to the outer edges of the lid.

3/ Scale or dust on the outside of container caused by retort water may be removed by 

washing.

The following examples shall not be scored as defects for unclean:

a. Water spots.

b. Ten or less specks of dried product each of which measure 1/8 inch by 1/8 inch or 
MIL-PRF-32004C

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equivalent area, or less.

c. Any foreign matter which presents no health hazard or no potential container damage 

and which readily falls off when container is lifted and shaken lightly.

d. Very thin film of grease, oil, or product residue which is discernible to touch, but not 

readily discernible by visual examinations.

e. Thread-like strands or specks of melted and hardened polyolefin, typically along the 

outer edges of the lid and tray flange.

4/ Score this defect only if fingernail “catches” when dragged over wrinkle.

5/ The following shall be scored as minor defects if present within 1/16 inch of the food 

product edge of seal:

a. Small concave impressions or cavities indicating slight tray imperfections or hard 

particulates affixed to the seal head and contacting the lid and tray.

b. Small (e.g., 1/32 inch or less in any direction) convex bumps or points on the seal area 

indicating small imperfections on the seal head. NOTE: This anomaly is typically visible on 

successive trays coming off the heat sealer.

c. Minor impressions or scorching of the top layer of the lid material on the seal area 

indicating soft particulates on the seal head being “burned-off” during sealing. NOTE: This 

anomaly is typically visible on successive trays coming off the heat sealer.

d. Anomalies caused by entrapped moisture or vapor (which typically appear as concave 

spots on the tray flange surface) that result in less than 1/8 inch, but not less than 1/16 inch of 

defect free seal width at the outside edge of these spots.

e. For solid products only, anomalies caused by entrapped matter that result in less than 

1/8 inch but not less than 1/16 inch of defect free seal width at the outside edge of these 

spots. Solid products would include eggs, stuffing, mashed potatoes, rice, lasagnas, bakes, 

and other items possessing minimal or no capability for hydraulic stresses during transport, 

and would exclude items packed in brine, gravy, and/or other low viscosity sauces.

6/ Score this defect once at any point perpendicular to the tray flange along the tray 

perimeter.

7/ A Non-Destructive Static Compression Tester (see 4.3.9.2) may be utilized to verify 

container integrity by quantifying the impact of this container defect, if found during the 

visual examination.
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 4.3 Tests.

 4.3.1 Tray configurations and dimensions. Prior to filling, sealing and processing, tray 

dimensions shall be measured and compared to the requirements of figure 1. The tray shall be 

placed on a flat surface and filled with 96 fluid ounces of water. Any tray dimension 

exceeding the requirements of figure 1 or tray that cannot hold a minimum of 96 fluid ounces 

of water shall be considered a test failure.

 4.3.2 Oxygen gas transmission rate. The O2GTR of the material shall be determined in 

accordance with ASTM D3985 at 73°F and 50 % relative humidity.

 4.3.3 Water vapor transmission rate. The WVTR of the material shall be determined in 

accordance with ASTM F1249 at 104°F and 90 % relative humidity.

 4.3.4 Processing. Testing for processing of the material shall be as follows: Material shall 

be formed into trays in accordance with figure 1. For Type I, trays shall be filled with 

approximately 96 ounces of water, sealed with the tray lid material, and exposed to the same 

processing conditions as required by the food product document. For Type II, trays shall be 

filled and sealed with representative product in accordance with the appropriate food product 

document. Following processing, containers shall be examined in accordance with table II.

 4.3.5 Protective sleeve (Type I, Style A). The protective sleeve with the filled, sealed and 

processed tray inside shall be placed on a flat surface and examined for conformance to 

dimension, labeling, and stacking strength requirements. Any sleeved tray with a height 

greater than 2-1/8 inches; or sleeve not covering the entire flange length; or sleeve exceeding 

12-13/16 inches in length; or sleeve not preventing sliding of the tray along the sleeve width; 

or sleeve not continuously compressed in such a manner as to keep the top sleeve face flush 

against the tray seal surfaces; or sleeve that does not prevent the tray from sliding out through 

an open end; or sleeve not providing added stacking strength equivalent or better than a 

sleeve constructed of grade 275 fiberboard in accordance with ASTM D5118/D5118M and 

with flutes oriented parallel to the sleeve width; or sleeve not of a natural kraft, tan or dull 

gray color; or label instructions missing; or label instructions not legible shall be considered a 

test failure.

 4.3.6 Fiberboard pad (Type I, Style B and Type II). The fiberboard pad shall be examined 

for conformance to dimension requirements. Any fiberboard pad that is not within 1/8 inch of 

the full length and width of the inside dimensions of the box, or is not fabricated of class D, 

burst grade 275 fiberboard or stronger, or is not of a natural kraft, tan or dull gray color shall 

be considered a test failure.

 4.3.7 Rough handling survivability. Container survival rates shall be 100 % at standard 

temperature (see 4.3.7.1) and at least 85 % at frozen temperature (see 4.3.7.2).
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 4.3.7.1 Standard temperature test. Four trays, filled with a representative food product, 

processed and prepared as specified in the applicable food document shall be inserted into the 

protective sleeve as specified in 3.1.6 and packed in a snug fitting fiberboard box conforming 

to style RSC-L, type CF, grade 275 of ASTM D5118/D5118M. The sleeved trays shall be 

placed flat with the first two trays placed with the lids together and the next two trays with 

the lids together. The inside of each box shall be provided with a box liner. The height of the 

box liner shall be equal to the full inside depth of the box (+ 0 inch, - 1/8 inch). The box shall 

be closed in accordance with ASTM D1974/D1974M. Condition the box of four trays in an 

atmosphere uniformly maintained at 72°F ± 2°F for a period of 48 hours. Conduct a drop test 

in accordance with ASTM D5276, Assurance Level I for a series of 10 drops, to include: (1) 

a bottom corner drop at the manufacturer's joint; (2 & 3) edge drops on the shortest and next 

shortest edges radiating from the corner; (4) an edge drop on the longest edge radiating from 

that corner; (5 & 6) flatwise drops on the smallest and opposite smallest faces; (7 & 8) 

flatwise drops on the medium and opposite medium faces; (9 & 10) flatwise drops on the 

longest and opposite longest faces. Immediately after completion of the drop test, conduct a 

vibration test (on the same box of four trays) in accordance with ASTM D999, at 268 RPM 

(4.5 Hz) for a period of one hour. Remove trays from the box and examine visually. Any 

cracked, split or broken tray or lid at any location; width of defect/anomaly free closure seal 

at the food product edge less than 1/16 inches; or tear, hole, or puncture through protective 

sleeve causing a hole in the tray lid; or wet or stained protective sleeve due to one or more 

leaking trays; or any evidence of food product leakage from tray or lid; or absence of 

protective sleeve; or protective sleeve no longer preventing the tray from sliding out through 

an open end shall be considered a test failure.

 4.3.7.2 Frozen temperature test. Prepare the box of four trays as specified in 4.3.7.1, but 

condition in an atmosphere uniformly maintained at -20°F ± 2°F for a period of 48 hours. 

While still in frozen state, conduct drop and vibration tests as specified in 4.3.7.1. Remove 

trays from the box and allow to fully thaw prior to visual examination. Any cracked, split or 

broken tray at any location, except along the outermost flange edges, or lid at any location; or 

width of defect/anomaly free closure at the food product edge less than 1/16 inches; or tear, 

hole, or puncture through protective sleeve causing a hole in the tray lid; or wet or stained 

protective sleeve due to one or more leaking trays; or any evidence of food product leakage 

from tray; or absence of protective sleeve, shall be considered a test failure.

 4.3.8 Headspace testing.

 4.3.8.1 Residual gas (Type I only). The samples for test shall be opened under 75°F ± 5°F 

water and the gases shall be collected by water displacement in a graduated cylinder or other 

calibrated tube. The volume of the gases shall be reported to the nearest 5 cc. Any residual 

gas volume exceeding 250 cc shall be considered a test failure.

 4.3.8.2 Vacuum (Type II only). Eight filled, sealed and processed polymeric trays shall be 

allowed to cool to 75°F + 5°F and held for at least 24 hours. To examine for vacuum, lay a 
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straight edge onto the tray flanges spanning the entire length of the polymeric tray and 

crossing the center point of the lidding. There shall be a visible gap between the straight edge 

and the lidding material along the entire length of lidding below the straight edge. The same 

procedure shall be used across the width of the polymeric tray. The lidding material shall also 

be examined for evidence of tautness. Any lack of visible gap between the straight edge and 

lidding and lack of tautness by the lidding shall be considered a test failure.

 4.3.9 Internal pressure.

 4.3.9.1 Destructive. Internal pressure resistance shall be determined by pressurizing the 

container without protective sleeve while restrained between two rigid plates. There shall be 

a minimum clearance of 1/8 inch between the bottom surface of the top plate and the top 

surface of the tray flange (with attached lid). A four-seal tester (designed to pressurize filled 

container by use of a hypodermic needle through the container wall or lid) shall be used and 

all four seals tested simultaneously. It may also be necessary to restrain the tray body during 

the test within either a wood or metal base, such that excessive deflection of the tray does not 

render a false lid failure. Pressure shall be applied gradually until 20 psig pressure is reached. 

The 20 psig pressure shall be held constant for 30 seconds and then released. The container 

then shall be examined for separation or yield of the heat seals. Any rupture of the container 

(e.g., through tray, lid or closure seal) or evidence of any seal separation greater than 1/16 

inch or minimum closure seal width less than 1/16 inch shall be considered a test failure.

 4.3.9.2 Non-Destructive (Type I only). Internal pressure resistance and container integrity 

shall be determined by using the approved Non-Destructive Static Compression Tester (ND 

Tester) or other test apparatus expressly approved by the Government as specified below. 

Compress the tray in the ND Tester between the two plates. The outer perimeter of the top 

plate shall extend no closer than 1 inch from the inside edge of the tray flange, thus allowing 

the lid stock to bulge up and strain the seal. The bottom plate shall be shaped to match the 

oval indentation on the bottom of the tray. Apply a compression force of 1,400 pounds on the 

tray and hold for 60 seconds. At the end of the ND test, remove the tray from the Tester, reinspect the seal and measure the minimum closure seal width along the entire tray seal. A 

mark shall be placed on the short side of the tray body to indicate that it has been ND tested.

 4.3.9.2.1 Internal pressure resistance. When determining internal pressure resistance in 

accordance with 4.3.9.2, the following criteria shall apply: (a) Any rupture of the container 

(e.g., through tray, lid or closure seal) or evidence of any seal separation greater than 1/16 

inch or evidence of minimum closure seal width less than 1/16 inch shall be considered a test 

failure. The tray tested shall be withheld from the lot. (b) Any tray passing the ND test and 

possessing a minimum closure seal width greater than 1/8 inch may be placed back into the 

lot.

 4.3.9.2.2 Container integrity. When determining container integrity in accordance with 

4.3.9.2, the following criteria shall apply: (a) Any rupture of the container (e.g., through tray, 
MIL-PRF-32004C

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lid or closure seal) or evidence of minimum closure seal width less than 1/16 inch shall be 

considered a test failure. The defect being verified shall be reclassified as a critical defect, for

that lot only, and will result in rejection of the lot. The tested tray shall be withheld from the 

lot. (b) Any evidence of minimum closure seal width greater than 1/16 inch, but less than 1/8 

inch shall not be considered a test failure. The defect being verified shall be reclassified as 

non-scoreable, for that lot only. This may result in the lot passing the visual container 

examination. The tray tested shall be withheld from the lot. (c) Any tray passing the ND test 

and possessing a minimum closure seal width greater than 1/8 inch shall be reclassified as 

non-scoreable, for that lot only. This may result in the lot passing the visual container 

examination. The tray tested may be placed back into the lot.

 4.3.10 Lid opening. Place a filled, sealed and processed tray on a flat surface and remove 

the protective sleeve, if necessary. Position one hand along the tray flange and use a sharppointed knife in the other hand to cut open the lid along the inside edge of the complete tray 

flange, approximately 1/4 inches away from the flange edge. The inability to open the lid in 

the manner described herein shall be considered a test failure.

 4.3.11 Camouflage. Visually examine the exterior surfaces of the tray and tray lid after 

processing. 

 5. PACKAGING

This section is not applicable to this specification.

 6. NOTES

(This section contains information of a general or explanatory nature that may be helpful, but 

is not mandatory.)

 6.1 Acquisition requirements. Acquisition documents should specify the following:

 a. Title, number, and date of the specification.

 b. Type required (see 1.2).

 c. Style required (see 1.2.1).

 d. Sampling for conformance inspection (see 4.1).

 6.2 Tray material. The US Army Research, Development and Engineering Command 

(RDECOM), Natick Soldier Research, Development and Engineering Center (NSRDEC) has 

found that a seven layer coextruded structure consisting of polypropylene, regrind, tie, 

ethylene vinyl alcohol (EVOH), tie, regrind, and polypropylene, when formed into a tray 
MIL-PRF-32004C

15

with a minimal wall thickness of 0.032 inches, a tray weight of 155 grams ± 15 grams, an 

EVOH content of 6 percent, and a minimum EVOH barrier layer thickness of 0.0015 inches 

meets the performance criteria of this specification. A polymeric tray (Drawing #9212, 

Revision H) constructed of the above material is available from Silgan Plastic Food 

Containers, Union, MO 63084. Note: It has been found that during rough handling testing at -

20° F (see 4.3.7.2) the possibility exists that in a small percentage of containers, the tray 

body at the open ends of the protective sleeve may fracture from excessive dropping. Care 

should be taken to minimize the rough handling of polymeric trays when frozen.

 6.3 Lid material. It has been found that a lid material structure consisting of, from inside 

to outside, 0.003 to 0.004 inch thick polyolefin, 0.00035 to 0.0007 inch thick aluminum foil, 

a 0.0006 inch thick biaxially oriented polyamide and 0.0005 inch thick polyester meets the 

performance criteria of this specification. A lid material structure consisting of, from inside 

to outside, 0.003 inch thick polyolefin, 0.0006 inch thick biaxially oriented polyamide, 

0.0008 inch thick aluminum foil and 0.0005 inch thick polyester also meets the performance 

criteria of this specification. A lid material structure consisting of, from inside to outside, 

0.004 inch thick polyolefin, 0.0006 inch thick biaxially oriented polyamide, 0.00035 inch 

thick aluminum foil and 0.0005 inch thick polyester also meets the performance criteria of 

this specification. RDECOM, NSRDEC has found that a lid material structure consisting of, 

from inside to outside, 0.004 inch think polyolefin, 0.00035 inch thick aluminum foil, 0.001 

inch thick biaxially oriented polyamide and 0.0005 inch thick polyester also meets the 

performance criteria of this specification. A lid material structure consisting of, from inside 

to outside, 0.004 inch thick polyolefin, 0.0006 inch thick biaxially oriented polyamide, 

0.0005 inch thick aluminum foil and 0.0005 inch thick polyester also meets the performance 

criteria of this specification. It has also been found that a lid material structure consisting of, 

from inside to outside 0.003 to 0.004 inch thick polyolefin, 0.0006 inch thick biaxially 

oriented polyamide, 0.00035 thick aluminum foil and 0.0005 inch thick polyester meets the 

performance criteria of this specification. A plus or minus 20% tolerance is permitted for thin 

gauge plastic film thickness measurements and a plus or minus 10% tolerance is permitted 

for aluminum foil thickness measurements. Note: RDECOM, NSRDEC has observed that 

during rough handling testing at -20°F (see 4.3.7.2), the possibility exists that the lid material 

may pinhole, puncture, or develop raised bumps from frozen food product within the tray. 

Care should be taken to minimize the rough handling of polymeric trays when frozen.

 6.4 Protective sleeve material. It has been found that a protective sleeve material 

constructed of grade 275 fiberboard in accordance with ASTM D5118/D5118M, oriented 

with flutes parallel to the sleeve width, jointed and hot melt glued along either the vertical 

length or bottom face of the sleeve, and then compressed and securely taped across the open 

ends of the sleeve at their midpoints meets the performance criteria of this specification.

 6.5 Non-Destructive Static Compression Tester. It has been found that a Non-Destructive 

Static Compression Tester developed under the Defense Logistics Agency Combat Ration 
MIL-PRF-32004C

16

Network Program, Short Term Project #2016, meets the performance criteria of this 

specification.

FIGURE 1: Dimensional Requirements for the Polymeric Tray.

 All Dimensions are in Inches.

Tray Body (Side)

11-7/8 MAX

12-13/16 MAX

Tray Body (End)

9-1/2 MAX

10-7/16 MAX
MIL-PRF-32004C

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 6.6 Subject term (key word) listing.

 Combat field feeding

 Operational rations

 6.7 Changes from previous issue. Marginal notations are not used in this revision to 

identify changes with respect to the previous issue due to the extent of the changes. 

Custodians: Preparing activity:

 Army - QM Army - GL

 Navy - MC

 (Project 89GP-2016-003)

Review activities:

 Army – MD

 Navy - SA

 DLA - SS

Civil agency:

 USDA - SCP

 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 the ASSIST Online database at https://assist.dla.mil.