An Equal Opportunity Provider and Employer

Agricultural

Marketing

Service

Federal Grain Inspection 

Service

Field Management 

Division 

1400 Independence Ave. 

SW, Stop 3630

Washington, D.C. 20250

Voice (202) 720-0228

Fax (202) 690-3951

Hotline 1-800-998-3447

Reference #238 May 5, 2011

TO: FGIS POLICY BULLETIN BOARD

FROM: Samantha Simon, Deputy Director

 Field Management Division 

SUBJECT: Unit Train Inspection Options

ORIGINATING OFFICE: Policies, Procedures, and Market Analysis Branch

1. PURPOSE

This memorandum clarifies the policy on inspection options for unit 

trains.

2. BACKGROUND

The variety of load orders presented to the official inspection system 

for unit train loading has grown recently. The applicant can choose 

to have each car graded as an individual lot, load the unit train using 

the CuSum plan, use composite sample analysis, or use average 

composite analysis to achieve the desired quality. Combined lot

procedures can be used to further combine multiple carriers on a 

single certificate. If the applicant requests multiple railcars on a single 

certificate, the applicant has several options for certification.

3. POLICY

a. Individual Lot.

(1) Inspection. When inspecting each rail car on an individual basis

each rail car will represent one lot and a certificate will be issued 

for each car.

(2) Review Inspection.

Applicants may request review inspections (reinspection, appeal

inspection, or Board appeal inspection) for each lot.
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(3) Combined Lot.

When the inspection of all rail cars has been completed, the 

applicant has the option of requesting combined lot procedures 

for certifying multiple carriers of similar grade on a single 

certificate (see Code of Federal Regulations (CFR) 800.85). For 

example, if the first, third, and fifth car all grade #2 Yellow Corn, 

these railcars can be combined on one certificate.

b. CuSum.

(1) Inspection.

Performing grain inspections under Uniform Shiplot and 

Combined Lot Inspection Plan, commonly known as the CuSum 

plan is also an option when loading a unit train (Grain Inspection 

Handbook, Book III, Chapter 1 Inspection of Shiplots, Unit 

Trains and Lash Barges and CFR 800.86). CuSum represents 

an online acceptance sampling plan that provides continuous 

quality information with the objective of obtaining a consistent 

quality throughout the lot. This is achieved by using

statistically based tolerances.

Under CuSum each railcar is considered a component when 

multiple cars are combined to form a sublot. Component samples 

are combined to form a sublot sample, which may represent as 

much as 10 cars in a unit train if certain conditions are met. Unit 

train components are combined in the order they are sampled if 

order can be determined. Each component sample is analyzed 

for odor, insects and condition to determine whether any factor 

exceeds the limits for the declared grade by more than one 

numerical grade. If a component sample result exceeds the 

grade limit by more than one numerical grade (does not apply to 

nonnumeric grading factors, such as dockage, subclass, protein, 

oil, etc.) or contains a condition not included in the load order, 

the grain in that component is declared a “material portion”. The 

applicant will then have an option to either remove the material 

portion from the lot, or leave the material portion on board and 

request a separate certificate. The component samples not 

designated as a “material portion” are then combined with

other uniform component samples to form a sublot.
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Each sublot sample is analyzed for all factors and criteria in 

accordance with the Official U.S. Standards for Grain and the 

sales contract. The sublot is designated a “material portion” if 

any factor exceeds allowable CuSum breakpoints or the load 

order limits, exceeds FDA defect action levels, or meets U.S. 

Sample Grade criteria for other factors. Once a sublot is formed 

it cannot be reassembled to avoid exceeding the allowable 

breakpoints or to avoid declaring the sublot U.S. Sample 

Grade.

Grain conforming to CuSum requirements is certified as a single 

lot based on the combined average of the sublot results.

(2) Review Inspections.

Applicants may request review inspections of material portions

(components or sublots) or of the entire lot.

(3) Average Quality.

(a) Inspection.

Average quality is part of the CuSum loading plan and 

adheres to the basic CuSum rules, (e.g. combining 

acceptable component samples in the order that sampling 

was completed to form a sublot etc.). Average quality 

pertains to factors that are grade determining, and some 

non-grade determining such as moisture content. When 

“average quality certification” is requested on the load order, 

average quality will not apply to class (except for grain 

where class is a grading factor), subclass, special grade 

factors, sample grade factors, or aflatoxin. CuSum rules 

must be applied.

(b) Components.

Component samples must meet the type of grain definition 

for the contracted grain (e.g. corn, soybeans, wheat, etc.). 

Component samples not meeting the type of grain definition 

for the contracted grain or identified as Sample Grade, 

because they meet or exceed the Sample Grade limits for 

that particular type of grain, will be designated as material 

portions.
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(c) Sublots.

Sublot results are averaged to arrive at the final grade. 

Material portions occur when CuSum or absolute limits are 

exceeded for type of grain, class or subclass factors, or 

when a sample exceeds limits for Sample Grade factors. 

Material portions cannot occur when a sublot exceeds self 

imposed limits for a particular factor. For example, the load 

order specifies #2 or better Yellow Corn, average quality 

all factors, maximum 12.0 percent DKT. Since 12.0 percent 

DKT is outside the parameters for #2 Yellow Corn,

the limit of 12.0 percent is interpreted as a self imposed 

limit, not a CuSum factor. A sublot result of 12.2 percent 

therefore would not be a material portion, as it only exceeds 

a self imposed limit. Thus, a review inspection cannot be 

obtained on a self imposed limit violation.

(d) Review Inspections.

Only sublots that are out of condition, have an odor, exceed 

class requirements under cusum when applicable, or are 

sample grade can be designated as material portions. 

Sublots/components that are not material portions cannot 

be reviewed individually, however, the applicant can request 

review inspection of entire lots.

c. Composite.

(1) Inspection.

The applicant can request official personnel to combine or 

composite samples from a maximum of five railcars into one 

sample for analysis for certification called Composite Sample 

Analysis. Unlike the CuSum plan, it is not necessary to sample 

the carriers comprising the requested composite sample in the 

order they were loaded.
Page 5

To form a composite sample from multiple railcars, official 

personnel must sample each individual railcar (component) and 

examine the component for odor, insects, and condition. All of 

the rail cars that are combined must be uniform with respect to 

condition (i.e., infestation, odor, sample grade factors, special 

grades) and must meet class requirements. Components 

representing railcars that contain grain that has an odor, or is out 

of condition, may not be joined with samples of good quality to 

form a composite sample. Components representing individual

carriers that contain insects, but are not “infested” by definition 

in the U.S. Standards for Grain, may be composited with other 

samples that are “OK” for odor and condition to form a composite 

sample of the lot. For individual carriers that meet the definition 

of “infested”, the shipper has the options listed in Directive 

9180.59 “Composite Analysis for Combined Land Carrier 

Inspections”.

The official service provider cannot grade and certify the 

individual cars prior to the applicant selecting which carriers to 

combine for the composite. However, the applicant can request 

submitted sample analysis or official commercial inspection 

service (OCIS) analysis of the railcars (components) prior to 

designating the cars selected for a composite.

Once the composite is formed, the composite group may 

not be reassembled into different combinations to meet the 

desired quality.

(2) Review Inspection.

The applicant may request review (reinspection, appeal, board 

appeal) inspections on the composite sample. The basis of the 

inspection is the file sample of the composite.

(3) Combined Lot.

When complete inspection of all composites has been 

finished, the applicant has the option of requesting combined 

lot procedures for certifying multiple composites on a single 

certificate (see Code of Federal Regulations 800.85). For 

example if the first, third, and fifth composites are #2 Yellow 

Corn, these composites (of like quality) may be combined

on a single certificate.
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d. Average Composite.

(1) Inspection.

To form an average composite sample from multiple railcars, 

official personnel must sample each individual railcar, examine 

the component for odor, insects, and condition, and grade each 

component individually (with no certificates issued). After grading 

individual components, the applicant may select the components 

to be combined for the average composite grade. The 

components have to be similar in condition but do not have to be 

of the same grade. However, all of the components must be of 

the same class. Component samples which exceed FDA defect 

action levels or are identified as sample grade based on sample 

grade criteria may not be combined for the average composite 

grade. Each average composite may contain a maximum of five 

railcars and each railcar represents a component.

Once an average composite is formed it may not be 

reassembled.

(2) Reinspection.

After an average composite is formed, a review inspection can be

performed but must be on the same basis as the original 

inspection. Since cars/components were graded individually then 

averaged, the review inspection will be on the basis of a review of 

each carrier. For example, cars/components 1, 8, 12, 20, and 25 

were graded individually then averaged to form a single grade, 

thus the review inspection would be on the basis of a review of 

each car, then averaged. Appeal and board appeal

inspections follow the same logic.

(3) Combined Lot.

When complete inspection of all composites has been 

finished, the applicant has the option of requesting combined 

lot procedures for certifying multiple composites on a single 

certificate (see Code of Federal Regulations 800.85). For 

example if the first, third, and fifth composites are #2 Yellow Corn, 

these composites (of like quality) may be combined on a single 

certificate.
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4. QUESTIONS 

Direct any questions concerning this policy

AMS - FGIS Policies Procedures Market Analysis Branch.