0 

USDA GUIDELINES

FOR THE SANITARY

DESIGN AND FABRICATION OF

DAIRY PROCESSING EQUIPMENT

02/2022
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Contents

1. Purpose ................................................................................................................................. 4

2. Scope .................................................................................................................................... 4

3. References............................................................................................................................ 5

4. Definitions............................................................................................................................ 6

5. Engineering Drawings ........................................................................................................ 10

6. Application of Service ........................................................................................................ 11

7. Equipment Review Introduction ........................................................................................ 13

7.1. Design ................................................................................................................... 13

7.2. Construction Materials and Fabrication ................................................................ 13

7.3. Cleanability ........................................................................................................... 13

8. Equipment Review Procedure ............................................................................................ 13

8.1. Certificate of Acceptance ...................................................................................... 14

9. Materials ............................................................................................................................. 16

9.1. Product Contact Surfaces ...................................................................................... 16

9.2. Non-Product Contact Surfaces .............................................................................. 19

10. Fabrication .......................................................................................................................... 19

10.1. Product Contact Surfaces ...................................................................................... 19

10.2. Permanent Joints ................................................................................................... 20

10.3. Soldering and Brazing ........................................................................................... 20

10.4. Fittings .................................................................................................................. 21

10.5. Non-Permanent Joints ........................................................................................... 22

10.6. Sanitary Tubing ..................................................................................................... 23

10.7. Flexible Tubing ..................................................................................................... 23

10.8. Exposed Threads ................................................................................................... 24

10.9. Knuckle Thread ..................................................................................................... 26

10.10. Enclosed Threads .................................................................................................. 26

10.11. Coil Springs .......................................................................................................... 27

10.12. Radii ...................................................................................................................... 27

10.13. Draining ................................................................................................................ 30

10.14. Cleaning ................................................................................................................ 30

10.15. Inspectability ......................................................................................................... 30

10.16. Mixers and Agitators ............................................................................................. 31

10.17. Seals and Sealing Materials .................................................................................. 31

10.18. Air Under Pressure ................................................................................................ 32
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10.19. Covers, Panels, Doors or Access Ports ................................................................. 32

10.20. Guards and Other Safety Devices ......................................................................... 35

10.21. Spray Devices ....................................................................................................... 35

10.22. Service Piping and Lines ...................................................................................... 35

10.23. Culinary Steam and Piping ................................................................................... 35

10.24. Cylinders ............................................................................................................... 36

10.25. Hoses and Connectors ........................................................................................... 37

10.26. Gaskets, O-rings and Seals ................................................................................... 37

10.27. Perforated Surfaces 1 ............................................................................................ 39

10.28. Shafts 1.................................................................................................................. 39

10.29. Bearings ................................................................................................................ 40

11. Non-product Contact Surfaces ........................................................................................... 40

11.1. Supports ................................................................................................................ 42

11.2. Name and Information Plates................................................................................ 43

12. Special Considerations for Pasteurization Equipment ....................................................... 45

13. Special Considerations for Exposed Product Conveyors ................................................... 45

14. Special Considerations for Packaging Machines ............................................................... 48

14.1. Viscous and Dry Product Vertical and Horizontal Packaging Machines ............. 48

14.1.1. Vertical Fillers ................................................................................................ 49

14.1.2. Horizontal Fillers ............................................................................................ 50

15. Special Considerations for Cheese Brine Systems and Related Equipment ...................... 50

16. Special Considerations for Cheese Molds .......................................................................... 53

16.1. Stainless Steel Molds ............................................................................................ 55

16.2. Plastic Molds ......................................................................................................... 56

16.3. Mold Washing Devices: (Non-Recirculating Type) ............................................. 57

17. Special Considerations for Mechanical Cleaning Systems for Large Equipment or Vessels58

18. Special Considerations for Lactose Equipment .................................................................. 61

19. Validation of Prior Acceptance........................................................................................... 62

20. Resolution of Reports of Noncompliance .......................................................................... 62

21. Equipment Manufacturer Responsibilities ......................................................................... 63

22. Equipment User Responsibilities ....................................................................................... 63

23. Appendix ............................................................................................................................ 64

23.1. Stainless Steel and Equivalent Materials .............................................................. 64

23.2. Electroless Nickel Alloy ....................................................................................... 67

24. Instruction Handbook, Maintenance, and Cleaning ........................................................... 69

24.1. Installation of the Equipment and Associated Equipment .................................... 69

24.2. Instructions for Use ............................................................................................... 69
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24.3. Maintenance .......................................................................................................... 69

24.4. Cleaning ................................................................................................................ 69

24.5. Special Cleaning Instruction ................................................................................. 70

25. History ................................................................................................................................ 71
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1. Purpose

The following criteria, guidelines and principles set forth the sanitary design and 

fabrication features required by United States Department of Agriculture (USDA), Dairy 

Grading Branch (DGB) for the acceptance of equipment intended for use in dairy plants 

surveyed and approved for USDA grading service. The DGB is a user fee supported 

service. Therefore, charges will be made for the review of drawings or equipment and 

for related travel and other expenses.

USDA/AMS/Dairy Programs

National Field Office

650 East Diehl Rd, STE 100 

Naperville, IL 60563 

Phone: 630-810-9999 

USDA/AMS/Dairy Programs

Dairy Grading and Standardization 

Division

Room 2746-South Building 

1400 Independence Avenue, S.W.

Washington, DC 20250-0230 

Phone: 202-720-3171 

Fax: 202-720-264

2. Scope

The DGB utilizes established 3-A SSI Sanitary Standards and Accepted Practices for 

equipment that fall under the scope of a particular standard or practice. In the event that 

a piece of equipment reviewed does not fully comply with the applicable 3-A SSI 

Sanitary Standards or Accepted Practice, however, the equipment does meet the 

minimum requirements of the USDA Dairy Equipment Guidelines, the DGB will 

evaluate the discrepancy. If it can be determined that the equipment in question will not 

contribute to unsanitary conditions and/or public health issues, DGB will still issue a 

letter of acceptance and certificate.

3-A SSI Sanitary Standards and 3-A SSI 

Accepted Practices Websites

www.3-a.org

www.techstreet.com/3Agate.html

The 3-A Sanitary Standards provide criteria for materials and fabrication for specific 

types of dairy equipment. Examples of equipment covered by 3-A Sanitary Standards 

are centrifugal and positive displacement rotary pumps, compression valves, non-coil 

batch processors, and bag collectors for dry milk products. The 3-A SSI Accepted 

Practices establish criteria for the materials, fabrication, and installation of processing 

systems which employ component pieces of equipment, many of which are covered by 

3-A Sanitary Standards. Examples of 3-A Accepted Practices are Spray Drying 

Systems, HTST Pasteurizer Systems, and Culinary Steam Producing Systems. 
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If the applicant would like to receive a USDA DGB Certificate of Acceptance, the 

USDA DGB will still require an inspection of the equipment even if the equipment bears 

the 3-A symbol. Equipment bearing a 3-A symbol will be subjected to routine plant 

survey evaluation for sanitation under the USDA Dairy Plant Survey Program. If the 

routine inspection reveals deficiencies with materials, design, fabrication, or 

workmanship, which appear to violate the USDA Dairy Equipment Guidelines and/or 

applicable 3-A Sanitary Standards, DGB will request the fabricator to make appropriate 

modifications. In the case of noncompliance with the 3-A SSI Sanitary Standard or 

Accepted Practice, a Report of Alleged Non-Compliance (RAN) may be filed with 3-A 

SSI. 

Equipment buyers are encouraged to request USDA-DGB acceptance for equipment as a 

provision of their purchase contract. The requirement should be clearly written so as not 

to confuse USDA-DGB acceptance with compliance with other requirements, such as 

3-A SSI Sanitary Standards or requirements of other Federal or State Agencies. 

Equipment accepted under the USDA Dairy Livestock and Poultry Equipment Review 

program, or approved by the USDA, Food Safety and Inspection Service (FSIS), or State 

inspection agencies does not infer acceptance by the USDA DGB. When a USDA-DGB 

review is requested of equipment for which there are no 3-A Sanitary Standards or 

Accepted Practices, USDA will use the following general criteria, guidelines, and 

principles of this document. Sections 4-10 shall apply unless modified by “Section 12- 

18 Special Considerations”. 

3. References

• “3-A Sanitary Standard for General Requirements ANSI/3-A 00-01 2018” is 

referenced throughout the document including images. 

• 3-A Sanitary Standard for Sifters for Dry Products Number 26-06 

• 3-A® Sanitary Standards for Hose Assemblies, Number 62-02 

• 3-A® Sanitary Standard for Sight and/or Light Windows and Sight Indicators 

• in Contact with Product Number 65-01 

• 3-A® Sanitary Standards for Shear Mixers, Mixers, and Agitators, Number 73-01 

• 3-A Sanitary Standard for Spray Cleaning Devices Intended to Remain in Place, 

Number 78-03 

• 3-A® Sanitary Standards for Personnel Access Ports for Wet Applications, 

Number 84-02 

• 3-A Sanitary Standard for Equipment Feet and Supports, Number 88-01 

• 3-A® Accepted Practices for the Sanitary Construction, Installation, Testing and 

Operation of High-Temperature Short-Time and Higher-Heat Shorter-Time 

Pasteurizer Systems, Number 603-07 

• 3-A® Accepted Practices for Permanently Installed Product and Solution 

Pipelines and Cleaning Systems Used in Milk and Milk Product Processing 

Plants, Number 605-04 

• 3-A® Accepted Practices for A Method of Producing Culinary Steam, Number 

609-03 

• "Machinery's Handbook" published by Industrial Press, Inc., 200 Madison Ave., 

New York, NY 10157. 

• ASTM G31 Laboratory Immersion Corrosion Testing of Metals 

• Title 21 Code of Federal Regulations, Parts 170-199
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• ASTM G31 Laboratory Immersion Corrosion Testing of Metals

• American Welding Society (AWS)/ American National Standards Institute 

(ANSI)-D18.1 

4. Definitions

1. Bond: Adhesive materials or possibly cohesive forces holding components 

together. This definition does not include press and shrink fits. 

2. Brazing: A bonding process between materials by heating them to the brazing 

temperature with a filler metal having a melting point above 840oF (450oC) and 

below the melting point of the base metal. The filler metal flows between the 

closely fitted surfaces of the joint by capillary action.

3. Brazing Filler Metal: The metal or alloy used as a filler metal in the brazing 

process that has melting point above 840oF (450oC) and below the melting point 

of the base metal.

4. Burr: A thin ridge or sharp edge remaining after cutting, drilling, grinding, 

polishing, shearing or punching a material. 

5. CIP-able: The design and fabrication of equipment which allows the equipment 

surfaces to be cleaned by CIP methods for a prescribed time and at a prescribed 

concentration, flow rate, pressure, and temperature demonstrated to be effective.

1

6. Cleaned-in-Place (CIP): The process of removal of soil from product contact 

surfaces in their process position by circulating, spraying, or flowing chemical 

solutions and water rinses onto and over the surfaces to be cleaned.

7. Clean-Out-of-Place: (COP): Removal of product residues and soil from 

equipment when it is removed from its installed position. The equipment or 

assembly may be partially or totally disassembled. Cleaning is accomplished by 

circulating chemical solutions and water rinses in a wash tank. The wash tank 

may be fitted with circulating pump(s).

8. Cleanable or Cleanability: When Materials of construction, design and 

fabrication will ensure that surfaces will allow the removal of product residues 

and soil. 

9. Close Coupled: Mounting or connecting of components so that the intervening 

product contact area separating the components is as short as possible. 1

10. Corrosion Resistant: A surface or material which has the property to retain its 

original surface characteristics through its predicted service period when exposed 

to the conditions encountered in the environment of intended use. This includes 

contact with product, cleaning and sanitizing chemicals, steam, or sterilization 

compounds or solutions. 1

11. Coatings, Overlays and Encapsulations: A process where a different material is 

deposited to create a new product contact surface. There is a buildup of new 
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material. The coating, overlay, or encapsulation material does not alter the 

physical properties of the substrate. 1

12. Dead End or Space: An area in which product, ingredients, cleaning solution, or 

sanitizing solution, or other matter, may become trapped, retained, or not 

completely removed during production or ensuing cleaning procedures. 

13. Dry Cleaning: Cleaning without the aid of liquid using a vacuum cleaner and/or 

dry brushes and other tools manipulated by hand. 

14. Dry Dairy Product: Dry Milk, dry milk product or other dairy product that is 

free of visible moisture or added moisture, free flowing, granular, crumbled, 

diced, shredded, or cubed. 

15. Essential Functional Reason: A condition or feature of the design or 

fabrication of a piece of equipment that cannot be modified and is required for 

the proper operation of the equipment. 1

16. Fillers: 

a. Horizontal Fillers- Fill the container as it moves in a horizontal plane. This 

would include fillers with turntables or forming/filling wheels.

b. Vertical Fillers- Fill the container as it moves in the vertical plane. 

17. Fittings, Clean in Place (CIP): Fittings designed to be cleaned while fully 

assembled. If the fitting has a removable joint, the joint shall be self-centering, 

gasketed, and the gasketed joint forms a substantially flush interior surface. 

18. Fittings Manually Cleaned: Removable joint fittings that are not capable of CIP 

and require disassembly for manual cleaning. (i.e. Bevel Seat Fittings)

19. Inlet: An opening that allows product, solutions, ingredients, steam, or air to 

enter the equipment.

20. Inspectable: Item or area that can be made available or exposed for close visual 

observation. 

21. Manual Cleaning: Cleaning method to remove all soil from product contact 

surfaces while completely or partially disassembled. Soil removal is promoted 

with cleaning solutions and water rinses with the assistance of one or a 

combination of brushes, nonmetallic scouring pads, scrapers, and/or high- or 

low-pressure hoses, with cleaning aids manipulated by hand. When this method 

of cleaning is required, the equipment design shall be easily disassembled. The 

disassembly may be done with or without simple hand tools. 

22. Non-product Contact Surface: All exposed surfaces from which splashed 

product, liquids, or other soil cannot drain, drop, diffuse or be drawn into or onto 

the product, product contact surfaces, open packages, or the product contact 

surfaces of package components. 1
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23. Non-Toxic Materials: Substances, which under the conditions of their use, 

comply with applicable requirements of the applicable FDA Regulation. 

24. Outlet/Product Outlet: An opening that allows product or solutions to exit the 

equipment or vessel.

25. Perforated Screens: Metal sheets, which have punched, cut, drilled or formed 

openings or holes.

26. Permanent Joint: A joint between two components which is unable to be 

disassembled. 1

27. Processing Area: A room or area suitable for the manufacturing and packaging 

of dairy products. 

28. Product: Milk, milk products, including all related dairy products, or fraction 

thereof which is to be produced, processed or packaged by the equipment. 

29. Product Contact Surface: All surfaces which are exposed to the product and 

from which splashed product, liquids, material or soil may drain, drop, diffuse or 

be drawn into the product, interiors of product containers, onto the product 

contact side of packaging materials or onto surfaces that come into contact with 

product contact surfaces of packaging materials.

Note:

The product contact surfaces of exposed product conveyors and packaging 

equipment may be isolated by sanitary shielding or other acceptable means of 

clear demarcation. (See Section 13 & 14)

30. Readily Accessible: A location that can be safely reached by personnel from the 

floor, other permanent work area or stable platform (permanent or moveable.) 1

31. Regulatory Agency: The state or local agency having regulatory jurisdiction, or 

the validation for compliance (testing, timing and sealing) with legal 

pasteurization criteria as set forth in the PMO. 

32. Readily Removable: A design, fabrication, including installation that will allow 

the equipment or appurtenance(s) of the equipment to be quickly separated with 

or without the use of simple hand tools. 

33. Roughness Average (Ra): The arithmetical mean of the absolute values of the 

surface profile departure within a sampling length. (ANSI)/American Society of 

Mechanical Engineers (ASME) B46.1 Surface Texture Waviness and Lay. 

Available from the American Society of Mechanical Engineers, 345 East 47th 

Street, New York, NY 10017-2392, Phone: (212) 705-7722. 

34. Safe Water: Water from a supply properly located, protected, and operated, and 

shall be of a safe, sanitary quality. The water shall meet the standards as 

described in the National Primary Drinking Water Regulation of the 
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Environmental Protection Agency (EPA) (Refer to B4, Reference No. 4) or 

Category I Reclaimed Process Water as described in Appendix D of the PMO. 

35. Sanitizing or Sanitization: A process applied to a clean surface which is 

capable of reducing the numbers of the most resistant human pathogens by at 

least 5 log10 reductions (99.999%) to 7 log10 reductions (99.99999%) by applying 

hot water, hot air, or steam, or by applying an EPA-registered sanitizer according 

to label directions. Sanitizing may be affected by mechanical or manual 

methods. 1

36. Sealed: Closed to the penetration of fluids by the application of one or more 

continuous welds, soldering, brazing, coatings, overlays, encapsulations, 

adhesives, rubber, rubber-like or plastic gasket under compression, mechanical 

force seals or press-fits or shrink-fits. 

37. Shadow Areas: Obstructed areas on product contact surfaces where cleaning 

solutions will not flow or impinge directly across and onto the surfaces to be 

cleaned.

38. Simple Hand Tools: Shall mean implements or utensils normally used by 

operating and cleaning personnel. (i.e. screwdriver, wrench, or mallet.)

39. Splash Contact Surface: Non-product contact surfaces that during normal 

operation or use are subject to accumulations of soil and which require routine 

cleaning.

40. Soil: Unwanted organic residue or inorganic matter. 1

41. Solder: The metal or alloy used as a filler metal in soldering, which has a 

melting point not exceeding 840oF (450oC) and below the melting point of the 

base metal.

42. Soldering: A joining process that produces coalescence of materials by heating 

them to the soldering temperature and using a filler metal having a melting point 

not exceeding 840o

F (450oC) and below the melting point of the base metals. 

The filler metal is distributed between closely fitted surfaces of the joint by 

capillary action by wetting of the surfaces by using soldering flux. 

43. Solution: Water or any mixture of water and cleaning agents, or sanitizers used 

for flushing, cleaning, rinsing, or sanitizing. 

44. Solution Contact Surfaces: All interior surfaces of the equipment or system, 

including associated piping, and tanks that are used for supplying and 

recirculation cleaning and/or sanitizing solutions. This does not include 

equipment or pipelines used to supply concentrated cleaning and sanitizing 

chemicals from bulk storage to the point of chemical addition.

45. Sterilization: A process affected by heat, chemicals, or other mechanical means 

that destroys all vegetative bacteria and inactivates relevant bacterial spores of 

public health concern. 1
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46. Substantially Flush: Mating surfaces or other associated surfaces, such as 

gaskets, butt welds, and fitting alignment, that are not more than (+/-) 1/32 in. 

(.031 in) off-set. 1

47. Surface Coating: Shall mean the results of a process whereby a different 

material is deposited upon a surface to create a new surface with altered 

functional characteristics and there is an appreciable build-up (greater than 1 

micrometer) of new material. Surface coating may include;

• Chemical (conversion coatings except anodizing). 

• Engineering Plating. (e.g., electro-deposition, gold)

• Thermal Spraying (e.g., flame, plasma, arc spraying) 

• Physical Vapor Deposition. 

• Chemical Vapor Deposition. 

• Overlays and Encapsulation. 

48. Surface Treatment: Process whereby chemical compositions or mechanical 

properties of the existing surface are altered and there is no appreciable build-up 

(less than 1 micrometer) of new material. Surface treatments may include;

• Mechanical (grinding, shot peening, glass beading, polishing) 

• Thermal (surface hardening laser, electron beam)

• Diffusion (carbonizing, nitriding)

• Chemical (etching, oxidation, passivation)

49. Viscous Product: Shall mean semi-fluid product which is pumpable or flowable 

at packaging condition. 1

5. Engineering Drawings 

A. Engineering drawings of the entire piece of equipment are generally required for 

evaluation of details for USDA acceptance. Engineering drawings must be of 

sufficient detail to clearly show:

- The dimensions of each part; 

- The minimum radii dimensions of internal angles of less than 135 degrees; 

- The product contact surface finish specifications;

- The specifications for welds and other permanent joints;

- The design details for flanges, or gasketed joints which are to include enlarged 

drawing(s) (at least 2X) of the details of O-ring retaining grooves as appropriate; 

- The dimensions of O-rings, gaskets, and any other type of seals; and 

- Explanations about company welding symbols and metal finishes. 

B. Dimensions may be shown in either English or metric measurement terms. The 

required materials listings and terminology on the drawings should be in English or 

include translations into English. Concept or assembly drawings should also be 

provided as they are useful in showing the general configuration of the equipment 

and the relationship of component parts to each other. If the applicant needs to have 

the equipment reviewed in a shorter time an on-sight visit can be conducted or by 
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drawings sent for review. A request can be made for a meeting to review drawings 

and/or parts for a quicker turnaround time as well. Alternatively, the review can be 

performed on a finished piece of equipment on-site, either at the equipment 

manufacturer or at a processing plant. The requirements for this type of review are: 

- Safe access must be provided. 

- All product contact surfaces must be clean and available for inspection. 

- Food and Drug Administration/Code of Federal Register (CFR) and 3-A Sanitary 

Standards certifications for all rubber and plastic materials should be available.

6. Application of Service

A. To initiate a sanitary design review, the perspective applicant may contact the DGB

by telephone, fax, e-mail, or mail. A request for inspection is to be accompanied by 

an Equipment Review Request form (see below). Applicants are advised that a 

minimum of 40 working days advance notice is required for any foreign travel and a 

minimum of 14 working days advance notice is required for domestic travel. Design 

evaluations and travel to inspection sites is based on a first-come-first-served basis 

and inspector availability. Applicants are encouraged to contact the DGB, National 

Field Office, Lisle, Illinois to verify inspector availability and schedules prior to 

submitting a request for service. If the date(s) requested is not a suitable date the 

DGB will contact the requestor to arrange an agreeable date for all parties.
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U. S. Department of Agriculture Agricultural Marketing Service Dairy Programs 

Equipment Review Request

Applicant (Name and Address) Party Responsible for Payment if 

other than Applicant (Name and 

Address) Confirmation Required 

(Letter or Fax) Received 

Equipment Located at (Name and 

Address) 

Website 

Tax Identification No. (TIN) Tax Identification No. (TIN) Inspection Date(s) Requested: 

Contact Contact Contact 

Telephone Telephone Telephone 

Fax Fax Fax 

Type of Equipment: 

Dairy 

Livestock and Poultry 

3-A Third Party Verification  

Signature of Applicant Date Email 

 Domestic Inspection: A minimum of fourteen (14) working days notification is required to insure specialists 

have ample time to make arrangements for the trip. If specialists are unavailable, the next available date 

acceptable to all parties will be assigned. 

 Foreign Inspection: A minimum of forty (40) working days advance notice is required for any foreign travel. 

The forty-nine days will start from the date this request form Is received by the Dairy Grading Branch. If 

specialists are unavailable, the next available date acceptable to all parties will be assigned. Hotel 

accommodations (USDA Dairy must pay): Best mode of transportation from airport (train, taxi, company 

pickup...): Does the Hotel accept Visa credit cards:  Yes  No 

If submitting electronically, please sign and mail or fax a copy of this form to the address below: Dairy 

Equipment Review , and Livestock and Poultry Equipment Review Address: USDA/AMS/DAIRY 

PROGRAMS, Dairy Grading Branch Design Review Section Room 2746 – South Building, 1400 Independence 

Ave. SW STOP 0230, Washington, DC 20250-0230; Tel: 202 720-3171 Fax: 202 720-2643 

According to the Paperwork Reduction Act of 1995, an agency may not conduct or sponsor, and a person is not required to respond to a 

collection of information unless it displays a valid OMB control number. The valid OMB control number for this information collection is 

0581-0126. The time required to complete this collection of information is estimated to average 3 minutes per person including time for 

reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the 

collection of information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis 

of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all 

prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information 

(Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at 202-720-2600 (voice and TDD). To file a complaint of 

discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, 1400 Independence Avenue, SW, Washington, 

DC 20250-9410 or call 202-720-5964 (voice and TDD). USDA is an equal opportunity provider and employer. 

FOR OFFICIAL USE ONLY 

Date Received: 

Specialist Assigned: 

Date Assigned: 

Project Number (s): 

DA-162 (10-03) Destroy previous edition dated 09-00 

 

 
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7. Equipment Review Introduction

A. The equipment review will encompass three aspects; design, construction materials 

and fabrication as they relate to the equipment’s cleanability. 

7.1. Design 

A. Design review will include both product contact and nonproduct contact surfaces in 

accordance with the criteria outlined in the Foreword section of this publication. 

7.2. Construction Materials and Fabrication

A. Fabrication will be evaluated by the physical inspection of completed units, usually 

at the fabricator’s facilities or at the dairy plant. The equipment will be checked for 

workmanship, metal finish, and adherence to the accepted drawings. 

7.3. Cleanability 

A. Cleanability will be evaluated on a completed unit after a period of actual use. The 

cleanability inspection may require extensive disassembly of component parts to 

fully evaluate design characteristics as they relate to cleanability. Equipment 

cleanability is directly related to the basic design. In general, equipment for manual 

cleaning must be designed so that access to product contact surfaces can be easily 

achieved with the use of simple tools generally available to a dairy plant production 

employee. Equipment intended for CIP (clean-in-place) cleaning must be designed 

so that all product contact surfaces will be subjected to sufficient cleaning solution 

to completely remove all product residue during the cleaning cycle. While bacterial 

swab tests of cleaned surfaces and bacterial tests of finished products are important 

indicators of cleanliness, they will not constitute the sole criteria of design 

suitability. Physical inspection of surfaces will be the primary method for the 

evaluation of cleanability. 

8. Equipment Review Procedure

A. Equipment offered for review should be designated by a specific model number or 

descriptive name for clear identification. Equipment which may be manufactured 

in both sanitary and non-sanitary configurations may bear the same basic model 

number provided that a prefix or suffix is added to clearly differentiate the styles.

B. Equipment submitted for design review during the blueprint stage will be granted a 

preliminary acceptance pending satisfactory demonstration of fabrication 

workmanship and cleanability. Full, unrestricted acceptance will be granted upon 

successful completion of all three aspects of the review process.

C. Acceptance will be further identified according to the mode of cleaning for which 

the unit is designed. The acceptance will be designated as follows:

a. Manual Cleaning- Acceptance when cleaning is accomplished by complete 

disassembly and manual cleaning.
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b. Partial CIP- Acceptance with CIP cleaning of major portions of the unit and 

with the disassembly and manual cleaning of some component parts. 

c. Full CIP- Acceptance with complete CIP cleaning of entire unit.

D. Upon acceptance of a particular unit, the manufacturer accepts the responsibility of 

informing the USDA, DGB, about subsequent design changes and to submit such 

design modifications or improvements for review and acceptance.

8.1. Certificate of Acceptance

A. Upon acceptance of a piece of equipment, the applicant has the option of requesting 

a Certificate of Acceptance (see below). The certificate may be used in sales 

brochures, displays, etc., to show that the piece of equipment has been reviewed and 

accepted by the USDA- DGB. The certificate expires 5 years from the date of issue. 

If during the 5-year period, any changes are made to the design, materials of 

construction, or fabrication of the equipment, all changes shall be submitted to the 

USDA-DGB for review and comment. If the design changes do not affect the status 

of the accepted equipment, the acceptance will continue without interruption. It is 

the applicant’s responsibility to notify the USDA-DGB if they wish to renew their 

certificates after the 5-year period has expired. 
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UNITED STATES DEPARTMENT OF AGRICULTURE

MARKETING AND REGULATORY PROGRAMS

AGRICULTURAL MARKETING SERVICE

EQUIPMENT ACCEPTANCE CERTIFICATE 

Firm: 

Model Designation:

 Date of Issuance U.S. Department of Agriculture

Marketing and Regulatory Programs

Agricultural Marketing Services

Dairy Grading Branch

1400 Independence Ave., SW

Washington, DC 20250-0230

Date of Expiration

The issuance of this form is based on U.S. Department of Agriculture, Dairy 

Grading Branch, Equipment Design Review Section, evaluation of the 

equipment listed above for compliance with:

This form does not limit USDA’s responsibility to take appropriate action in cases in 

which evidence of non-compliance, improper maintenance, or non-sanitary 

conditions have been observed.

United States Department of Agriculture

DA-161 (09-04) Destroy previous editions. 
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9. Materials 

9.1. Product Contact Surfaces

A. All materials having product contact surfaces shall be of such composition as to 

retain their surface and conformational characteristics when exposed to the 

conditions encountered in the environment of intended use including cleaning and 

sanitization treatment or sterilization. 1

B. Stainless Steel: Shall be of the Association for Iron and Steel Technology (AIST) 

300 series or corresponding Alloy Cast Institute (ACI )types or stainless steel that is 

non-toxic and non-absorbent and which under conditions of intended use is equal in 

corrosion resistance to stainless steel of the AIST 300 series (excluding types 301 

and 302) or corresponding ACI types, except that: 

a. AIST 302, 303 and 400 series may be used for springs, cutting blades, and 

when heat treating is required. These grades of stainless steel shall have 

adequate corrosion resistant properties for the conditions of use. 

b. The data for AIST 300 series are contained in the AISI Steel Products 

Manual, Stainless & Heat Resisting Steels, Table 2-1. American Iron and 

Steel Society, 410 Commonwealth Drive, Warrendale, PA 15086, Phone: 

(412) 776-1535. 

c. The data for ACI types are contained in the Steel Casting Handbook, 

Supplement 2, Steel Founders Society of America, 780 Mc Ardle Dr., Unit G, 

Crystal Lake, IL 60014, Phone: (815) 455-8240, Fax: (815) 455-8241, 

Internet: www.sfsa.org

C. Solder: Shall be gold, nickel/chrome or silver-containing metals (sometimes referred 

to as silver solder); shall be corrosion-resistant, free of cadmium, lead and antimony, 

and shall not impart any toxic substance to the product under normal use and when 

exposed to the conditions encountered in the environment of its intended use. This 

includes cleaning, sanitizing treatment, and/or sterilization.

D. Metal Alloys: Are metals other than noted in “Stainless Steel” (see above) shall be 

as corrosion resistant as 300 Series Stainless Steel. This may be shown when metal 

alloys or metals are tested in accordance with ASTM G31 Laboratory Immersion 

Corrosion Testing of Metals and have a corrosion rate of less than 10.0 mil per year. 

The test parameters, including the type of chemical(s), their concentration(s), and 

temperature(s), should be representative of cleaning and sanitizing conditions used 

in the equipment. Alloys containing lead, leachable copper or other toxic metals are 

not to be used. (See Appendix)

E. Plastic Materials: Shall comply with one of the following: 1

a. A regulation listed in Title 21 Code of Federal Regulations, Parts 170-199. 

b. A prior sanction letter, unless previously rescinded. 

c. Meets the criteria for Generally Recognized As Safe (GRAS) status 

(including but not limited to a GRAS regulation or GRAS notice).
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d. A valid Threshold of Regulation (TOR) exemption request. 

e. Is the subject of an effective Food Contact Surface (FCS) Food Contact 

Notification (FCN)? Section 409(h)(2)(C) of the Federal Food, Drug, and 

Cosmetic Act (the Act) states that an FCN is effective for the manufacturer, 

the Food Contact Substance (FCS), and the conditions of use identified in the 

notification only.

f. Determination that migration has not been made and is supported by a 

current Letter of No Objection (or Opinion Letter), issued by the United 

States Food and Drug Administration (USFDA). 

F. Rubber and Rubber Like Materials (Flexible, soft-type): Shall comply with one 

of the following: 1

a. A regulation listed in Title 21 Code of Federal Regulations, Parts 170-199. 

b. A prior sanction letter, unless previously rescinded. 

c. Meets the criteria for Generally Recognized as Safe (GRAS) status 

(including but not limited to a GRAS regulation or GRAS notice).

d. A valid Threshold of Regulation (TOR) exemption request. 

e. Is the subject of an effective Food Contact Surface (FCS) Food Contact 

Notification (FCN)? Section 409(h)(2)(C) of the Federal Food, Drug, and 

Cosmetic Act (the Act) states that an FCN is effective for the manufacturer, 

the Food Contact Substance (FCS), and the conditions of use identified in the 

notification only.

f. Determination that migration has not been made and is supported by a 

current Letter of No Objection (or Opinion Letter), issued by the USFDA. 

g. except that:

h. RTV (Room Temperature Vulcanization) silicone material shall not be used 

in lieu of a gasket in a product contact area 

Note:

When plastic, rubber or rubber like materials are used as product 

contact surfaces, certification that the materials comply with the 

requirements of materials items 9.1.E and 9.1.F shall be provided 

to USDA. All certifications shall include the following information:

• Documentation shall be on company letterhead. 

• Material trade name or type shall be noted. 

• Declaration of compliance with the appropriate Food and 

Drug Administration The corresponding CFR shall be 

cited: (i.e. 21 CFR 177.2600 or 21 CFR 177.1580) 

• Signature of a responsible certifying official.

G. Adhesives: Shall be non-toxic and comply with the applicable Food and Drug 

Administration regulations (21 CFR Part 175). 

H. Carbon, Ceramics, Silicon Carbide, or Tungsten Carbide: Shall be inert, 

non-porous, non-toxic, non-absorbent, insoluble, and resistant to scratching, scoring, 

and distortion when exposed to the conditions encountered in the environment of 

intended use and in cleaning and bactericidal treatment. 
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I. Silver Bearing Solder or Brazing Material: Shall be corrosion-resistant; free of 

cadmium, lead and antimony; non-absorbent; and shall not impart any toxic 

substance to the product when exposed to the conditions encountered in the 

environment of intended use and in cleaning and bactericidal treatment or 

sterilization.

J. Materials Used for Surface Treatments and Coatings: All materials and 

components used for surface treatments and coatings and residues remaining on 

product contact surfaces shall be documented to show they comply with the 

appropriate provisions of the following: 

a. FDA regulations 21 CFR 175, Subpart C - Substances for Use as Components of 

Coatings, or 

b. FDA regulations 21 CFR 177, Subpart B - Substances for Use as Basic 

Components of Single and Repeated Use Food Contact Surfaces, or 

c. FDA regulations 21 CFR 177, Subpart C - Substances for Use Only as 

Components of Articles Intended for Repeated Use, or 

d. Nickel:

1.QQ-N-290a- Federal Specification for Nickel Plating Electrodeposited) 

November 12, 1971. Both documents available from the General 

Services Administration, 18th & F Sts., NW, WFCIA, Washington, DC 

20405 (202-472-2205), or

2.MIL-C-26074E Military Specification: Coatings, Electroless Nickel 

Requirements For. Standardization, Document Automation & 

Production Service (Department of Navy), 700 Robbins Avenue, 

Building 4, Section D, Philadelphia, PA 19111-5094, Phone: (215) 

697-2179, Fax: (215) 697-1462. 

3.(See Appendix 2.) 

e. Rubber and Rubber-Like materials:

1.Shall comply with the provisions of Section 9.1.E of these guidelines.

f. Plastic materials:

1.Shall comply with the provisions of Section 9.1.F of these guidelines.

K. Glass: Shall be restricted to specific uses and shall be of a clear, heat resistant, 

shatter-resistant type.

L. Woven Cotton, Linen, Silk, or Man-made Fibers: Shall be used only for dry 

products flexible connectors and for certain sifting, filtering and screening 

applications.

M. Caulking Materials, including silicone, silastic, or stainless-steel epoxy types: 

May be used to seal pockets or crevices on exterior, non-product contact surfaces.

a. These materials are not acceptable for use on product contact surfaces, except 

as permitted by the 3-A 26- Sanitary Standard for Sifters for Dry Milk and Dry 

Milk Products and as an adhesive for bonded gaskets. 
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N. Paint: Shall be limited to the coating of non-product contact surfaces. Parts 

removable for cleaning having both product contact and nonproduct contact surfaces 

shall not be painted. 

 

O. Lubricants: As provided by FDA regulations, lubricants which have incidental 

food contact shall be limited to those specified in 21 CFR Part 178.3570. The 

amount used shall be the minimum required for the desired technical effect on the 

equipment and shall not exceed any prescribed limitations. Example: Light coating 

of mineral oil on chill rolls to prevent sticking of process cheese.

P. Other Materials: Other materials having certain inherent functional properties 

which are required for specific applications shall be submitted for review and 

evaluation for each application. 

9.2. Non-Product Contact Surfaces

A. All nonproduct contact surfaces shall be of corrosion-resistant material or material 

that is rendered corrosion resistant. If the surfaces are coated, including painted 

surfaces, the coating shall adhere. All nonproduct contact surfaces shall be relatively 

nonabsorbent, durable, and cleanable. Parts that are removable for cleaning having 

both product contact and nonproduct contact surfaces shall not be painted. 1

10. Fabrication 

10.1. Product Contact Surfaces

A. Surfaces, including fabricated, welded, soldered and brazed joints, shall be at least 

as smooth as a 32 μin. (0.8 μm) Ra finish and shall be free of pits, folds, crevices, 

and cracks in the final fabricated form, except that;

a. The 2B mill finish on stainless steel sheets is also considered as smooth as or 

smoother than a polished number 4 finish. No further finishing is required if 

the 2B finish is free of defects, such as pits, scratches, chips, or flakes, in the 

final fabricated form. (Use of adhesive protective paper is recommended 

during equipment fabrication to prevent or minimize damage to stainless 

steel finishes.)

Note:

The 2B finish on stainless steel plate (>3mm) and bars are usually not as 

smooth as the 32 μin. (0.8 μm) Ra finish on sheets due to less cold 

rolling and therefore unacceptable for product contact surfaces without 

additional surface preparation.

B. Electropolishing is an acceptable surface treatment provided the surface has been 

properly prepared to a surface finish that is at least a 32 μin. (0.8 μm) Ra before the 

process is applied. Electropolishing will not remove surface irregularities such as 

pits, folds, or crevices.
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C. The minimum thickness of electrodeposited coatings on product contact surfaces 

shall be not less than 0.0002 inches (0.005mm). 

D. Ceramic materials used as coatings for product contact surfaces shall be at least 

0.003 inch (0.08mm) thick and shall not crack, craze, chip, or spall. 

E. Mechanical surface treatment by shot peening or glass beading of product contact 

surfaces is acceptable provided the treatment serves a specific functional purpose, 

i.e., in order to provide product release on butter and cheese equipment to a 

maximum 125 μin Ra (3.18 μm) The use of this surface treatment will be evaluated 

on a case by case basis. The surfaces shall be prepared to a surface finish that is at 

least a 32 μin Ra (0.8 μm) before the process is applied.

F. Cast metal coatings used as product contact surfaces shall be at least 0.040 inch 

(1.0mm) thick. 

G. Carbon, ceramic, and plastic materials shall be as at least as smooth as a 63 μin Ra 

(1.6 μm Ra) finish and shall be free of chips, pits, cracks, feathering, gouges and 

tooling marks in the final fabricated form. Except that:

a. Machined plastic materials may have a surface finish that is at least as

smooth as a 125 μin Ra. (3.18 μm Ra)

 

H. Surfaces in contact with gaskets, seals, or O-rings in product contact shall be at 

least as smooth as a 32 μin Ra (0.8 μm Ra) finish.

10.2. Permanent Joints

A. Permanent joints shall be continuously welded, ground, and polished to a 32 μin. 

(0.8 μm) Ra finish which is free of pits, folds, crevices or projections except that: 

a. Welds in aluminum product contact surfaces shall be free of pits, folds and 

crevices using the Gas Metal-Arc Welding process with backing bar, and the 

combination of Gas Metal Arc Welding (GMAW) and Gas Tungsten Arc 

Welding (GTAW), or equivalent. 

b. The surfaces shall be slightly finished with a stainless-steel wire brush, resulting 

in maximum weld surface irregularity of twelve thousandth of an inch (0.03mm) 

differential within 1/8 in. (3mm) increments. The maximum weld height shall be 

1/8 in. (3mm). 

B. Properly constructed gasketed junctures. Flanged junctures shall be mated accurately 

and be constructed so the internal sealing edges of the flanges form a sharp 270-

degree angle to create a tight pinch seal with the gasket. Interior surfaces shall be 

substantially flush, with no recessed or protruding unsupported gasket material. 

10.3. Soldering and Brazing

A. Solder and Brazing with accepted materials may be used provide crevice free joints.
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10.4. Fittings

A. CIP Fittings are designed to be cleaned while fully assembled. If the fitting has a 

removable joint, the joint shall be self-centering, employ a gasket, and the resulting 

gasketed joint forms a substantially flush interior surface. Manually Cleaned Fittings 

are removable joints at are designed to be disassembled for manual cleaning. 

Manually cleaned fittings may or may not have a gasket. 

B. Interference Fits or Expansion Fits:

a. Interference fits or expansion fits may be used to produce crevice free permanent 

joints in metallic product contact surfaces when neither welding nor soldering is 

practical. Joints of these types may only be used to assemble parts having 

circular cross sections free of shoulders or relieved areas. For example: They 

may be used to assemble round pins or round bushings into round holes. In both 

types of fit, the outside diameter of the part being inserted is greater than the 

inside diameter of the hole.

b. In the case of the interference fit, the parts are forced together by applying 

pressure. The pressure required is dependent upon the diameter of the parts, the 

amount of interference and the distance the inner part is forced into the outer 

part.

c. In the case of an expansion fit, the diameter of the inner part is reduced by 

chilling to a low temperature. Dry ice is commonly used to shrink the inner part. 

Alternatively, shrink fits are made by heating the outer part. Less assembly force 

is required for this type of fit. (See the following illustrations of acceptable force 

fits and expansion fits.) 

Examples: 1
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d. The design of interference or expansion fit depends on a variety of factors. The 

designer should follow recommended practices to assure that a crevice free joint 

is produced. A recognized authoritative reference is "Machinery's Handbook" 

published by Industrial Press, Inc., 200 Madison Ave., New York, NY 10157. 

e. If interference fit or expansion fit procedures are to be used for metal to plastic 

or plastic to plastic joints, supporting documentation shall be available to 

demonstrate the joints suitability. The tightness of the interference fit or shrinkfit seal shall be validated to demonstrate that there is no migration past the seal 

under the intended conditions of use. 

f. Rubber and rubber-like materials, plastic materials, and carbon or ceramic seal 

may be bonded. The bond shall be continuous and mechanically sound. The 

materials shall not separate from the base materials to which it is bonded when 

exposed to the conditions encountered in the environment of their intended used, 

including cleaning and sanitizing treatment, and/or sterilization. 1

10.5. Non-Permanent Joints 

A. Nonpermanent junctures which are intended for disassembly and manual cleaning 

shall be appropriately gasketed, when necessary. Non-gasketed junctures are 

acceptable in certain applications which will be evaluated on a case by case basis. 

The junctures shall be constructed so they are easily removable with or without the 

use of simple hand tools. Wing, "T", or palm nut style fasteners are preferred over 

hex or dome nuts for non-product fastening applications in order to facilitate 

dismantling for cleaning or inspection.

a. Exceptions may be made, on a case by case basis, for instances when 

conventional bolting may be required for safety, pressure or vacuum 

conditions 

B. Gasketed joints may be used for sanitary fittings and equipment components. The 

interior of the gasket groove shall be designed so the groove is inspectable and 

cleanable when the gasket is removed. 1
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C. Flat gasketed joints that are intended for CIP shall form a substantially flush interior 

surface. Gasketed joints shall be no deeper than their thickness with "T" no less than 

1/32 in. (0.794 mm). 1

Substantially Flush (SF) = 1/32" (0.794 mm) maximum. 1

10.6. Sanitary Tubing

A. Sanitary tubing used to convey product shall be made of stainless steel and where 

welded, may have an “as-welded” interior surface finish that shall be free of pits, 

folds, crevices, cracks, and misalignments as per AWS/ANSI D18.1. (Refer to B1, 

Reference 5.) The weld discoloration in the as-welded condition shall be either weld 

1, 2, or 3. Product piping and other tubular components shall be installed with good 

workmanship and supported in such a manner that will prevent sagging. Product 

piping shall be installed with sufficient slope for drainage.

10.7. Flexible Tubing

A. Sanitary tubing made of flexible rubber or plastic may be used for the following 

applications:

a. Loading or unloading of movable tanks, vessels, or trucks. 

b. Temporary hookups while equipment or permanent piping is being installed. 

c. The prevention of vibration transmission. 

d. Applications where it is important to see the product flow. 

e. Short jumpers for connecting equipment to CIP circuits. 

f. Permeate handling on some membrane systems.

g. Short jumpers required in conveying product for mechanically moving 

parts. 

B. When flexible tubing is slipped over a pipe stub and fastened with a clamp, the 

clamp shall be easily removable, and the hoses stubs shall be removed for daily 

manual cleaning. Screwdriver applied worm screw type clamps (radiator hose 

clamps) are unacceptable. An alternative is to have a flexible hose assembly that 

complies with the applicable 3-A Sanitary Standard 62-, 3-A® Sanitary Standards for 

Hose Assemblies. 
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10.8. Exposed Threads

A. Use of threads is not recommended. Threads should not be used when other means 

of attachment is available. When no acceptable alternative is available, and/or 

threads are required for essential functional reasons, the following criteria shall 

apply: 

a. The threads shall conform to the dimensions of the coarse "Acme" thread, the 

"Brass Valve Stem Thread", or other similar coarse thread design accepted 

by the DGB. 

b. Where exposed threads are necessary for attaching components, the threads

shall be of sanitary design conforming to one of the following illustrations: 

 The American Standard Stub Acme Conforming to the Drawing: 

(The thread angles shall be not less than 60 degrees and with not more than 8 threads to 

the inch (25.4mm), and not less than 5/8 in. (15.9 mm) major basic diameter.) 

P = PITCH P = 1/T.P.I.

S.D. = SINGLE DEPTH S.D = 0.433 x P 

T.F. = TOP FLAT T.F. = 0.250 x P 

B.F. = BOTTOM FLAT B.F. = 0.227 x P 

T.P.I. = THREADS PER 

INCH

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ACME Thread conforming to the following drawing:

 Trapezoid Thread

EXTERNAL THREAD DIMENSIONS

Siz

e 

Acm

e 

Thre

ads

per 

in.

P Q Pitc

h 

Dia.

Tolera

nce

P,Q & 

P.D.

1 8 1.3

17 

1.4

62 

1.39

95 

+.000 / 

-.018 

1 

1/2 

8 1.8

49 

1.9

94 

1.93

15 

+.000 / 

-.019 

2 8 2.3

81 

2.5

26 

2.46

35 

+.000 / 

-.020 

2 1⁄2 8 2.9

13 

3.0

58 

2.99

55 

+.000 / 

-.021 

3 8 3.4

45 

3.5

90 

3.52

75 

+.000 / 

-.022 

4 6 4.5

09 

4.6

95 

4.61

20 

+.000 / 

-.025 

INTERNAL THREAD DIMENSIONS

Si

ze

Acm

e 

Thr

eads 

per 

in.

P Q Pitc

h 

Dia.

Toleran

ce

P,Q & 

P.D.

1 8 1.3

52 

1.4

97 

1.41

45 

+.018 / -

.000 

1 

1/

2 

8 1.8

84 

2.0

29 

1.94

65 

+.019 / -

.000 

2 8 2.4

16 

2.5

61 

2.47

85 

+.020 / -

.000 

2 

1/

2 

8 2.9

48 

3.0

93 

3.01

05 

+.021 / -

.000 

3 8 3.4

80 

3.6

25 

3.54

25 

+.022 / -

.000 

4 6 4.5

44 

4.7

30 

4.62

70 

+.025 / -

.000 
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10.9. Knuckle Thread 

A. The length of a nut, if used on any of threads described in the examples 1, 2, 3, and 

4, shall not exceed 3/4 of the basic thread diameter. The nut shall be of the open 

type. Equipment components with exposed threads as described previously shall be 

designed for disassembly and manual or COP cleaning. 

10.10. Enclosed Threads

A. Where enclosed threads are necessary, the enclosed threads shall conform to all of 

the following:

a) The enclosed threads shall be sealed from the product contact surfaces by 

means of an O-ring, gasket or similar type seal.

b) The assembly using enclosed threads shall be designed for CIP cleaning. 

c) The seal shall have a controlled compression by means of a positive stop to 

prevent overtightening and/or extrusion of the seal. 

d) The tightness of the seal shall be validated to demonstrate that there is no 

migration past the seal under the intended conditions of use. 

e) Enclosed threads shall be cleanable and drainable. 

B. Allen-head and slot-head style bolts or screws are not acceptable on product contact 

surfaces. If a bolted construction is necessary in a product contact area, the bolt 

shall be of hex-head design and properly sealed as noted in 10.10.A. Use of bolted 

construction should be avoided if possible.

C. Welded or sealed threaded studs are preferred fabrication over threaded blind holes. 
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10.11. Coil Springs

A. Coil springs having product contact surfaces shall have openings between the coils 

of at least 3/32 inch (2mm) including the ends, when the spring is in a relaxed 

condition. 

B. Coil springs shall not have the end coils ground flat if they are to clean by CIP. Coil 

springs with the end coils ground flat shall be disassembled for manual cleaning. 

C. Coil springs shall be made of round cross-section stock.

D. When used, modified coil ends terminating with ears or tabs, shall not be modified to 

produce square or rectangular shaped ears or tabs.

E. Coil springs under compression conditions of intended use shall not eliminate all 

spacing between the coils. There shall be a minimum of 1/32 in (0.794 mm). Space 

between each coil when under compression or the spring shall be designed for COP 

or manual cleaning. 

F. A spring may have point contact at the end coils and at intermediate coils with 

retainer rings, and axial contact with rotating shafts, as required for torque 

transmission and maintaining spring alignment. 1

G. All applications and assemblies using coil springs shall be designed, fabricated, and 

installed to make product contact surfaces available for close visual observation 

when either in an installed position or when removed. 

H. Springs less than 1 in. (25.4 mm) outside diameter may have spacing between coils 

of less than 3/32 in. (2.38 mm) When the spring is in the relaxed condition and, 

when under compression, some spacing shall remain between the coils. Such springs 

shall be intended for COP or manual cleaning. 1

10.12. Radii

A. The radii where the head(s) and the side wall(s) of a tank or vessel join shall be a 

minimum of 3/4 in. (19.0 mm).

B. All internal angles of less than 135 degrees on product contact surfaces shall have at 

least a 1/4-inch (6.35 mm) radius. Except that: 

a. Fillets of welds where one or both of the pieces being joined are 3/16 of an inch 

(5mm) thick or less, or in the case of round bar stock, the diameter of one or both 

parts joined is 3/8 in. (9.52 mm) or less, the minimum radii of the welds shall be 

at least 1/8 in. (3.18 mm). 

b. Smaller radii may be used for functional reasons. In this case, the radius shall 

not be less than 1/32 inch (0.794 mm). When radii less than 1/32 inch (0.794 

mm) are needed, they shall be approved on a case-by-case basis provided the 

product contact surfaces are readily accessible and inspectable.
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c. Smaller radii may be used when larger radii will have an adverse effect on the 

dairy product. For example, curd cutting knives or cheese hoops. When radii 

less than 1/32 inch (0.794 mm) are needed, they shall be approved on a case-bycase basis and the product contact surfaces shall be readily accessible and 

inspectable.

d. Internal angles of grooves in gaskets, gasket grooves, or gasket retaining grooves 

shall be not less than 1/32 inch (0.794 mm) except for standard 1/4 inch (6.35 

mm) cross section and smaller O-ring grooves. See item e below. 

e. The internal angles of retaining grooves for standard O-rings shall have 

minimum radii per the following table:

C. Radii in gasket retaining grooves and seats for seals with a nonstandard circular, 

square, rectangular, or other shaped cross section O-ring with the shorter dimension 

1/4 in. (6.35 mm) and smaller shall be those radii closest to the standard circular 

cross section O-ring as specified in the table above. To determine minimum radius in 

the retaining groove for a nonstandard O-ring, compare its cross-section dimension 

with those shown in column 2 of the Table above, determine which is closest, and 

use the applicable minimum groove radius. For a square O-ring, use the flat-to-flat 

side dimension for comparison. For a rectangular or other shaped O-ring, use the 

dimension that will fit into the retaining groove. 

D. There are no minimum radii requirements for:

a. Soldered and brazed joints or for the product contact junctures of press or shrink 

fits.

b. The product contact junctures of flat sealing surfaces. (See illustration)

O-Ring

Cross

Section, 

Nominal 

O-Ring

Cross

Section, Actual 

(AS 568) 

O-Ring

Cross

Section, Actual 

(ISO 3601-1)

Minimum 

Groove Radius 

1/16 in. 0.070 in. 1.80 mm 0.016 in.

(0.406.35)

3/32 in. 0.103 in. 2.65 mm 

 

0.031 in.

(0.787 mm)

1/8 in. 0.139 in. 5.55 mm 0.031 in.

(0.787 mm)

3/16 in. 0.210 in. 5.30 mm

0.062 in.

(1.575 mm)

1/4 in. 0.275 in. 7.00 mm 0.094 in.

(2.39 mm)
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Flat Sealing Surfaces 1

c. Exposed sanitary threads except for the knuckle thread, DIN 405, provided for 

by Section 10.9.A.

d. Gasket retaining grooves for bonded gaskets. Width, depth, and radii are at the 

discretion of the fabricator.

e. For retaining grooves for mechanical force seals or for the juncture between 

product contact surfaces and the exposed part of an O-ring. 

E. In the case of a machined component when a radius in a 90° corner is replaced with 

a pair of 135° angles, the distance between the corners (the hypotenuse of the 

resulting isosceles right triangle) shall be no less than 1/32 in. (0.794 mm) inch for 

the dimension “H” in the illustration E43. 

Illustration E43 1

F. Internal angles less than 135 degrees created by machining or forming of the 

material shall have at least a 1/4-inch (6.35 mm) radius unless required for essential 

functional reasons. In no case shall such radius be less than 1/32 inch (0.794 mm). 

 Product Side

 Non-Product Non-Product
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G. There is no sanitary reason for a minimum radius on external angles which are in 

product contact. Nevertheless, it is customary to relieve sharp edges slightly for 

safety reasons. Care must be taken so that any such relieved edges do not create 

cracks or crevices upon assembly of component parts such as flanged joints. 

 

10.13. Draining

A. All product contact surfaces shall be self-draining except for normal adherence. 

When for essential functional or safety reasons self-draining is not possible, the 

equipment shall be drainable. 

B. Equipment bottoms shall be constructed so they will not sag, buckle, or prevent 

complete drainage. The bottom slope of equipment which is 6 feet (1829mm) in 

diameter or lineal distance from a drainage outlet or less shall be at least 1/4 inch 

(6.35 mm) per foot (305mm). The bottom slope of equipment which is greater than 6 

feet (1829mm) in diameter or lineal distance from a drainage outlet shall be at least 

1/2 inch (13mm) per foot (305mm).

10.14. Cleaning

A. When mechanical cleaning is intended as the only means for cleaning, the equipment 

design shall assure that all product contact surfaces will be free of cracks, crevices 

and dead-end areas that would impede cleaning. Also, the prescribed mechanical 

cleaning procedure shall be proven to effectively clean the equipment.

B. If mechanical cleaning is intended to clean only portions of the equipment, the 

operator's manual shall clearly identify those components which require disassembly 

and manual cleaning.

C. All product and cleaning solution pipelines, sanitary pipe fittings, valves, instrument 

fittings, appurtenances, and components which are part of the equipment shall 

comply with applicable 3-A Sanitary Standards or 3-A Accepted Practices as 

appropriate. 

D. Equipment intended for COP or manual cleaning shall be designed and fabricated so 

all product contact surfaces are readily accessible and inspectable either when in an

installed position or when removed. Junctures between components may or may not 

be gasketed or sealed. All demountable appurtenances shall be readily removable. 1

E. Equipment intended for CIP cleaning shall be designed and fabricated so all product 

contact surfaces including all non-removed appurtenances can be CIP cleaned. 

Junctures between components shall be sealed or designed to be readily removable 

for manual or COP cleaning. 1

10.15. Inspectability

A. When parts having product contact surfaces are too large or heavy for manual 

handling, appropriate mechanical means for handling shall be provided by the 

fabricator or user. 1
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B. All surfaces to be CIP cleaned including all non-removed appurtenances, shall be 

readily accessible and inspectable. All demountable components shall be readily 

removable. 1

C. When cleanability by CIP has been documented and accepted, the design shall 

provide representative surfaces that are readily accessible, and inspectable. 1

10.16. Mixers and Agitators

A. Refer to the 3-A Sanitary Standard 73- (3-A® Sanitary Standards for Shear Mixers, 

Mixers, and Agitators) Except that:

a) When the agitator shaft has an internal bearing cavity, the diameter of the cavity 

(Dimension A) shall be greater than its depth (Dimension B) See the crosssection illustration E59 

 Illustration E59

10.17. Seals and Sealing Materials

A. Rotating shafts shall not have lubricated bearings, including factory sealed bearings, 

in the product contact areas. Such lubricated bearings shall be mounted to provide a 

minimum of 1 inch (25mm) exterior open space on the shaft between the mechanical 

seal for the bearing and the nearest part of the sanitary seal or the opening to the 

product contact area. The 1 inch (25mm) minimum space shall be open to the 

atmosphere and be easily accessible for inspection and cleaning.

B. Where for specialized functional or safety reasons, bearing assemblies must be 

positioned within or in close proximity to the product contact areas, the bearings 

shall be the permanent factory sealed, non-greaseable type. Alternative designs will 

be considered. The alternative design shall provide for;

a. Means to completely isolate the bearing assemblies and provide for the 

collection of all lubricants in the event of a catastrophic bearing or seal 

failure, or
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b. Lubricant impregnated (plastic bushing) bearing materials which have been 

reviewed and accepted by the DGB. 

C. Alternative designs shall be considered on a case-by-case basis. The use of food 

grade lubricant is not considered as an alternative to the above criteria for lubricated 

bearings. 

D. Seal assemblies for rotary shafts for liquid applications shall be of the packless type, 

of sanitary design, durable for the application, and readily demountable. Stacked or 

nested "V" ring seals are NOT considered as packing. 

E. Seal assemblies for rotary shafts for dry products applications shall be of sanitary 

design, durable for the application, and readily demountable. Shaft seal designs 

using adjustable followers are acceptable if provisions are made for easy 

dismantling. Air purge type seal designs may also be acceptable.

F. Woven or braided packing material may be used only for dry product applications. 

This type of packing material shall be discarded when the unit is disassembled for 

wet cleaning. Reuse of woven or braided packing material is prohibited. 

10.18. Air Under Pressure

A. Air under pressure to be introduced directly into product, onto a product contact 

surface or into a product contact surface of a container shall be produced in 

accordance with the "3-A Accepted Practice 604-. “Supplying Air Under Pressure in 

Contact with Milk, Milk Products and Product Contact Surfaces". 

10.19. Covers, Panels, Doors or Access Ports

A. Covers, panels, doors, or access ports shall be provided to allow access to the 

interior of the equipment.

B. Covers, panels, doors, or access ports shall provide protection against the entrance of 

contaminants. 

C. Sight or light openings shall comply with the 3-A Sanitary Standard 65-. “Sight 

and/or Light Windows and Sight Indicators in Contact with Milk and Milk 

Products”.

D. Personnel entry openings for dry applications shall be not less than 15 inches 

(381mm) by 20 inches (508mm) for oval openings or 18 inches (457mm) in 

diameter for round openings. 

E. Personnel entry openings for wet applications shall comply with the applicable 3-A 

Sanitary Standard 84-. (Personnel Access Ports for Wet Applications.)

F. Covers, panels, doors, or access ports into equipment are not limited to round or oval 

shapes. Regardless of shape, the opening cover must protect the product, be easily 

cleanable and meet the criteria of section 10.19. 
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G. Covers, panels, doors, or access ports into vessels shall meet these requirements:

a. Sufficiently rigid to prevent buckling.

b. Self-draining including "U" channel bracing or frames.

c. Adequate, conveniently located, and with welded, formed or crevice free 

handles. 

d. May or may not be gasketed. If the cover, door or panel is not gasketed, a 

downward flange of at least 3/8 (9.5mm) inch along all edges is required. 

e. Gasket material shall be solid. Open cell foam, smooth surfaced closed cell foam 

or hollow interior materials are not acceptable. 

f. Close fitting. 

g. The use of hinges, wing nuts, latches, and similar easy-opening fastening devices 

are recommended to allow easy access without special tools. 

h. Any hinges, wing nuts, latches, and similar easy opening fastening devices used 

shall be attached so as to minimize the use of fasteners and the creation of cracks 

and crevices. 

i. Hinges shall be of a sanitary design that can be readily disassembled. 

Continuous or piano-type hinges shall not be used on the equipment or its control 

cabinets.

j. This does not preclude use of piano type hinges on electrical boxes used on dairy 

processing equipment when they are located well outside of the product zone and 

not subject to product residues or repeated washing. 

k. Openings through a product contact surface shall have permanently attached 

sanitary connections or shall be flanged outward at least 3/8 in. (9.52 mm). 1

l. The personnel entry opening cover shall be of the inside or outside swing type. If 

the cover swings inside it shall also swing outside away from the opening for 

disassembly and cleaning. No threaded or ball joints shall be employed within 

the product zone to attach the cover and its appendages. The cover and its 

appendages shall be removable without tools. The cover for a top-entering 

opening shall be of the outside swing type only. 

m. Other openings shall have removable covers, which shall be pitched to the 

outside, and be downwardly flanged as noted in 10.19.G.d to make close contact 

with the edges of the outwardly flanged openings in the product contact surface. 

n. If braces or frames are made of hollow components, the integrity of the 

component shall not be compromised by drilling into the hollow interior. If 

bolting is required, studs welded to the exterior is the preferred method. 
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Alternatively, fully welded sleeves through the hollow frames or a fully welded 

blind tapped plug shall be employed to isolate the hollow interiors. 

o. Covers shall be designed so when in the open position, liquid from the exterior 

surfaces will not drain into the vessel. Also, when fully opened, drops of 

condensate on the underside will not drain into the vessel. 

p. Bridges and fixed covers shall slope to the outside edges of the tank for complete 

drainage and shall have a raised flange not less than 3/8 inch (9.5mm) in height 

where the edges meet the main covers. Bridges and fixed covers shall be integral 

or welded to the lining and shall be installed so the underside is accessible for 

cleaning and inspection without completely entering the vessel. Bridges shall 

not exceed 24 inches (610mm) in width. 

q. All non-permanently attached sanitary pipelines, agitators, and other 

appurtenances entering vertically through a product contact surface shall be fitted 

with a sanitary umbrella (downward curved) deflector that overlaps the edges of 

the outward flanged opening to prevent the entrance of contaminants (See 

Example r). 1

 (Example r) 1

 

r. Equipment that requires adjustment during operation shall be designed so 

adjustment can be made without the operator having to reach within the product 

zone through any entrance. 

s. Sample cocks, vacuum release valves or air release valves shall be of sanitary 

design and have a relatively flush interior sealing surface. They shall be easily 

dismantled for cleaning. Non-sanitary threaded fittings and valves are not 

acceptable.

UMBRELLA

DEFLECTOR NONPRODUCT

CONTACT

PRODUCT

CONTACT

SURFACE

MINIMUM 3/8"

PRODUCT

CONTACT

SURFACE

SHAFT

OR

VESSEL PIPE

TOP

ACCEPTABLE NOT ACCEPTABLE

DEFLECTOR DOES NOT PROTECTS HOLE WITH OFFSET SHAFT/PIPE

DEFLECTOR STILL PROTECTS

OPENING WITH OFFSET SHAFT/PIPE

DEFLECTOR DOES NOT PROTECT

OPENING WITH OFFSET SHAFT/PIPE

UMBRELLA

DEFLECTOR

TOO SMALL
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t. Dry products equipment shall be equipped with dust-tight covers or means for 

dust removal and control. 

10.20. Guards and Other Safety Devices

A. Guards required by personnel safety standards shall be removable for cleaning and

inspection of the equipment. Guards shall be designed to minimize the accumulation 

of debris and liquids 

10.21. Spray Devices

A. Spray devices that are left in place during production shall comply with the 

applicable 3-A Sanitary Standard 78-. 

B. Mechanical cleaning spray devices installed within a product contact area during 

processing operations shall be designed and installed to allow for easy removal for 

inspection and cleaning of spray holes or slits. 

C. Other devices, not of sanitary design, shall be removed after cleaning is completed 

and shall be designed and located to allow easy installation and removal. 

D. Holes in product contact surfaces for retaining pins shall be at least 5/32-inch (4mm) 

diameter.

10.22. Service Piping and Lines

A. Exposed braided coverings of cables or hoses shall not be used. 

B. Electrical and utility connections shall be as remote as practical from the product 

contact areas of the equipment. 

C. Exhaust air from pneumatic equipment shall be piped away from product and 

product contact surfaces.

D. Components using machinery fluids (e.g. lubricating and hydraulic fluids, and signal 

transfer fluids) shall be installed to prevent fluid ingress into the product or onto 

product contact surfaces.

E. Hose clamps of the enclosed worm gear type shall not be used. 

10.23. Culinary Steam and Piping

A. If the equipment provides for direct injection of steam into the product, the steam 

shall be produced in accordance with the 3-A Accepted Practice 609- “Method of 

Producing Steam of Culinary Quality”. 

B. The steam piping connection(s) to the product contact surfaces shall be made in such 

a way that product cannot enter the steam lines. All components downstream from 

the sanitary check valve shall be of sanitary design and be easily removable for 

cleaning and inspection. 
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10.24. Cylinders

A. Any part of the shaft of a pneumatic or hydraulic cylinder that enters the cylinder 

and extends over exposed product, or a product contact surface shall be provided 

with a sanitary shield or be of a sanitary design. Sanitary shielding can be 

accomplished with a long drip plate (so that all exposed product and product contact 

surfaces are shielded when the shaft is fully extended), or any other shield 

arrangement that protects the surfaces and product. A sanitary design may include; 

double seals (with 1-inch of clear space between them, provided the space between 

the seals is not in the product zone), doubling the length of the shaft so the part that 

enters the cylinder never extends over the product zone, or other sanitary design 

features.
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10.25. Hoses and Connectors

A. When a high-pressure hydraulic hose is located on a machine so that hose rupture 

could allow product contamination, that portion of the hose shall be enclosed in a 

larger secondary protective hose or tube, or other means to protect the product from 

contamination. 

B. Flexible connectors for dry products having product contact surfaces shall have 

straight sides without corrugations and shall be readily cleanable.

10.26. Gaskets, O-rings and Seals

A. Gaskets shall be removable or bonded. 

B. Bonded rubber, rubber-like materials and bonded plastic materials having product 

contact surfaces shall be bonded in a manner that the bond is continuous and 

mechanically sound. When exposed to the conditions encountered in the 

environment of intended use, cleaning and bactericidal treatment or sterilization, the 

rubber and rubber-like material or plastic material does not separate from the base 

material to which it is bonded.

C. Grooves in gaskets shall be no deeper than their width, except as appropriate for 

gasket sealing applications on large equipment. If the groove in the gasket is deeper 

than its width, the gasket shall be removable and reversible for cleaning. 
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D. Dimensions and profiles of gasket grooves or gasket retaining grooves for bonded 

gaskets are at the discretion of the fabricator.

E. Gasket retaining grooves for removable gaskets shall not exceed 1/4 in. (6.35 mm) in 

depth or be less than 1/4 in. (6.35 mm) wide except those for O-rings with crosssection dimensions 1/4 in. (6.35 mm) or smaller. Except that: 

a. For functional reasons, the depth of gasket retaining grooves of removable 

 gaskets shall be no deeper than the width. 

F. Gaskets between flat sealing surfaces shall create a substantially flush surface with 

the interior product contact areas. The juncture shall create a crevice free joint, 

without unsupported gasket material. (Refer to Section 10.5.C.)

G. Equipment designs with two or more O-rings or seals in a row between product 

contact and non-product contact surfaces shall have a leak-detection port between 

them that is open to the atmosphere and visible to the operator. The leak-detection 

port shall be a minimum of 1/8 in. (3.18 mm) in diameter. However, if this area is 

designed for disassembly and manual or COP cleaning, the leak detect port is not 

required. 

H. Gasketed joints employing recessed O-rings or seals which are intended for CIP 

shall be substantially flush so that a portion of the O-ring or seal surface will be 

partially exposed to cleaning solutions (See following illustrations of examples). 1
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10.27. Perforated Surfaces 1

A. Perforations located in a product contact area may be round, square, rectangular, or 

crescent-shaped. 

B. If round, the holes shall be at least 1/32 in. (0.794 mm) in diameter. 

C. If square or rectangular, the least dimension shall be at least 0.02 in. (0.51 mm) with 

corner radii of no less than 0.005 in. (0.127 mm). 

D. If crescent-shaped, the opening shall be at least 0.004 in. (0.102 mm) wide at the 

widest part and the perforations shall be at least 0.02 in. (0.508 mm) long. Internal 

angles of the perforations shall be well defined and free of crevices. One side of the

perforated component may have machine mark indentations around the perforations. 

The other side may have projections around the perforations, together with shallow 

open grooves between the rows of perforations.

E. All perforations shall be free of burrs.

F. Surfaces with perforations smaller than 1/32 in. (0.794 mm) shall be readily 

accessible and be designed for CIP cleaning.

10.28. Shafts 1

A. Shafts that pass through a product contact surface above the product level shall be 

designed to provide means to prevent the entrance of contaminants through the 

portion of the opening surrounding the shaft. 
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B. Shafts that pass through a product contact surface below the product level or 

designed to be located outside a processing area shall have a packless-type seal of 

sanitary design that is readily accessible and inspectable.

10.29. Bearings 

A. Bearings having a product contact surface shall be of non-mechanical, nonlubricated or product-lubricated type. (e.g. bushing, etc.) 

B. Lubricated bearings, including permanently sealed types, when used, shall be located 

outside the product contact surface with at least 1 in. (25.4 mm) clearance between 

the bearing and the nearest product contact surface or sanitary seal and such 

clearance shall be open for inspection (Refer to Section 10.17). 

11. Non-product Contact Surfaces

A. Non-product contact surfaces including frame assemblies, drive assemblies, 

mechanical actuators, support members, etc., shall be designed and fabricated so as 

not to contribute to unsanitary conditions. These areas are to be such that they do 

not detract from a clean environment for food processing. Primary concern shall be 

focused on those non-product contact surfaces which are in close proximity to 

product contact surfaces and may be subjected to product residues and splashing. 

Non-product contact surfaces which are located well outside of the product zone and 

not subjected to product residues and splashing do not have sanitary significance 

and should not be criticized for construction characteristics. In general, the further 

away from the product zone the less the non-product contact surfaces are to be 

criticized.

B. The following criteria shall apply only to those non-product contact surfaces which 

are subject to product residues and splashing: 

a. Non-product contact surfaces including frame assemblies shall be free of 

pockets and crevices and be readily cleanable. This can be attained by 

continuous welding, however, skip or strip welding may be employed 

provided that intervening crevices are suitably sealed or caulked. Although 

epoxy metal or silastic type caulking materials may be used for such sealing, 

it should be realized that this is usually only a temporary measure and that 

periodic maintenance will be required. Epoxy metal or silastic type caulking 

materials are significantly more durable when the materials can be applied to 

mating components prior to assembly. 

b. Where applicable, motor housings and hydraulic cylinders shall be isolated 

from product contact areas by sanitary shields or guards. (Note for 

Inspectors: when properly shielded or located where they are not subject to 

product residues and splashing, construction details of these components 

should not be criticized) See Section 11.A.
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c. Surfaces to be coated shall be effectively prepared for coating. This 

preparation may include, but is not limited to, grinding of welds, polishing of 

cast surfaces, cleaning of surfaces so the covering adheres properly, etc.

d. Stainless steel equipment frames and exterior non-product surfaces may be 

glass beaded if desired. If not made of corrosion-resistant metal, they shall 

be painted or coated. 

C. All non-product contact surfaces shall be of corrosion-resistant material or material 

that is rendered corrosion resistant. If the surfaces are coated, including painted 

surfaces, the coating shall adhere. All non-product contact surfaces shall be 

relatively nonabsorbent, durable, and cleanable. Parts removable for cleaning having 

both product contact and non-product contact surfaces shall not be painted. 

D. Non product contact surfaces shall have relatively smooth finishes and be relatively 

free of pockets and crevices. 

E. Permanent joints subject to product residue shall be continuously welded. Welded 

junctures do not require grinding or polishing. The following are acceptable methods 

of fabrication:

a. Exposed threads shall be minimized. The exposed threads shall not exceed 

one half the nominal diameter of the thread, except that:

1. Exposed threads that are subject to routine product splash during 

processing and cleaning shall be covered by an enclosed (Cap or 

Dome) nut. 

F. If the framework and exterior panels of the equipment are not made of corrosion 

resistant metal, they shall be painted or coated. When coatings are used, they shall be 

free from delamination, pitting, flaking, galling, blistering, or distortion when 

exposed to the conditions encountered in the environment of intended use. This 

includes cleaning and sanitizing. 

G. Where welding is not possible for functional or safety reasons, bolted joints may be 

used. When braces or frames are hollow, the integrity of the braces or frames shall 

not be compromised by drilling into the hollow interiors. Fully welded plugs into the 

hollow frame for blind holes or fully welded sleeves through the hollow frames shall 

be employed to isolate the hollow interiors. Studs welded to the exterior is preferred 

rather than bolting to or through the hollow frames. 

H. Knurled surfaces shall not be used in areas subjected to product residues and splash.

I. Recessed socket head bolts shall not be used, except that: 

- Recessed socket head bolts may be used provided they are away from any 

product (or splash) contact surfaces or

- may be shielded from any product residues or 

- mounted so that the socket heads drain. 

- Recessed socket head bolts may be used on rotating horizontal shafts.
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J. Blind Rivets (Pop Rivets) shall not be used. However, they are allowed on the 

nameplates of purchased parts. For example: Gear reducers, pneumatic cylinders, 

hydraulic cylinders, motors, electrical enclosures, instrument transmitter housings, 

cast components, etc.

K. When external lap joints for sheathing over insulated areas are used, they shall be 

overlapped downward, and overlapped joints shall be effectively sealed between the 

mating surfaces with suitable sealants. 

L. Control panels and electrical boxes shall be continuously welded to the surface to 

which they are mounted or, properly sealed with caulking material or mounted with 

approximate 1-inch (25mm) stand-offs. 

M. Hinges on control panels or electrical boxes shall not be the continuous or pianotype hinges. Except that: 

a. Piano type or continuous hinges on control panels or electrical boxes may be 

used when they are located remotely or well outside of the product zone and 

not subject to product residues or repeated washing 

11.1. Supports

A. Legs or casters shall provide a clearance between the lowest fixed point on the 

equipment and the floor of at least 4 inches (102mm) when the equipment base 

outlines an area in which no point is more than 12 1⁄2 inches (318mm) from the 

nearest edge of the base, or a clearance of at least 6 inches (152mm) when any point 

is more than 12 1⁄2 inches (318mm) from the nearest edge. 

B. Casters, if provided, shall be easily cleanable, durable, and of a size that will permit 

easy movement of the equipment. If bolted, excess threads should be cut off or 

covered with a "dome" type nut. 

C. Adjustable legs shall comply with the 3-A Sanitary Standard 88- (Machine Leveling 

Feet). 

D. Equipment with a closed base to be mounted on the floor shall have the base sealed 

in a bed of mastic or grouting. 

E. If mounted on a slab or island, the base shall be designed for sealing to the slab or 

island surface. The slab or island shall be of sufficient height so that the bottoms of 

all product connections are at least 4 in. (102 mm) above the floor. The mounting 

surface of the slab or island shall be coated with a suitable layer of waterproof 

mastic material, which will harden without cracking. The junction of the equipment 

base and the slab or island shall be sealed.

F. If mounted directly on a wall or column, the area of attachment of the equipment to 

its mounting surface shall be designed for sealing to the wall or column. If the 

design of the equipment is to be mounted offset from a wall or column it shall 
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provide at least a 4 in. (102 mm) clearance between the outside of the equipment and 

the wall or column.

G. Supporting structures, braces, catwalks, stairs, and handrails are not considered as 

non-product contact surfaces of the equipment but are considered as part of the 

building structure. 

11.2. Name and Information Plates 

A. Company name or information plates shall be fully bonded to the unit. Welding of 

metal plates or adhesive mylar stickers are preferred. However, plates may be 

bonded with a suitable adhesive or the crevice conditions may be sealed with 

caulking. The use of pop rivets is not acceptable. (Note for Inspectors: name plates 

on motors, gear drives, bearing bosses, actuating cylinders, etc., which are located 

outside of the area where they are not subject to product residues and splashing 

should not be criticized) Refer to Section 11.J.

B. Non-metallic, adhesive-backed name and information plates are also acceptable.

C. When an additional information plate is necessary to convey special information, it 

shall be attached in close proximity to the nameplate. Alternatively, this information 

may appear on the nameplate. 
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THE FOLLOWING SPECIAL 

CONSIDERATION SECTIONS

PROVIDE CRITERIA AND GUIDANCE 

IN ADDITION TO THOSE PROVIDED IN 

THE PREVIOUS SECTIONS. UNLESS 

SPECIFICALLY MODIFIED BY THESE 

SPECIAL CONSIDERATION SECTIONS, 

ALL MATERIALS AND FABRICATION 

CRITERIA IN SECTIONS 9 AND 10

APPLY.
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12. Special Considerations for Pasteurization Equipment

A. When the equipment or installation of a processing system includes a High 

Temperature Short-Time (HTST) or Higher Heat Shorter-Time (HHST) pasteurizer, 

USDA recommends that details of the proposed pasteurizer system be additionally 

presented for review and acceptance by the state regulatory agency responsible for 

inspecting, timing, and sealing the system upon installation. The state regulatory 

agency personnel receive training and guidance from the U.S. Public Health Service 

(USPHS), a federal agency of the Food and Drug Administration of the Department 

of Health and Human Services. DGB of USDA defers to USPHS for engineering 

expertise and leadership in the public health aspects of pasteurizer design and

operation. 

B. The "3-A Accepted Practice for the Sanitary Construction, Installation, Testing and 

Operation of High Temperature Short-Time and Higher Heat Shorter-Time (HHST) 

Pasteurizers, Revised," should be used as guidance for design and installation of 

HTST systems. Any new or unusual aspects of such systems should be presented for 

review to the state inspection agency or to the Milk Safety Branch, (HFF-346), FDA, 

Department of Health and Human Services, 330 C Street, S.W., Washington, DC 

20204. Telephone 202-205-8178, FAX 202-205-5560. 

13. Special Considerations for Exposed Product Conveyors 

Note:

Exposed product conveyors will be evaluated using the criteria of the 3-A Sanitary 

Standards for Mechanical Conveyors for Dry Milk and Dry Milk products; or the 

Sanitary Standards for Belt-Type Feeders as appropriate. 

However, exposed product conveyors which do not meet the scope criteria of the 

above referenced standards shall meet the following criteria.

A. Non-sanitary construction for drive mechanism components such as riveted roller 

type chains, cleated belts, round resilient belts, and friction drives may be considered 

as non-product contact surfaces provided one of the following methods of isolation 

is provided. 

a. Clearly identifiable boundary demarcations. A clearly identified demarcation 

 may include equipment intended to locate product in a set position on the 

 conveyor belt. These may include but not limited to a funnel or hopper, 

robotic arm, slicer, feed conveyor or other fitment that will locate all product in a 

 set position. 

b. A minimum of 1 inch (25mm) open clearance between the product contact area 

 and the drive components shall be required when the product contact area 

 boundaries are designated by closed construction such as close-fitting shields 

 enclosing the entire drive component section. 

B. Drive components and lubricated bearings with a minimum open clearance of 1 inch 

(25.4 mm) that are located in a position where product cannot touch these 

components and remain on the conveyor (e.g. bearings or drive components located 
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well below or outside of the product contact surfaces of the conveyor belt so the 

product cannot remain on the belting and touch these surfaces). 

C. Solid conveyor belts having direct product contact shall be endless. Metal stitching, 

clips or lacing are not acceptable methods of joining belt ends. 

D. Mechanical bearings that are capable of greasing shall be located at least 1 inch (25.4 

mm) from the sides of the conveyor. This area shall be open for inspection and 

cleaning.

E. Mechanical bearings of the permanent factory sealed type that are unable to be 

greased, may be located at least 1⁄2 inch (13 mm) from sides of the conveyor. Due to 

the limited amount of grease in the sealed bearing, migration from a failed bearing 

should be minimal. This area shall be open for inspection and cleaning. 

F. Belts which have absorbent core or backing material, that is woven and allows liquid 

wicking into the belt edges and backing material shall have these areas sealed with:

a. the same material as used for the product contact surface; or

b. a sealant which complies with the applicable Food and Drug Administration 

regulations for repeated food contact for the product which is being conveyed; or 

c. sealants applied that are equally as durable as the belting material and applied in 

sufficient thickness so that it shall remain intact without peeling, blistering, 

delaminating, flaking, etc., during the expected life of the belt. 

Note:

If it can be proven that liquids will not wick along the core or backing material 

fibers sealing the edges of the belt is not required. (Refer to item 13.Q)

G. When continuous, solid belting material is used for direct product contact, the area 

between the top and bottom runs of the belt and at the side frame areas may have 

non-sanitary construction. Provided that liquids, debris, or product residues are 

prevented from migrating onto or into product and/or product contact surfaces. 

H. The area between the belts may have exposed bolt heads (if needed for engineering 

reasons) and the welds need only to be continuous, pit and snag free, with no 

minimum radii or polishing requirements. Bolted junctures shall be gasketed so 

there are no crevices. This includes the bolt heads and cap nuts if used.

I. When modular type or open belting material is used for direct product contact, the 

area between the top and bottom runs of the belting material are considered to be 

product contact and meet all product contact criteria. Except that:

a. The areas between the top and bottom runs of the belt, and the side frame 

areas may have non-sanitary construction provided liquids, debris, or product 

residues are prevented from migrating onto the product contact surfaces by 

the use of sanitary constructed shields and guides. 
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J. Open belting and approved plastic link belting that weigh 50 pounds or less may be 

removed and placed in a COP tank for cleaning. If the belting weighs more than 50 

pounds or cannot be easily removed, shall be provided with an integral mechanical 

cleaning device(s) that are located so all exposed surfaces of the belting and 

sprockets are automatically cleaned. Cleaning solution catch pans or trays if used, 

shall be designed to be drainable and accessible for cleaning and inspection. 

K. Substitution of the integral mechanical cleaning device with manual cleaning 

techniques using hand-held high-pressure spray systems is unsatisfactory

L. Conveyor rollers for either direct product contact or for the support of belting 

material shall comply with the following criteria:

a. They shall be of sanitary design and constructed from acceptable materials.

b. Half knurled or slight roughened surfaces are acceptable.

c. Hollow rollers shall be completely sealed to prevent liquids from gaining 

access to interior voids.

d. End cap junctures shall comply with the permanent joint criteria of Section 

10.2. 

 

e. Rollers shall not contain integral lubricated, including sealed ball or roller 

style bearings. However, internally driven rollers may contain internal 

lubricated bearings. The internal drive rollers shall be of a sanitary design. 

Section 13.M. 

f. Recessed bushing or bearing surfaces shall be of sanitary design appropriate 

for mechanical cleaning or be readily removed for daily manual cleaning. 

g. The diameter of a recessed bearing cavity shall be greater than its depth.

M. Internally driven rollers shall be of sanitary design. The design shall assure that the 

internal lubricants cannot leak and contaminate product and the product contact side 

seals are of sanitary design. Each design proposal shall be evaluated on a case by 

case basis. 

N. Conveyors which run partially submerged in chilled brine systems are not required 

to meet the sanitary construction requirements. Bent wire conveyors and specified 

plastic link conveyors which are not acceptable for other exposed product conveyors 

may be acceptable for brine system discharge conveyors. Conveyors incorporating 

these designs will be evaluated on a case-by-case basis. The conveyors shall be 

designed so that lubricated bearings including the factory sealed type are not 

immersed in the brine and they can be removed from the brine for cleaning as 

needed. Such conveyors shall not be cleaned while immersed in the brine tank or 

flume unless the tank or flume has been drained. 

O. Flat top solid belting and modular link style belting for direct product contact shall 

be evaluated for acceptance on a case-by-case basis.
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P. When conveyors discharge into product hoppers or vessels, all bearings, drives and 

other non-sanitary areas located above shall be shielded to prevent contamination of 

the product in the hopper or vessel below. 

Q. Belting which includes fiber core or backing material shall be subject to a wicking 

test. Commercially available, water-based food coloring shall be the test solution. 

Undiluted food coloring shall be applied directly to the backing material and/or the 

cut edge of the belting for imbedded fibers. Any coloring penetration or migration 

along the fibers greater than 1 mm shall be considered evidence of unacceptable 

wicking properties of the materials.

 

14. Special Considerations for Packaging Machines 

Note:

The DGB utilizes the established 3-A SSI Sanitary Standards and Accepted 

Practices for equipment that fall under the scope of a particular standard or 

practice. In the event that the equipment reviewed, does not fully comply with 

the applicable 3-A SSI Sanitary Standards or Accepted Practice, the USDA 

Guidelines may be applied. If it can be determined that the equipment in 

question does not fully comply with the 3-A SSI Sanitary Standard or Accepted 

Practice but complies with the minimum requirements of the USDA Guidelines, 

USDA can still issue a letter of acceptance and certificate. 

A. Exposed product, product contact surfaces, or product contact surfaces of packaging 

materials shall have a sanitary design and protected from contamination from 

mechanical and non-product contact areas of the equipment. This may be 

accomplished by the proper design and use of catch pans or sanitary shields. 

14.1. Viscous and Dry Product Vertical and Horizontal Packaging Machines 

A. Film unwind assemblies, exposed threads, conventional air or vacuum fittings, 

folding assemblies or forming apparatus for packaging materials, suction cups to 

move packaging materials, cutting or slitting assemblies, arms or similar parts which 

extend over the product contact surface of the packaging material are not required to 

meet product contact criteria if they are kept dry during production and cleaning of 

the packaging. These parts do not have direct product contact, and there is little 

likelihood of contaminants or liquids draining from these surfaces onto product 

contact surfaces or dropping materials onto or into exposed product are not required 

to meet product contact criteria. 

a. Covers, shields or equally effective method may be used to ensure these areas 

remain dry during production and cleaning. (Appendix 8)

b. The materials of construction meet product contact requirements. For example; 

300 series stainless steel (except 301 and 302), or other acceptable metals or 

coatings, plastic or rubber materials complying with FDA Regulation 21 CFR 

part 170 through 199. 
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c. All welds shall be continuous, free of pits and snags. Polishing of welds is not 

required. 

d. There are no radii requirement for internal angles less than 135 degrees.

 

B. If the components noted in Section 14.1.A will be subject to wet washing, or liquid 

may drip onto product contact surfaces, onto the product contact surfaces of the 

packaging materials or into exposed product shall be considered as product contact 

and meet all product contact criteria. Alternatively, product contact surfaces, product 

contact surfaces of the packaging materials or exposed product may be isolated from 

the unsanitary surfaces above by sanitary designed shields, guards or catch pans. 

C. Conventional electrical wiring and connections for heat sealing clamps, bars, wheels, 

etc. shall be acceptable when their method of use, location, or sanitary shielding do 

not create unsanitary conditions contributing to the contamination of the product or 

product contact surfaces.

D. When a greased or sealed bearing is used in the end(s) of packaging material feed 

rollers, the bearings shall be a minimum open space of 1 in. from the edges of the 

packaging material or there shall be some other means of demarcation. This may 

incorporate the use of O-rings, drip edges, or grooves to isolate the surfaces of the 

rollers that contact the packaging material.

E. When engineering and fabrication exceptions are granted for intricate assemblies, 

they shall be designed to be readily removable for cleaning and inspection. 

F. Subassemblies designed to be removed and cleaned as a unit in a COP tank shall be 

designed so that all areas effectively clean. The subassemblies shall meet the 

following criteria:

a) The sub-assemblies shall be free of all crevices.

b) All bolted junctures that are not disassembled shall be gasketed to isolate the

threads and to prevent ingress of liquid and debris. 

c) Sub-assemblies may be loosened or partially disassembled to allow complete 

cleaning of the unit. 

d) Sub-assemblies that have product contact and painted non product contact 

surfaces shall not be cleaned in a COP tank.

e) Assemblies with greased or factory sealed bearings shall not be submerged 

and cleaned in a COP tank.

14.1.1. Vertical Fillers

A. Areas after the film has been formed around the filling tube and the film is 

overlapped and ready for heat sealing, will be evaluated for Good Manufacturing 

Practices (GMP). However, will not be required to be crevice free provided that the 

surrounding areas are kept free from product and/or residue. 

B. When liquid filling nozzles are a used, drip pans, shields or deflectors may be used 

to demarcate non-product contact areas from product contact areas below. GMP’s 
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will be required in these non-product contact areas located above the filling 

nozzle(s). However, the requirement to be free of crevices will not be required 

provided the surrounding areas are kept free from product and or residues. 

C. Product contact surface areas on the film feed (i.e. areas that touch the product side 

of the film or located above) will not be required to be crevice free as long as the 

areas are kept dry. This will require a special effort on the part of the equipment 

manufacturer and equipment users to ensure these areas stay dry during product runs 

and cleaning. Special guards, sheets, or covers, may be required. There shall be 

instructions in the owner’s manual on proper operation and cleaning of these areas. 

(Refer to the requirements noted in 14.1.A and 14.1.B)

D. Compressed air may be used to clean these areas. Compressed air shall comply with 

the 3-A Accepted Practice 604-. 

14.1.2. Horizontal Fillers

A. The areas after the container(s) have been formed and the film opening pulled tight 

closing the container; will not be required to be crevice free as long as the 

surrounding areas are kept free from product and/or residue.

B. Areas located above the film path after the folding plow where the film is pulled 

tight, are not considered to be product contact even though they are located above 

the folded film. 

C. All appurtenances that enter the folded film or formed container prior to filling (air 

nozzles, gas nozzles, etc.) shall be considered to be product contact and meet all 

product contact criteria.

D. All areas located above the formed container while held in the opened position from 

which materials may drop, drain or be drawn into the container shall be considered 

to be product contact and meet all product contact criteria or be shielded by a 

sanitary shield.

E. Product contact surface areas on the film feed (i.e. areas that touch the product side 

of the film or located above) will not be required to be crevice free as long as the 

areas are kept dry. This will require a special effort on the part of the equipment 

manufacturer and equipment users to ensure these areas stay dry during product runs 

and cleaning. Special guards, sheets, or covers, may be required. There shall be 

instructions in the owner’s manual on proper operation and cleaning of these areas. 

(Refer to the requirements noted in 14.1.A and 14.1.B)

15. Special Considerations for Cheese Brine Systems and Related Equipment

A. Stainless steel tanks should be made from 316 series stainless steel. A 2B mill finish 

is satisfactory. All welds shall be continuous, snag and pit free. Polishing of the 

welds is not required. There are no minimum radii requirements for internal angles

less than 135 degrees. 
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B. Concrete, concrete coated, or ceramic tile covered tanks shall have a smooth, 

cleanable interior surface. Exposed aggregate, pockets, bubbles, form impressions, 

missing grouting, flaking or galling of the surface is unacceptable. If a coating or 

sealer is used, it shall comply with the applicable FDA regulation 21 CFR Part 170 

through 199. 

C. Pit tanks shall have perimeter walls which extend at least 1 foot (305mm) above the 

floor level of the room. 

D. The design and construction of the wooden frames or other components for 

fiberglass tanks shall be substantial enough to bear the weight loading when the tank 

or flume system is filled with brine without stressing or breaking the fiberglass 

coating. 

E. The fiber glassed components shall be constructed with a final, resin rich coating 

that results in a smooth cleanable surface free of pits, checks, cracks, ripples or 

waves on both interior and exterior surfaces. 

F. All openings, bored holes for pipe or conduit passage, cut-outs, or attachments to the 

fiber glassed surfaces of the tank shall be fully sealed or fiberglass covered to 

prevent the entrance of moisture into the wooden frame.

G. When fiberglass tanks are stacked or "piggy-backed" the exterior of all but the 

lowest tank shall meet the same fabrication criteria as the interior surfaces of the 

tank which contact the brine and product. 

H. Stacked or "piggy-backed" tanks or flumes shall provide the following clearances: 

Between bottom of tank and floor. (Also applies to single level tanks or flumes)

Tank Width (in feet) Minimum Clearance (in inches)

Up to 3 (0.9m)

3 to 6 (0.9 - 1.8m) 

6 to 8 (1.8 - 2.4m) 

8 to 10 (2.4 - 3.0m) 

10 to 12 (3.0 - 3.7m) 

12 to 14 (3.7 - 4.3m) 

14 to 16 (4.3 - 4.9m) 

Over 16 (4.9m)

12 (305mm)

20 (508mm) 

22 (559mm) 

24 (610mm) 

26 (660mm) 

28 (711mm) 

30 (762mm) 

36 (914mm)

Note:

All tank measurements are exclusive of projecting ribs, cross beams, or top lips.

I. Between each tank and any tank above it shall be at least 18 inches (457mm), as 

measured between any projections or cross beams of the upper tank and the top lip 

of the lower tank except that, if the upper tank has ribs or cross beams which project 

downward 12 or more inches (305mm), the clearance shall be 24 inches (610mm). If 

the bottom tank is divided into narrow flumes (less than 20 inches (508mm) wide) 
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which interfere with movement in the bottom tank for manual cleaning, the 

clearance shall be 24 inches (610mm). 

J. Between the uppermost tank top lip and the ceiling of the room shall be at least 18 

inches (457mm). If there are ceiling joists or beams projecting downward there shall 

be compensating clearance to facilitate manual cleaning.

Note:

Lesser clearances may be considered if the brine tank or flume system is 

provided with a mechanical spray cleaning system.

K. Perimeter clearance between a tank or flume system and the walls of the room shall 

be at least 24 inches (610mm).

L. The aisle spacing between adjacent tanks shall be at least 24 inches (610mm), except 

that two long rectangular shaped tanks may be butted against each other on the long 

side in accordance with the following criteria:

a. There is at least 24-inch (610mm) aisle clearance on the remaining four 

sides.

b. The upper crevice between the two tanks is appropriately sealed. 

c. The underside contact points are properly sealed and form a flush surface 

with the bottom of the tanks. Deep recesses created by tank lips are 

unacceptable.

M. When fiberglass tanks or flumes are mounted directly on the floor, the following 

criteria apply:

a. The tank to floor juncture shall have a curved cove molding with at least a 1-inch 

(25.4 mm) radius to facilitate cleaning of the juncture. 

b. There shall be no mounting brackets for pipelines, electrical connections, etc., 

which breach the fiberglass integrity and would permit entrance of liquid into 

any interior void areas under the tank or flume.

c. The tank or flume system is mounted to permit access around the exterior for 

cleaning and inspection. 

N. When tanks or flumes are stacked or "piggy-backed", sanitary means shall be 

provided for personnel access to the upper tanks to prevent contaminants from 

entering the lower tanks. 

O. Provision shall be made so the brine can be pumped out of the system so the tanks or 

flumes can be cleaned. Separate brine storage tanks or product storage tanks may be 

used. 

P. Plastic or rigid PVC piping suitable for potable water systems may be used for the 

transport of brine. Brine piping shall be rigidly supported and self-draining. 

Q. Butterfly type valves are acceptable for use on brine distribution piping.
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R. Threaded fittings may be used for brine spray nozzles. 

S. Pumps complying with the criteria within the 3-A Accepted Practices for 

Permanently Installed Sanitary Product-Pipelines and Cleaning Systems, Used in 

Milk and Milk Products Processing Plants for circulating cleaning solutions are 

satisfactory. However, food grade pumps may be used on purified brine which does 

not contain dairy solids or particulate.

T. Specially constructed Archimedes screw or jet type pumps may also be used 

provided that the construction materials are corrosion resistant and there are no 

lubricated bearings above or under the brine surface. All motors, drive assemblies, 

lubricated bearings, etc., shall be appropriately isolated or shielded to prevent 

contamination of the brine. 

U. Baffles, gates, baskets, frames, racks, and other appurtenances shall be mechanically 

sound, sufficiently strong for the intended use, and corrosion resistant. Parts shall not 

be painted. Threaded and bolted construction, woven plastic or stainless-steel screen 

material, and braided stainless steel cables are satisfactory. There are no minimum 

radii requirements.

V. Baskets, frames, or racks which are removed from the brine for cleaning and storage 

or staging for loading shall not be stored on the floor. Sanitary storage racks or 

platforms shall be provided.

W. Systems shall have facilities, suitable to their size, for skimming, filtering, cooling, 

and adjustment of brine strength. Pasteurization or ultraviolet (UV) treatment of the 

brine is encouraged.

X. A hoist(s), if used, shall have all non-sanitary surfaces such as the drive, hoist 

chain, cables, pulleys, rollers, etc., provided with a sanitary shield(s) to protect any 

exposed product, product contact surfaces, or brine below the hoist. 

16. Special Considerations for Cheese Molds

A. All mold surfaces are to be considered product contact surfaces as most users

routinely save cheese whey solids and butterfat for human consumption. 

B. The radius requirements of Fabrication Items 10.12 A-G shall apply except when 

required for:

a. Bending of thin, smooth or perforated metal sheets of 16-gauge

thickness or thinner. In such instances, internal radii shall be not less

than 1/32 inch (0.8 mm) and the short side of a 180-degree bend shall

not exceed 3/8 inches (9.5mm) in length. See Figure J.1 for an example 

of an acceptable formed stiffening rim on the top of a metal cheese

mold. 
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 Figure J.1 

b. Maintaining the desired shape of the cheese.

c. Functional requirements during the molding, cooling, mirror welding or 

friction welding of plastic components. 

C. When close tolerance areas are required for functional reasons, perforations shall 

be located to facilitate cleaning. See Figures J.2 and J.3 for examples of 

alternate placement of required perforations.
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Figure J.2 Figure J.3

D. Mechanical cleaning is required when component perforations are 1/32 inch (0.8 

mm) or less in diameter, or when component parts such as a bonded plastic cheese 

cloth are cleaned as assembled units.

E. All component parts are to be fully accessible for inspection or cleaning. 

Demountable parts are to be readily demountable. There shall be no non-inspectable 

surfaces.

F. When air pressure is used for release of the cheese from the mold, the air supply 

shall comply with the 3-A® Accepted Practices for Supplying Air Under Pressure in 

Contact with Milk, Milk Products and Product Contact Surfaces, Number 604-. 

16.1. Stainless Steel Molds

A. Non-perforated metal components shall be continuously welded, ground and 

polished as required by Sections 10.1.A. and 10.1.B. and 10.2.A. 

Figure J.2 Perforations in a formed 

stiffening rim on the top of a metal 

cheese mold is required at one or more 

of locations A, B, or C to facilitate 

cleaning.

A. Cheese mold body

B. Perforated drain screen on inside

C. Required perforation for cleaning

D. Perforations for whey drainage
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B. Spot welding of perforated screen material may be utilized in accordance with the 

following criteria (See Figure J.4):

a. The weld shall be at the apex of a preformed dimple in the screen.

b. The entire apex surface of the dimple shall be welded.

c. Spot welded perforated screens shall be separated by at least 1/16 inch 

(1.5mm). 

d. The preformed dimple in the screen shall be no deeper than its width. 

C. Glass beading of molds is acceptable under the guidance of Section 10.1.E. 

D. Component parts may be held together (spring tension, positioning pins, "R" clips, 

etc.) during routine use and cleaning procedures. See Sections 16.C, 16.D, and 16.E. 

16.2. Plastic Molds

A. All plastic molds shall require mechanical cleaning.

B. Mold strengthening ribs, especially those located on mold lids, shall not create nondrainable pockets or other obstructions to free draining. 

C. Fabrication materials shall comply with Section 9.1.E and 9.1.F. 

D. When heat, ultrasonic or chemical welding is used to attach plastic components, 

all deformed material shall be removed to eliminate any cracks, crevices, pits or 

folds. No radius is required at these junctures.

E. All injection sites, perforations, machined surfaces, etc. shall be free of ripples, 

distortion, flashing, loose strings or shavings of plastic. 

F. Plastic colors shall comply with the applicable FDA regulations.
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G. When plastic components are used in conjunction with stainless steel components, 

all assemblies shall comply with 16.2.C, 16.2.D and 16.2.E. Components shall fit 

loose enough to allow movement that will permit cleaning solution to flow between 

the stainless and plastic components so there are no non inspectable areas. 

H. Mold parts shall not be fastened together with non-sanitary threaded fasteners. If 

sanitary threaded fasteners are used, complete disassembly for manual cleaning will 

be required. 

I. Textured surfaces of the mould interiors necessary for the proper draining and 

texture of the cheese block exterior will be evaluated on a case-by-case basis. 

16.3. Mold Washing Devices: (Non-Recirculating Type) 

A. All washing devices shall be equipped with automatic temperature controls. 

B. Automatic solution concentration and addition controls are encouraged. 

C. Mold washing devices shall be constructed of stainless steel.

D. Mold washing devices are exempt from the requirements of fabrication Sections 

10.1.A, 10.12.A-G, and 10.26.E. 

E. All interior surfaces including bolted construction shall be free of all cracks and 

crevices. All bolted construction should be avoided. However, if for functional 

reasons bolted construction is required, all bolted junctures shall have no exposed 

threads, crevices and shall be gasketed including the bolt heads and dome nuts. 

F. The exposed threads in the interior of the washing unit shall be avoided. Except that: 

a. Threaded fittings may be used for spray nozzles and 3-A Sanitary fittings. 

G. All internal welds of the mold washing device shall be smooth, pit, and snag free. 

Grinding and polishing of welds is not required.

* Non-Recirculating Type means a self-contained unit that is not connected to a 

central CIP system. The cleaning solution is dumped daily and not saved for day 

to day usage.
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17. Special Considerations for Mechanical Cleaning Systems for Large Equipment or 

Vessels

Note: 

These guidelines are not intended for the construction of small parts washers, 

COP tanks or cheese mold washers

A. All appropriate sections of these guidelines apply to large vessels or equipment 

designed and fabricated for mechanical cleaning. Special attention shall be placed 

on: 

 

a. Interior product contact surfaces shall be self-draining except for normal 

adherence. When for essential functional or safety reasons self-draining is not 

possible, the equipment shall be drainable.

b. Equipment bottoms shall be constructed so they will not sag, buckle, or prevent 

complete drainage. The bottom slope of equipment which is 6 feet (1829mm) in 

diameter or lineal distance from a drainage outlet or less shall be at least 1/4 inch 

(6.35 mm) per foot (305mm). The bottom slope of equipment which is greater 

than 6 feet (1829mm) in diameter or lineal distance from a drainage outlet shall 

be at least 1⁄2 inch (13mm) per foot (305mm).

c. The equipment design shall assure that all product contact surfaces will be free 

of cracks, crevices and dead-end areas that would impede cleaning. Also, the 

prescribed mechanical cleaning procedure shall be proven to effectively clean the 

equipment. 

d. If mechanical cleaning is intended to clean only portions of the equipment, the 

operator's manual shall clearly identify those components which require 

disassembly, removal, and manual cleaning. 

e. All equipment utilizing mechanical cleaning shall be designed so it can be easily 

opened periodically to inspect that all product contact surfaces are being 

adequately cleaned. Also, to provide easy access to all internal gasketed surfaces 

to allow gasket replacement and proper gasket maintenance.

f. All product contact surfaces shall be easily accessible for inspection and 

cleaning, either when in an assembled position or when removed. Removable 

parts shall be readily demountable.

g. All product and cleaning solution pipelines, sanitary pipe fittings, valves, 

instrument fittings, appurtenances, and components which are part of the 

equipment shall comply with applicable 3-A Sanitary Standards or 3-A Accepted 

Practices as appropriate.

h. Hinges for access ports and covers of equipment shall be demountable and 

readily cleanable. Continuous or piano type hinges are unsatisfactory.
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i. Mechanical cleaning spray devices installed within a product contact area to be 

left in place during production shall comply with the applicable 3-A Sanitary 

Standard 78-. 

j. Spray devices not of sanitary design, shall be removed after cleaning is 

completed and shall be designed and located to allow easy installation and 

removal.

B. Equipment and appurtenances included in a mechanical cleaning system for large 

vessels or equipment for which there are applicable 3-A Sanitary Standards shall 

comply with all criteria within those standards except as specifically exempted by 

this section. 

C. The mechanical cleaning system shall include a mechanical cleaning unit dedicated 

to and used exclusively for the supply and recirculation of cleaning or sanitizing 

solutions. The mechanical cleaning unit may be provided as an appurtenance to the 

equipment or may be an existing unit provided by the processing facility. The 

mechanical cleaning unit may include but is not limited to the following:

a. Cleaning and sanitizing solution pump(s);

b. Cleaning and sanitizing solution tank(s);

c. Cleaning and sanitizing solution supply and return valve(s) and valve 

manifold(s);

d. Fittings;

e. Cleaning and sanitizing solution heat exchanger(s) or steam injector(s);

f. Instrument fitting(s) and;

g. Strainers.

D. All cleaning and sanitizing solution contact surfaces included in recirculation 

cleaning circuits shall comply with the materials, design and finish requirements of 

product contact surfaces, except for those of castings for cleaning and sanitizing 

solution heat exchanger(s)/steam injector(s).

E. A No. 2B finish shall be considered as acceptable for all cleaning and sanitizing 

solution contact surfaces.

F. Castings for cleaning and sanitizing solution contact surfaces shall be at least as 

smooth as an Alloy Cast Institute (ACI) Surface Indicator Scale SIS-1. 

Copies of the SPECIFICATIONS FOR VISUAL INSPECTION OF CAST 

SURFACE FINISH as well as the SURFACE INDICATOR SCALE can be 

obtained from the Alloy Casting Institute Division, Steel Founders' Society 

of America, Cast metal Federation Building., 455 State Street, Des Plaines, 

IL 60016, 70829-99160.

G. Appurtenances, such as plug valves, instrument fittings, sample cocks, pumps, or 

other specified components not designed to be mechanically cleaned shall be readily 

demountable and easily disassembled for manual cleaning and sanitizing. Operator 

instruction manuals provided with the equipment shall identify all such 
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appurtenances or parts requiring supplemental manual cleaning and provide 

instructions for their disassembly.

H. There shall be no exposed threads on cleaning and sanitizing solution contact 

surfaces.

I. Cleaning and sanitizing solution pumps designated solely for mechanical cleaning 

recirculation shall be provided with an information plate permanently affixed to the 

pump, next to the name plate stating: "This pump shall be used solely for pumping 

cleaning and/or sanitizing solutions". 

J. All valves to be included in the mechanical cleaning system shall be provided with 

automatic actuators which shall be programmed to pulse during the cleaning cycle so 

that all product contact surfaces of the sealing face and the gaskets are adequately 

cleaned.

K. All manually operated valves shall be disassembled and manually cleaned during 

each cleaning cycle. 

L. Each separate cleaning circuit, including product and cleaning and sanitizing 

solution lines, shall be provided with sufficient access points, such as valves, fittings, 

or removable sections to make possible adequate inspection and examination of 

representative interior surfaces.

M. The mechanical cleaning unit shall be designed so the suction intake of the primary 

circulating pump shall be flooded at all times during the cleaning cycle. 

N. Cleaning solution temperature shall be automatically controlled using a temperature 

control system with a response range of +/- 5 degrees F (+/- 3 degrees C). The 

temperature control sensor shall be located in the cleaning solution return line. 

O. There shall be no cross-connections between any cleaning / sanitizing solution 

circuit and any product circuit. Provisions shall be made to effectively separate and 

positively prevent the commingling of product and cleaning and sanitizing solutions 

during processing. This may be accomplished by the use of a properly designed 

Block, Bleed, Block valving assembly, a 3-A compliant mix-proof valve(s) or a 

physical disconnect. 

P. Connection of the mechanical cleaning unit and the safe water supply shall meet all 

installation codes of the appropriate regulatory agency.

Q. Reverse osmosis permeate or cow water (condensed vapors removed from liquid 

dairy products by vacuum evaporation) produced in compliance with USDA criteria 

may be used as a pre-rinse directed to drain or to make up cleaning solutions. 

However, this water cannot be used as a final rinse or to make up sanitizing solutions 

unless specifically approved by the appropriate State water control regulatory 

authority and USDA. Approvals of this nature shall be handled on a case by case 

basis.
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18. Special Considerations for Lactose Equipment

A. Product contact surfaces upstream from the point where the dairy fats and solids are 

removed from the mother liquor shall meet the requirements for sanitary design, 

materials and fabrication of dairy processing equipment as outlined in sections 9 and 

10. For example, the point of dairy fat and solids separation in a lactose centrifuge 

occurs as the mother liquor passes through the basket screen. 

B. Product contact surfaces from which liquids may drip, drain or be drawn into contact 

with the separated dairy fat and solids shall also meet the requirements for sanitary 

design and construction of dairy processing equipment as stated in item A above. 

This may include some surfaces downstream from the point where the dairy fats and 

solids are removed from the mother liquor. 

C. Surfaces in contact with lactose crystals and from which liquids will not drip, drain 

or be drawn into the dairy by-products may be constructed using the following 

criteria:

a. Equipment shall be constructed of non-toxic material meeting applicable 

Food and Drug Administration regulations. The materials shall be resistant 

to corrosion, pitting and flaking. The use of stainless steel is recommended 

but optional. 

b. A 2B mill surface finish is accepted on lactose contact surfaces made of 

stainless steel. Surface finishes equivalent to a number 4 finish are not 

required. 

c. Welds should be continuous, relatively smooth and free of pits, folds and 

snags. Where necessary for functional reasons, skip welds may be used. 

Grinding and polishing of welds is not required. 

d. Minimum radii of internal angles of less than 135 degrees are not required. 

However, it is recommended that sharp corners be avoided.

e. Bolted construction and exposed threads are acceptable on dry lactose 

applications
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19. Validation of Prior Acceptance

A. An Applicant who has any model of equipment or component which has 

successfully completed the review and evaluation process and is published in the 

Accepted Equipment Listing is required to re-validate its acceptance every five 

years.

B. If the applicant wishes to renew their Certificate of Acceptance, prior to the 

expiration of the current Certificate of Acceptance, the Applicant shall provide a 

letter or e-mail requesting to renew their certificate.

The letter or e-mail should contain the following: 

 1. Name and address of the company requesting the renewal.

 2. USDA project number. 

 3. All model(s) and/or model number(s) listed on the current certificate.

 4. Changes to the design or materials of construction. 

a. If there have been no changes, the letter shall 

reflect that no changes have been made to the 

design or materials of construction since the 

previous Certificate of Acceptance was 

issued.

 5. Name of person requesting the renewal for the applicant 

20. Resolution of Reports of Noncompliance

A. When a question arises as to whether a piece of USDA Accepted equipment 

complies, a user, fabricator, or other interested party may submit a letter of 

complaint to the Chief of the DGB via mail, facsimile, or e-mail at:

USDA, AMS, Dairy Programs Dairy Grading Branch 

Design Review Section Room 2746 - South Building 

1400 Independence Avenue, SW STOP 0230 

Washington, DC 20250-0230 

Phone: (202) 720-3171 

Fax: (202) 720-2643 

Email: Dairynfo@usda.gov (Atten: Branch Chief)

B. The letter or e-mail should contain the following: 

1. The party making the complaint

2. The address and phone number of the complainant 

3. The name or type of equipment or utensil in question 

4. Where the equipment or utensil is located
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5. The equipment or utensil manufacturer 

6. The model number and serial number (if known) 

7. The specific reason(s) for suspecting noncompliance (reference the 

standard if known) 

Examples: 

Improper finish on product contact surfaces, piano-style hinge on cover, tack 

welds on exterior surfaces, or unacceptable materials used for construction. 

(Noncompliance is not limited to the examples.)

C. The DGB, Equipment Review Staff will act in an expeditious manner to 

determine the validity of the complaint, and if it is determined to be valid, who 

is the responsible party.

21. Equipment Manufacturer Responsibilities

A. If the equipment manufacturer is determined to be the responsible party and 

they agree to correct the noncompliance issue, they are to submit an 

Equipment Review Request (See Exhibit 1) to initiate a USDA review of the 

corrective actions. The DGB will then determine with the manufacturer a 

mutually agreeable time in which to correct the noncompliance of the 

identified piece of equipment and, if necessary, of all like items in the 

marketplace with the same deficiency. While the corrections are being made, 

the USDA Acceptance will continue uninterrupted. Additionally, the 

manufacturers will provide documentation on their quality control procedures 

to assure that the noncompliance will not recur. 

B. If the equipment manufacturer is determined to be the responsible party and 

they decide not to correct the noncompliance, they will be notified that the 

USDA Acceptance for the equipment is withdrawn. Notification of the 

withdrawal of USDA Acceptance will be provided to the Food Safety and 

Inspection Service (FSIS), State regulatory officials, and appropriate Trade 

Associations.

 

C. The manufacturer is responsible for all costs associated with 

evaluation of the resolution of the noncompliance. 

22. Equipment User Responsibilities

A. If the equipment user is determined to be the responsible party and they 

agree to correct the noncompliance, they are to submit an Equipment 

Review Request (See Exhibit 1) to initiate a USDA review of the 

corrective actions. The DGB will determine with the user a mutually 

agreeable time in which to correct the noncompliance. While the 

corrections are being made, the USDA Acceptance will continue

uninterrupted. 
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B. If the equipment user is determined to be the responsible party and they 

decide not to correct the nonconformance, they will be notified that the 

USDA Acceptance for their specific piece of equipment (Serial Number)

is withdrawn. Notification of the withdrawal of USDA Acceptance will be 

provided to the FSIS, State regulatory officials, appropriate Trade 

Associations, and the equipment manufacturer.

 

C. The user is responsible for all costs associated with evaluation of the resolution 

of the noncompliance.

23. Appendix

23.1. Stainless Steel and Equivalent Materials

A. Stainless steel conforming to the applicable composition ranges established by 

AISI A959 or AIST Stainless Steels: A Steel Products Manual for wrought 

products or by ACI for cast products, for wrought products, or by ACI for cast 

products, should be considered in conformance to the requirements of Section 

D2 herein. Cast grades of stainless-steel corresponding to types 302, 304, and 

316 are designated CF-16F, CF-8, and CF-8M, respectively. The chemical 

compositions of these cast grades are covered by ASTM specifications 

A351/A351M, A743/A743M and A744/A744M 

TABLE 1 

WROUGHT PRODUCTS TYPICALLY USED

UNS #

Grade 

Designation 

ASTM 

Material 

Standard 

Pub. No.

AISI/SAE 

Grade 

Designation 

Properties

ASTM 

Grade 

Designation

S30300 A582 303 Free-Machining 

S.S.; Austenitic 303 

S30400 A276

A666 304 Austenitic S.S. 304 

S30403 A276 

A666 304L Low Carbon Austenitic S.S. 304L 

S31600 A276 

A666 316 Austenitic S.S. plus Mo* 316

S31603 A276 

A666 316L 

Low Carbon

Austenitic S.S. 

plus Mo*

316L 
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*Molybdenum 

TABLE 2

CAST PRODUCTS

UNS #

Grade Designation

ASTM

Material 

Standard 

Pub. No.

ACI

Grade 

Designation

Common

Names

J92500 

A351

A743 

A744

CF-3 Cast 304L 

J92800 

A351

A743 

A744

CF-3M Cast 316L 

J92600 

A351

A743 

A744

CF-8 Cast 304 

J92900 

A351

A743 

A744

CF-8M Cast 316 

J92180 A747 Nb7 Cu – 1 Cast 17-4 PH

J92110 A747 Nb7 Cu –2 Cast 15-5 PH

N26055 A494 CY5Sn BiM Alloy 88

J92701 A743 CF-16F Free Machining

Austenitic S.S.
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TABLE 3 - OPTIONAL METAL ALLOYS

Optional metal alloys having the following compositions are examples considered in compliance 

with Section 9 herein. (Percentages are maximums unless range is given.)

UNS

N0836

7

UNS

S2180

0

UNS

S2016

1

UNS

N2605

5

UNS

N2645

5

UNS

S1740

0

UNS

S1550

0

UNS

S3290

0

UNS

R2050

0

UNS

R5040

0

ASTM

A743 

Mat=l 

Std

CN3MN 

ASTM

A743 

Mat=l 

Std

CF-10 

SMnN

ASTM

A494 

Mat=l 

Std

CY5Sn

BiM

ASTM

A494

Mat=l 

Std

CW2M 

ASTM

A747 

Mat=l 

Std

Nb7Cu

-1 

ASTM

A747 

Mat=l 

Std

Nb7Cu

-2 

ASTM 

A560 

Mat=l 

Std

50Cr50Ni

ASTM

B67

Mat=l 

Std

C-2 

Com. 

Name AL6XN7

Nitroni

c-60

GallTough Alloy 

88

Hastell

y-C7 17-4 

PH

15-5 

PH

329 

Duplex 50/50 Titaniu

m

C 0.03 0.10 0.15 0.05 0.02 0.07 0.07 0.08 0.10 0.10

Mn 2.00 7.00-9.00 4.00-6.00 1.50 1.00 0.70 0.70 1.00 0.30

Si 1.00 3.50-4.50 3.00-4.00 0.50 0.80 1.00 1.00 0.75 1.00

P 0.04 0.04 0.04 0.03 0.03 0.035 0.035 0.04 0.02

S 0.01 0.03 0.04 0.03 0.03 0.03 0.03 0.03 0.02

Cr 20.0-22.0 16.0-18.0 15.0-18.0 11.0-14.0 15.0-17.5 15.5-17.5 14.0-15.50 23.0-28.0 48.0-52.0

Ni 23.5-25.5 8.00-9.00 4.00-6.00 Balance Balance 3.60-4.60 3.50-5.50 2.50-5.00 Balance 

Mo 6.0-7.0 2.0-3.5 15.0-17.5 1.00-2.00

Nb 0.15-0.35 0.15-0.35

Cu 0.75 2.50-3.20 2.50-3.20

N 0.18-0.26 0.08-0.18 0.08-0.20 0.05 0.05 0.30 0.03

Fe Balance Balance Balance 2.00 2.00 Balance Balance Balance 1.00 0.30

Sn 3.0-5.0

Bi 3.0-5.0

W 1.0

Ti 0.50 Balance 

Al 0.25

Other H = 0.015

O = 0.25
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Metal alloys or metals other than the those noted in the previous table may be as corrosion resistant as 300 Series 

Stainless Steel. This may be shown when metal alloys or metals are tested in accordance with ASTM G31 Laboratory 

Immersion Corrosion Testing of Metals and have a corrosion rate of less than 10.0 mil per year. The test parameters,

including the type of chemical(s), their concentration(s), and temperature(s), should be representative of cleaning and 

sanitizing conditions used in equipment. Alloys containing lead, leachable copper, or other toxic metals are not to be 

used.

23.2. Electroless Nickel Alloy

A. An electroless nickel alloy coating having the following composition is deemed 

to be in compliance with section 8.2.10 herein: 

1. Nickel - 90% minimum,

2. Phosphorous - 6% minimum and 10% maximum as a supersaturated 

solution of nickel phosphide in nickel, 

3. Trace amounts of carbon, oxygen, hydrogen, and nitrogen, 

4. No other elements allowed. 

TABLE 4 - Linear Conversion (in. to mm)

IP (in.)

fraction

IP (in.)

decimal

SI

(mm)

IP (in.)

fraction

IP (in.)

decimal

SI

(mm)

IP (in.)

fraction

IP (in.) 

decimal

SI

(mm)

1/32 0.03125 0.794 33/64 0.515625 13.10 1 1 25.40

3/64 0.046875 1.19 17/32 0.53125 13.49 1-1/4 1.25 31.75

1/16 0.0625 1.59 35/64 0.546875 13.89 1-1/2 1.50 38.10

5/64 0.078125 1.98 9/16 0.5625 14.29 1-3/4 1.75 44.45

3/32 0.09375 2.38 37/64 0.578125 14.68 2 2 50.80

7/64 0.109375 2.78 19/32 0.59375 15.08 2-1/4 2.25 57.15

1/8 0.125 3.18 39/64 0.609375 15.48 2-1/2 2.50 63.50

9/64 0.140625 3.57 5/8 0.625 15.88 2-3/4 2.75 69.85

5/32 0.15625 3.99 41/64 0.640625 16.27 3 3 76.20

11/64 0.171875 4.37 21/32 0.65625 16.67 3-1/4 3.25 82.55

3/16 0.1875 4.76 43/64 0.671875 17.07 3-1/2 3.50 88.90

13/64 0.203125 5.16 11/16 0.6875 17.46 3-3/4 3.75 95.25

7/32 0.21875 5.56 45/64 0.703125 17.86 4 4 101.6

15/64 0.234375 5.95 23/32 0.71875 18.26 4-1/2 4.50 114.3

1⁄4 0.25 6.35 47/64 0.734375 18.65 5 5 127.0

17/64 0.265625 6.75 3/4 0.75 19.05 5-1/2 5.50 139.7

9/32 0.28125 7.14 49/64 0.765625 19.45 6 6 152.4

19/64 0.296875 7.54 25/32 0.78125 19.84 7 7 177.8

5/16 0.3125 7.94 51/64 0.796875 20.24 8 8 203.2

21/64 0.328125 8.33 13/16 0.8125 20.64 9 9 228.6

11/32 0.34375 8.73 53/64 0.828125 21.03 10 10 254.0

23/64 0.359375 9.13 27/32 0.84375 21.43 12 12 304.8

3/8 0.375 9.52 55/64 0.859375 21.83 15 15 381.0

25/64 0.390625 9.92 7/8 0.875 22.22 18 18 457.2

13/32 0.40625 10.32 57/64 0.890625 22.62 20 20 508.0
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27/64 0.421875 10.72 29/32 0.90625 23.02 24 24 609.6

7/16 0.4375 11.11 59/64 0.921875 23.42 25 25 635.0

29/64 0.453125 11.51 15/16 0.9375 23.81 30 30 762.0

15/32 0.46875 11.91 61/64 0.953125 24.21 35 35 889.0

31/64 0.484375 12.30 31/32 0.96875 24.61 36 36 914.4

1⁄2 0.500 12.70 63/64 0.984375 25.00 40 40 1016.0

TABLE 5 - Linear Conversion (in. to cm; ft to m)

IP (in.) SI (cm) IP (in.) SI (cm) IP (ft) SI (m) IP (ft) SI (m)

45 114 75 190 10 3.05 35 10.7

48 122 80 203 12 3.66 36 11.0

50 127 84 213 15 4.57 40 12.2

55 140 85 216 18 5.49 50 15.2

60 152 90 229 20 6.10 60 18.3

65 165 95 241 24 7.32 70 21.3

70 178 96 244 25 7.62 80 24.4

72 183 100 254 30 9.14 90 27.4

TABLE 6 - Volumetric Capacity Conversion (gal to L)

IP 

(gal) SI (L) IP (gal) SI (L) IP (gal) SI (L) IP (gal) SI (L)

1 3.78 200 757.0 1,000 3,785 7,500 28,388

5 18.93 300 1,136 1,500 5,678 10,000 37,850

10 37.80 400 1,514 2,000 7,570 20,000 75,700

15 56.80 500 1,892 2,500 9,462 30,000 113,550

20 75.70 600 2,271 3,000 11,355 40,000 151,400

25 94.60 700 2,650 3,500 13,248 50,000 189,250

100 378.50 800 3,028 4,000 15,140 75,000 283,875

150 567.80 900 3,406 5,000 18,925 100,000 378,500

175 662.40
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TABLE 7 - Flow Rate Conversion (gpm to Lpm) 

IP (gpm) 9.4 24.0 43.0 69.0 102.0 182.0 5 ft/s

SI (Lpm) 35.6 90.8 163.0 261.0 386.0 689.0 1.5 m/s 

24. Instruction Handbook, Maintenance, and Cleaning

A. The instruction handbook includes the following items: 

24.1. Installation of the Equipment and Associated Equipment

A. Information is provided so that, after the equipment is installed, it maintains its

hygienic integrity (e.g., drainability and Inspectability).

24.2. Instructions for Use 

A. Measures are described on the use of the equipment so that when used correctly 

the product is not exposed to factors that can lead to contamination. 

24.3. Maintenance 

A. A system of measures is recommended to ensure that the hygienic integrity of 

the equipment is maintained during the intended lifetime. This information 

should include specific gasket, seal or O-ring materials where they are used 

because of product characteristics (e.g. high fat or high acid) or operational 

characteristics (e.g. vacuum or steam applications or when used to create a 

bacterial tight seal between product contact surfaces and non-sanitary threads).

24.4. Cleaning 

A. The instructions specify typical routine procedures for cleaning, sanitizing, 

rinsing, and inspection for cleanliness and, where appropriate, sterilization. 

Recommended cleaning and sanitizing procedures, materials, implements, and 

agents should be specified. Recommended cleaning and sanitizing procedures, 

materials, implements, and agents shall be compatible with the materials of 

construction. Where dismantling is required, specific instructions shall be 

provided. 
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24.5. Special Cleaning Instruction

A. Cleaning of areas of the equipment that are not to be subjected to normal 

washdown or wet cleaning. (e.g. film unwind areas and container forming 

assemblies). 

B. Type of cleaning chemicals and cleaning regimen that is to be used on the 

materials of construction for the piece of equipment. 

C. Areas of the equipment or assemblies that require disassembly and manual 

cleaning.

D. Special tools that are to be used for cleaning of the equipment. (e.g. no metal 

scrapers, etc)
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25. History 

Version Description/[Reason]

Current Document: CPPS-00.00.00.00-POP-CF-M-v20201110

DATE 20201110

Previous Document(s)

USDA Guidelines for The Sanitary Design and Fabrication of Dairy 

Processing Equipment (2001)