Guidance for Industry 
 
Pre-Storage Leukocyte Reduction of Whole 
Blood and Blood Components Intended for 
Transfusion 
 
 
 
 
 
 
 
 
 
Additional copies of this guidance are available from the Office of Communication, Outreach and Development (OCOD), 
(HFM-40), 1401 Rockville Pike, Suite 200N, Rockville, MD 20852-1448, or by calling 1-800-835-4709 or 301-827-1800, 
or e-mail ocod@fda.hhs.gov, or from the Internet at http://www.fda.gov/BiologicsBloodVaccines/
GuidanceComplianceRegulatoryInformation/Guidances/default.htm. 
 
For questions on the content of this guidance, contact OCOD at the phone numbers or e-mail address listed above.  
 
 
 
 
 
 
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Biologics Evaluation and Research 
September 2012
    Contains Nonbinding Recommendations 
 
TABLE OF CONTENTS  
 
I.  INTRODUCTION.............................................................................................................1 
II.  BACKGROUND...............................................................................................................2 
A.  Changes from FDA Memorandum, Recommendations and Licensure 
Requirements for Leukocyte-Reduced Blood Products, May 29, 1996.........2 
B.  Established Benefits of Pre-Storage Leukocyte Reduction...............................3 
C.  Potential Benefits of Pre-Storage Leukocyte Reduction...................................3 
D.  Safety Concerns Related to Bedside Leukocyte Reduction Filtration.............4 
E.  Definitions..............................................................................................................4 
III.  VALIDATION OF THE LEUKOCYTE REDUCTION PROCESS...........................5 
A.  Methods of Leukocyte Reduction........................................................................6 
B.  Equipment Installation Qualification.................................................................6 
C.  Validation Protocol Development........................................................................6 
D.  Process Performance Qualification (Operator).................................................7 
E.  Product Performance Qualification for the Leukocyte Reduction Process....7 
F.  Leukocyte Reduction Performance Qualification Criteria...............................8 
G.  Investigation of Product Performance Qualification Failure.........................10 
H.  Re-Qualification/Re-Validation.........................................................................10 
IV.  QUALITY ASSURANCE AND MONITORING........................................................10 
A.  Component Testing.............................................................................................11 
B.  Equipment/Ancillary Supplies...........................................................................12 
C.  Operator Training..............................................................................................12 
D.  Standard Operating Procedures........................................................................13 
1.  Requirements for Standard Operating Procedures (SOPs)...................................13 
2.  Additional Requirements and Recommendations to be included in SOPs...........13 
V.  LABELING.....................................................................................................................14 
VI.  REPORTING CHANGES TO AN APPROVED BIOLOGICS LICENSE 
APPLICATION (BLA)...................................................................................................15 
A.  Prior Approval Supplement (PAS):  Changes Requiring Supplement 
Submission and Approval Prior to Distribution of the Product Made Using 
the Change (Major Changes) (21 CFR 601.12(b))...........................................15 
B.  Changes Being Effected in 30 Days (CBE-30) Supplement: Changes 
Requiring Supplement Submission at Least 30 Days Prior to Distribution of 
the Product Made Using the Change (21 CFR 601.12(c))...............................17 
C.  Changes to be Described in an Annual Report (Minor Changes) (21 CFR 
601.12(d)).............................................................................................................17 
D.  Submission of Documents...................................................................................17 
VII.  CONTACT INFORMATION........................................................................................20 
VIII.  REFERENCES................................................................................................................21 
APPENDIX..................................................................................................................................24 
i    Contains Nonbinding Recommendations 
 
Guidance for Industry 
 
Pre-Storage Leukocyte Reduction of Whole Blood and Blood 
Components Intended for Transfusion 
 
 
This guidance represents the Food and Drug Administrations (FDAs) current thinking on this 
topic.  It does not create or confer any rights for or on any person and does not operate to bind 
FDA or the public.  You can use an alternative approach if the approach satisfies the 
requirements of the applicable statutes and regulations.  If you want to discuss an alternative 
approach, contact the appropriate FDA staff.  If you cannot identify the appropriate FDA staff, 
call the appropriate number listed on the title page of this guidance. 
 
 
I.  INTRODUCTION  
 
We, FDA, are issuing this guidance document to provide you, blood establishments, with 
recommendations for pre-storage leukocyte reduction of Whole Blood and blood components 
intended for transfusion, including recommendations for validation and quality control 
monitoring of the leukocyte reduction process.  We also provide information to licensed blood 
establishments for submitting biologics license application supplements to include leukocytes 
reduced components.  This guidance applies to Whole Blood, Red Blood Cells, Plasma, and 
Platelets1 manufactured from Whole Blood or collected by automated methods2.  This guidance 
document finalizes the draft guidance of the same title dated January 2011 and supersedes the 
FDA memorandum issued on May 29, 1996, entitled Recommendations and Licensure 
Requirements for Leukocyte-Reduced Blood Products. 
 
We support the use of leukocytes reduced blood and blood components for specific indications 
(see section II.B) and seek to streamline the licensing procedure for leukocytes reduced blood 
components to assist blood establishments in making pre-storage leukocytes reduced blood 
components more widely available.    
 
Although there have been reports of adverse events associated with leukocyte reduction by 
filtration (Refs. 1 and 2), advances in blood cell separation technology generally enable the safe 
reduction of leukocytes.  We believe that increased availability of pre-storage leukocytes reduced 
blood components for non-targeted recipients will support the treatment of recipients who may 
                                                 
1 The guidance document entitled Guidance for Industry and FDA Review Staff:  Collection of Platelets by 
Automated Methods dated December 2007 contains our recommendations for validating; quality assurance and 
monitoring; labeling and licensure for leukocyte reduction of Platelet, Pheresis products.  
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/Guidances/Blood/ucm07
3382.htm. 
2 The guidance document entitled Guidance for Industry:  Recommendations for Collecting Red Blood Cells by 
Automated Apheresis Methods Technical Correction dated February 2001.  
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/Guidances/Blood/ucm07
6756.htm. 
1    Contains Nonbinding Recommendations 
 
benefit from receiving leukocytes reduced components but have not been identified as falling 
within the indications identified in section II.B.  We suggest that consideration should be given 
to making leukocytes reduced blood components more widely available.  
 
FDAs guidance documents, including this guidance, do not establish legally enforceable 
responsibilities.  Instead, guidances describe the FDAs current thinking on a topic and should be 
viewed only as recommendations, unless specific regulatory or statutory requirements are cited.  
The use of the word should in FDAs guidances means that something is suggested or 
recommended, but not required.  
 
 
II.  BACKGROUND 
 
A.  Changes from FDA Memorandum, Recommendations and Licensure 
Requirements for Leukocyte-Reduced Blood Products, May 29, 1996  
 
In a May 29, 1996 memorandum, we issued recommendations on leukocyte reduction, a 
manufacturing step performed under controlled and monitored laboratory conditions.  
Under those recommendations, leukocytes reduced components were to contain < 5.0 x 
106 residual white blood cells (WBCs) per each Whole Blood, Red Blood Cells or 
Platelets, Pheresis collection, and < 8.3 x 105 residual WBCs per each Platelets derived 
from Whole Blood, with at least an 85 percent recovery of the original component.  The 
memorandum was consistent with the outcome of a public workshop held in March 1995 
on leukocytes reduced products.  This guidance document maintains those standards for 
residual WBCs and modifies the 1996 recommendations as follows: 
 
1.  Statistical methods for validation and quality control monitoring of the 
leukocyte reduction process are provided.  Consideration is now given to the 
distinction between process and non-process failures.  
 
2.  This document discusses certain donor specific traits which may affect 
leukocyte reduction processes.  Observations have identified a number of 
donor-specific factors (such as abnormal polymerization of hemoglobin S 
(HbS)) during the filtration process (Refs. 3 through 7) that may result in filter 
blockage or inadequate leukocyte reduction.  The identification of sickle cell 
trait or other factors associated with incomplete filtration for a given donor is 
an important adjunct to overall process control.  We encourage blood 
establishments to reduce component loss by identifying donors whose blood 
fails to filter successfully and to divert subsequent donations from such donors 
for uses other than leukocytes reduced transfusable Whole Blood and blood 
components.  Testing of donors for HbS may be appropriate. 
 
3.  We are also providing an option for supplemental labeling of blood 
components (not applicable to Whole Blood derived Platelets) when the 
residual WBC count of an individual component has been determined by 
direct count to be < 1.0 x 106.  A supplemental label in the form of a tie-tag 
may be affixed to the container stating:  The residual white blood cell count 
2    Contains Nonbinding Recommendations 
 
of this component has been determined to be < 1.0 x 106.  We make this 
recommendation in response to comments requesting more specific labeling 
for leukocytes reduced products with a lower WBC count. 
 
4.  We recommend that Red Blood Cell recovery should be calculated by 
comparison of the post-filtration to pre-filtration volume x hematocrit, weight 
x hematocrit, or weight unless otherwise instructed in the manufacturers 
direction for use. 
 
B.  Established Benefits of Pre-Storage Leukocyte Reduction 
 
Leukocytes reduced Whole Blood and blood components have been shown to reduce the 
following: 
 
  recurrent febrile, non-hemolytic transfusion reaction (i.e., patients with a history 
of two or more febrile reactions to transfusion) (Refs. 8 through 12); 
  alloimmunization to leukocyte antigens that may complicate care of patients who 
undergo transplantation or chronic transfusion therapy (e.g., patients with aplastic 
anemia or hematologic malignancies); and 
  transmission of cytomegalovirus (CMV) to patients at increased risk of CMV 
disease (e.g., chemotherapy recipients for whom severe neutropenia is expected, 
recipients of hematopoietic progenitor cell replacement therapy, CMV 
seronegative recipients of CMV seronegative solid organ grafts, and low birth 
weight premature infants) (Ref. 13).   
 
We believe it is advantageous to provide leukocytes reduced components to reduce such 
adverse events.  In addition, we believe it is advantageous to provide pre-storage 
leukocytes reduced components in preference to bedside filtered blood components based 
on quality and safety considerations (Ref. 14).  Routine use of leukocytes reduced blood 
components further protects patients who have increased risk, but whose conditions have 
not yet been identified. 
 
C.  Potential Benefits of Pre-Storage Leukocyte Reduction   
 
Potential, but not established, benefits of leukocyte reduction include reduction of:  
 
  transfusion-associated immunomodulation (Ref. 15); 
  bacterial overgrowth (Refs. 8 and 16); 
  viral reactivation (Refs. 8 and 16); 
  reperfusion injury following cardiopulmonary bypass (Ref. 16); 
  red blood cell and platelet storage lesions (Ref. 17); 
  transfusion-transmitted Leishmania infection (Ref. 18); and 
  transfusion-transmitted variant Creutzfeldt-Jakob disease (vCJD) (Ref. 19). 
 
Limited scientific data have suggested the possibility that leukocyte reduction may be a 
useful measure against the risk of transfusion-transmitted vCJD (Refs. 19 through 23).  
3    Contains Nonbinding Recommendations 
 
Some international blood authorities have implemented or are considering the 
implementation of a regulatory requirement to leukocyte reduce all Red Blood Cells and 
Platelets intended for transfusion (universal leukocyte reduction), as well as plasma for 
further manufacturing to reduce the risk of vCJD transmission.  
 
Similarly, the potential to reduce infection by pathogens that are primarily WBC 
associated may extend beyond CMV (Refs. 11 and 12) to include other known and 
unknown agents potentially transmitted by WBCs (Ref. 19). 
 
Leukocyte reduction is not considered appropriate for the prevention of transfusion-
associated graft-versus-host disease.  At this time, irradiation of blood products is the 
only definitive method available to prevent this serious and often fatal transfusion 
outcome in patients at risk (Ref. 24). 
 
D.  Safety Concerns Related to Bedside Leukocyte Reduction Filtration 
 
Bedside filtration remains available as a leukocyte reduction method to physicians 
prescribing transfusion therapy.  As a post-storage procedure, however, bedside filtration 
has been associated with precipitous hypotension in the transfusion recipient, an 
infrequent yet serious adverse effect not associated with pre-storage leukocyte reduction 
(Ref. 25).  Patients on medications that inhibit the angiotensin converting enzyme (ACE 
inhibitors) appear to be particularly susceptible.  Pre-storage leukocyte reduction allows 
the leukocyte reduction process to be monitored under controlled conditions that assure 
component purity, consistency, and safety and is therefore generally preferable to bedside 
filtration (Refs. 25 through 27). 
 
E.  Definitions 
 
For the purposes of the terms used in this guidance, the following definitions apply: 
 
Automated Blood Cell Separator (ABCS):  A device that uses a centrifugal or filtration 
separation principle to automatically withdraw Whole Blood from a donor, separate the 
Whole Blood into blood components, collect one or more of the blood components and 
return to the donor the remainder of the Whole Blood and blood components.  The ABCS 
device is intended for routine collection of blood and blood components for transfusion 
or further manufacturing use.  
 
Non-process failure:  Failure of a leukocyte reduction process due to a non-controllable 
parameter (i.e., donor specific characteristic such as HbS).  Note:  In your sampling plan 
for validation or quality control (QC) testing, you may exclude (and replace) non-process 
failures.   
 
Percent recovery (of the original component):  Ratio of the post-filtration to the pre-
filtration content of the component expressed as a percent. 
 
4    Contains Nonbinding Recommendations 
 
  Red Blood Cells/Whole Blood:  Red Blood Cell percent recovery of the original 
component can be determined by comparing the pre-filtration content to the post-
filtration content by using any of the following methods:   
o  volume x hematocrit;  
o  weight x hematocrit; 
o  weight:  The weight method should be used in conjunction with a 
documented visual check to ensure that abnormal red blood cell 
retention has not occurred; or 
o  as described by the manufacturer in the package insert. 
 
  Platelets:  Because of selective removal of platelets by leukocyte reduction 
filters, the percent recovery is to be determined by comparing the platelet yield 
pre-filtration to the platelet yield post-filtration (i.e., not by weight).  
 
Process failure:  Failure of a leukocyte reduction process due to an error that was 
avoidable if proper procedures, precautions and/or instructions were followed (i.e., not 
following manufacturers directions) or a product/device defect. 
 
Process validation:  In brief, is the collection and evaluation of data from the process 
design stage through production.  This validation establishes scientific evidence that a 
process is capable of consistently delivering quality product (Ref. 28). 
 
Residual White Blood Cell (WBC) content:  The number of WBCs remaining in a 
leukocytes reduced component, calculated by multiplying the WBC count from a sample 
of the component times the volume of the component. 
 
Yield:  The quantity that is actually produced during manufacturing. 
 
 
III.  VALIDATION OF THE LEUKOCYTE REDUCTION PROCESS 
 
The Current Good Manufacturing Practices (cGMP) regulations described in 21 CFR Parts 210 
and 211 contain the minimum requirements for methods to be used in, and the facilities or 
controls to be used for, the manufacture, processing, packing or holding of a drug to assure that 
the drug meets the safety requirements of the Federal Food, Drug, and Cosmetic Act, and has the 
identity and strength and meets the quality and purity characteristics that it purports or is 
represented to possess (21 CFR 210.1(a)).  These cGMP regulations apply to Whole Blood and 
blood components (21 CFR 210.2(a) and 211.1(b)) and supplement the cGMP regulations for 
blood and blood components contained in 21 CFR Part 606.  As an element of cGMP, process 
validation establishes scientific evidence that a process is capable of consistently delivering 
quality product3 (Ref. 28).  We recommend that establishing documentation of process 
validation include, but not be limited to, equipment installation qualification, validation protocol 
development, process operator performance qualification and product performance qualification 
(Ref. 28).  
 
                                                 
3 The requirement for process control is set forth in general terms in 21 CFR 211.100. 
5    Contains Nonbinding Recommendations 
 
A.  Methods of Leukocyte Reduction 
 
Whole Blood and blood components (including components collected by automated 
methods) intended for transfusion may be leukocyte reduced using any of the closed 
system or functionally closed methods as follows: 
  
  filtration through an in-line filter integral to the blood collection set or apheresis 
set with or without automated filtration (e.g., press through filtration) 
  filtration through a filter system attached to a blood component container using an 
FDA cleared sterile tubing connecting device (STCD) (Ref. 29) 
  direct, in-process leukocyte reduction for certain plateletpheresis and 
plasmapheresis collections (i.e., by ABCS devices). 
 
B.  Equipment Installation Qualification  
 
Section 606.60(a) (21 CFR 606.60(a)) requires that equipment be observed, standardized 
and calibrated on a regularly scheduled basis as prescribed in the Standard Operating 
Procedures Manual and must perform in the manner for which it was designed.  Upon 
initiation of an automated leukocyte reduction method, we recommend that the 
equipment used for leukocyte reduction (e.g., leukocyte reduction filter, ABCS device) 
be qualified as described in the operators manual or manufacturers directions for use. 
 
C.  Validation Protocol Development 
 
An integral element of the performance and documentation of process validation is the 
development of a validation protocol.  You should refer to FDAs Guidance for 
Industry:  Process Validation:  General Principles and Practices (Ref. 28) as an outline 
for developing your validation protocol.  We recommend that the validation protocol 
include, but may not be limited to: 
 
  a description of the leukocyte reduction method, including the device, to be used   
  acceptable values for the residual WBC count, including: 
o  residual WBC count post leukocyte reduction for the component (Whole 
Blood, Red Blood Cells, Platelets, Plasma) 
o  percent recovery of the original component for Whole Blood, Red Blood 
Cells, or Platelets when leukocytes are reduced by filtration or per the 
manufacturers specifications, if different 
  manufacturers specifications for processing parameters (if given)  
  failure investigation criteria 
  personnel training criteria 
  standard operating procedures (SOPs) for performing each element of the 
collection and manufacturing process  
  documentation of the validation protocol criteria for all of the above. 
 
6    Contains Nonbinding Recommendations 
 
D.  Process Performance Qualification (Operator) 
 
Each person engaged in the manufacture of leukocytes reduced components must have 
adequate education, training, or experience to assure their competent use of the devices 
involved (21 CFR 606.20(b)).  
 
We recommend that personnel training include the successful consecutive performance, 
under supervision, of an appropriate number of procedures, as defined by your facility.  
These procedures should result in leukocytes reduced components meeting the 
specifications for the specific leukocyte reduction methodology being qualified.  
 
E.  Product Performance Qualification for the Leukocyte Reduction Process 
 
Various factors may adversely influence the leukocyte reduction process, e.g., donor 
specific factors or improper use of an ABCS device.  The objective of product 
performance qualification is to verify that the leukocyte reduction method conforms to 
the claims of the device manufacturer and the blood establishment.  In addition, 
appropriate testing will establish confidence that the final component meets all release 
requirements for safety, purity, and potency (Refs. 28 through 31).  All components 
collected during the qualification process can be released for transfusion provided that 
they meet minimum specifications as defined by the device manufacturer, are labeled 
appropriately, and are otherwise suitable. 
 
We believe that, generally, product performance qualification only needs to be performed 
when the leukocyte reduction method (either by ABCS devices or filtration) is first put 
into use at an establishment.  We note the following: 
 
  For establishments using a single model ABCS device from only one 
manufacturer, all instruments available for use with that ABCS device should be 
included in the initial product performance qualification.  
  For establishments using multiple models of ABCS devices from one or more 
manufacturers you should conduct full product performance qualification for each 
device type on all instruments available for use with that ABCS device type.  
  For establishments using leukocyte reduction filters from different manufacturers, 
or when there is a change to a different filter manufacturer, you should conduct 
full product performance qualification for each filter type from each 
manufacturer. 
 
Product performance qualification should include testing for the residual WBC count and 
percent recovery of the original component as recommended in section III.C, and testing 
of components processed by all trained operators.  In addition, we recommend you 
perform residual WBC count testing within 48 hours of collection (Ref. 33) or per the 
manufacturers directions for the cell counting methodology. 
 
You must conduct an investigation of each product performance qualification failure, and 
when appropriate, initiate corrective action and follow-up measures (21 CFR 211.192 and 
606.100(c)).  There should be ongoing assurance that the process continues to perform at 
7    Contains Nonbinding Recommendations 
 
the level established during the product performance qualification.  Evaluating the 
performance of the process identifies problems and determines whether action must be 
taken to correct, anticipate, and prevent problems (21 CFR 211.180(e), 211.192, and 
606.100(c)).  We understand that some failures may occur due to conditions not resulting 
from a failure of the process (e.g., failure due to donor specific characteristic such as 
HbS). 
 
F.  Leukocyte Reduction Performance Qualification Criteria 
 
Conformance to product standards must be assessed by a statistically valid method (see 
21 CFR 211.160(b)).  In the absence of a validation method (plan) provided by the 
manufacturer, you should develop a statistically valid plan based on 95% confidence that 
more than 95% of the components will meet the recommended results.  One possible 
approach to process validation is a two-stage sampling plan based upon the binomial 
distribution.  In this approach, an initial representative sample of components with a pre-
determined sample size should be tested consecutively (validation) or randomly (QC 
monitoring).  Identified non-process failures may be excluded from the sample size and 
replaced.  Conformance can be demonstrated if an acceptable number of process failures 
are observed in this sample.  In the event that there is one more process failure than 
permitted in the initial sample, a second sample of components may be tested 
consecutively.  Conformance can be demonstrated if no further process failures are 
observed in the second sample.  The size of the second sample will depend on the size of 
the first sample.  We provide two examples to illustrate the use of this approach:   
 
Example 1:  The first stage sample is 60 consecutive collections.  If no process 
failures are observed among these 60 components, conformance has been 
demonstrated and no further testing is required.  If one process failure is observed 
among the 60 components, a second sample of 71 consecutive collections may be 
tested.  If no further process failures are observed among these 71 components, 
conformance has been demonstrated and no further testing is required.  If more than 
one process failure is observed among the first sample of 60 components, or if one or 
more additional process failures are observed among the second sample of 71 
components, the validation has failed and no additional testing is recommended to 
qualify the process.  A failure investigation should be undertaken.  (See section 
III.G.) 
 
Example 2:  The first stage sample is 94 consecutive collections.  If zero or one 
process failures are observed among these 94 components, conformance has been 
demonstrated and no further testing is required.  If two process failures are observed 
among the 94 components, a second sample of 75 consecutive collections may be 
tested.  If no further process failures are observed among these 75 components, 
conformance has been demonstrated and no further testing is required.  If more than 
two process failures are observed among the first sample of 94 components, or if one 
or more additional process failures are observed among the second sample of 75 
components, the validation has failed and no additional testing is recommended to 
qualify the process.  A failure investigation should be undertaken.  (See section 
III.G.) 
8    Contains Nonbinding Recommendations 
 
 
Note that the sample sizes are pre-determined and fixed based on the required statistical 
criteria.  For example, if you plan to test 94 samples and encounter no failure in the first 
60 samples, changing your plan to 60 samples is not permitted.   
 
In some cases, you may decide on a one-stage sampling strategy rather than the two-stage 
strategy described above.  Based on the binomial distribution, conformance can be 
demonstrated by observing zero process failures in a fixed sample of 60 components, one 
or fewer failures in a fixed sample of 94 components, or two or fewer failures in a fixed 
sample of 124 components.    
 
We recommend that the following parameters as listed in Table 1 should be assessed to 
assure an overall statistically-based level of product conformance: 
 
  residual WBC content   
  percent recovery of the original component OR per the manufacturers 
specifications. 
 
Table 1:  Leukocyte Reduction (LR) Performance Qualification Criteria for Blood 
and Blood Components (other than Platelets, Pheresis4) 
 
Blood Component  Recommended  Recommended Minimum Post-Filtration 
Residual WBC 
Content 
Whole Blood, LR  < 5.0 x 106*   85% recovery*** of original RBC content  
Red Blood Cells, LR  < 5.0 x 106*  85% recovery*** of original RBC content 
Plasma Products that  < 5.0 x 106*  N/A 
are LR 
Platelets, LR**  < 8.3 x 105 per  85% recovery*** of original platelet yield; 
individual (i.e.,  and a minimum of  
unpooled) unit  > 5.5 x 1010 platelets for 75% of units 
*Per component. 
**Multiple units of Platelets are often pooled after storage and prior to filtration, rather than filtered 
individually prior to storage and pooling.  In this instance, the pooled and then filtered product for 
transfusion should contain 5.0 x 106 residual WBCs.  For example, multiple units of Platelets (4-6 units) 
are pooled into a single platelet dose.  The total (4-6 units) should contain 5.0 x 106 residual leukocytes.  
The same recommendation for 5.0 x 106 residual WBCs applies if platelet units are pooled before storage, 
whether filtered before or after storage. 
***Or per the device manufacturers specifications, if different. 
 
Plasma components, when manufactured under cGMP, may inherently have a residual 
WBC content of < 5.0 x 106 per unit.  Currently accepted and validated cell counting 
procedures may need to be modified for plasma components.  Plasma components 
(including Fresh Frozen Plasma and Cryoprecipitated Antihemophilic Factor) may be 
                                                 
4 See footnote 1. 
9    Contains Nonbinding Recommendations 
 
labeled Leukocytes-Reduced provided that manufacturing process validation as 
described in this section (section III) includes these components and the ABCS device is 
cleared to manufacture the product.  
 
G.  Investigation of Product Performance Qualification Failure 
 
Section 211.192 (21 CFR 211.192) requires that the failure of a batch or any of its 
components to meet any of its specifications be thoroughly investigated.  If a post-
filtration residual WBC count is > 5 x 106 (> 8.3 x 105 for unpooled Platelets) and/or fails 
to meet the percent recovery of the original component during validation, you must 
conduct an investigation of the product performance qualification failure  
(21 CFR 211.192 and 606.100(c)). 
 
You must investigate collections that fail to meet the percent Red Blood Cell recovery or 
Platelet recovery criteria (21 CFR 211.192 and 606.100(c)).  However, the component 
may be released if the actual platelet yield or Red Blood Cell volume is determined to be 
suitable by the quality control unit and the component is labeled appropriately. 
 
Product performance qualification failures may occur due to conditions not resulting 
from a failure of the process.  For example, if the observed failure is investigated and 
found to be due to a donor-specific factor, it does not constitute a process failure and 
should be excluded from the performance qualification evaluation.  
 
When a failure during product performance qualification is investigated and found to be 
due to an identified donor-specific factor, we encourage you to flag the donor record.  
Upon a subsequent occurrence of incomplete filtration or inadequate WBC removal, we 
encourage you to consider not using this donor for future donations of leukocytes reduced 
components.  
 
H.  Re-Qualification/Re-Validation 
 
  Exceeding the allowable process failures of the product performance 
qualification may indicate that the process is not in control.  You must 
investigate and take appropriate follow-up action on the source of this failure  
(21 CFR 211.192 and 606.100(c)) and should repeat validation. 
  The manufacturer may provide re-qualification requirements for the device used 
in the leukocyte reduction process. 
 
 
IV.  QUALITY ASSURANCE AND MONITORING  
 
Quality assurance (QA) is the sum of activities planned and performed to provide confidence that 
all systems and system elements that influence the quality of the component are functioning as 
expected (Ref. 30).  When this is demonstrated, the process is considered to be in a state of 
control.  The determination of whether a process is operating in a state of control is made by 
analyzing the day-to-day process, performance variability and the data for conformance with the  
10    Contains Nonbinding Recommendations 
 
manufacturers specifications.  Please refer to FDAs Guideline for Quality Assurance in Blood 
Establishments (Ref. 30) for assistance in developing a QA and monitoring program.  This 
program is distinct from the initial validation described in section III. 
 
You must have a QC unit that has the responsibility and authority to approve or reject all 
components, containers, closures, in-process materials, packing materials, labeling and drug 
products and the authority to review production records to assure that no errors have occurred or, 
if errors have occurred, that they have been fully investigated (21 CFR 211.22(a)).  Thus, the QC 
units responsibilities include the review of production records, and the review of complaints 
involving the possible failure of a product to meet its specifications (See, for example,  
21 CFR 211.22, 211.192, 211.198, and 606.100(c)).  In addition, your laboratory control 
procedures must include adequate provisions for monitoring the reliability, accuracy, precision 
and performance of laboratory test procedures and instruments (21 CFR 606.140(b)). 
 
A.  Component Testing 
 
A QA program should include in-process monitoring of the manufacturing procedures 
and QC testing (Ref. 16). 
 
Under 21 CFR 211.160(b), laboratory controls must include the establishment of 
scientifically sound and appropriate specifications, standards, sampling plans and test 
procedures.  We will consider statistical plans that confirm a < 5% non-conformance rate 
with 95% confidence.  
 
One example of a scientifically sound statistical sampling and analytic plan is based on a 
two-stage binomial approach.  The sampling sizes described in section III.F will confirm 
with 95% confidence a < 5% non-conformance rate for residual WBC counts.  Another 
example of a scientifically sound plan is based on the hypergeometric distribution (see 
Appendix).  The hypergeometric plan is only for quality control sampling plans and 
cannot be used for validation.  Other statistical plans may also be appropriate, such as 
the use of scan statistics (Ref. 32) or a lower confidence limit (e.g., for platelet yields we 
will consider statistical plans that confirm a < 5% non-conformance rate with 75% 
confidence). 
 
As part of your QC procedures, we recommend that you: 
 
  define a plan which representatively identifies collections to be tested for each 
component type (Whole Blood, Red Blood Cells, Platelets and Plasma) and 
ensures testing for each leukocyte reduced method (i.e., each filter type in use or 
each type of apheresis collection device) as detailed in Table 2; 
  test the component (Whole Blood, Red Blood Cells, Plasma, Platelets); 
  test for the residual WBC count within 48 hours after collection (Ref. 33), or per 
the manufacturers directions for the cell counting methodology; 
  test for percent recovery of the original component for Whole Blood, Red Blood 
Cells or Platelets or per manufacturers directions for use (e.g., minimum Red 
Blood Cell volume); 
11    Contains Nonbinding Recommendations 
 
  determine the volume of the collection/component on the day of QC testing, after 
removal of all samples; 
  define procedures for investigating failures during QC, including the criteria that 
will categorize a failure as either a process or non-process failure.  Incomplete 
filtration and post-filtration residual WBC counts in excess of the defined 
standards are to be considered as two distinct types of process failure. 
 
Table 2:  For blood and blood components (other than Platelets, Pheresis5), we 
recommend the following QC results to be acceptable: 
 
Blood Component  Residual WBC  Minimum Post-Filtration 
Content 
Whole Blood, LR  < 5.0 x 106*   85% recovery*** of original WB 
content   
Red Blood Cells, LR  < 5.0 x 106*  85% recovery*** of original RBC 
content 
Plasma Products, LR  < 5.0 x 106*  N/A 
Platelets, LR**  < 8.3 x 105 per  85% recovery*** of original platelet 
individual (i.e.,  yield; and a minimum of  
unpooled) unit  > 5.5 x 1010 platelets for 75% of units 
*Per component. 
**Multiple units of Platelets are often pooled after storage and prior to filtration, rather than filtered 
individually prior to storage and pooling.  In this instance, the pooled and then filtered product for 
transfusion should contain < 5.0 x 106 residual WBCs.  For example, for an adult transfusion recipient, 
multiple units of Platelets (4-6 units) are pooled into a single platelet dose.  The total (4-6 units) should 
contain < 5.0 x 106 residual WBCs.  The same recommendation for < 5.0 x 106 residual WBCs applies if 
platelet units are pooled before storage, whether filtered before or after storage. 
***Or per the device manufacturers specifications, if different. 
 
B.  Equipment/Ancillary Supplies  
 
Equipment must be observed, standardized, and calibrated on a regularly scheduled basis 
as prescribed in the Standard Operating Procedures Manual (21 CFR 606.60(a)).  Such 
equipment includes, but may not be limited to the ABCS, cell counting instrument(s), 
scales, blood shaker and STCD.  
 
Supplies and reagents must be used in a manner consistent with instructions provided by 
the manufacturer (21 CFR 606.65(e)).  In addition, all supplies (including filters) and 
reagents must meet all of the requirements described in 21 CFR 606.65. 
 
C.  Operator Training 
 
Operators must have adequate training, education, experience, or combination thereof, to 
assure competent performance of their assigned functions (21 CFR 606.20(b)).  Control 
                                                 
5 See footnote 1. 
12    Contains Nonbinding Recommendations 
 
over operational variables should be maintained through initial and continued staff 
training, routine staff participation in leukocyte reduction and periodic assessment of 
operator performance.  We recommend that assessment of operators include scheduled 
competency assessment and proficiency testing.  In addition, we recommend that you 
develop appropriate training on leukocyte reduction processes and procedures and/or 
equipment maintenance as updated information becomes available. 
 
D.  Standard Operating Procedures  
 
1.  Requirements for Standard Operating Procedures (SOPs) 
 
Equipment used for leukocyte reduction must perform in the manner for which it 
was designed (21 CFR 606.60(a)).  Supplies and reagents must be used in a 
manner consistent with the instructions provided by the manufacturer  
(21 CFR 606.65(e)).  Written SOPs must be maintained and must include all steps 
to be followed in the collection, processing, compatibility testing, storage, and 
distribution of blood and blood components (21 CFR 606.100(b)).  Therefore, you 
must have written SOPs for each step in the collection and processing of 
leukocytes reduced Whole Blood and blood components.   
 
2.  Additional Requirements and Recommendations to be included in SOPs 
 
  Sample handling:  Blood samples should be collected, processed, and 
tested within 48 hours (Ref. 33) (or per the manufacturers 
recommendations for the methodology) of leukocyte reduction.  The SOP 
should adequately describe sample storage temperature, time, mixing, etc.  
 
  Leukocyte reduction filters:  Leukocyte reduction filters are typically 
component-specific; a filter intended for one component type should not 
be used with other component types (Ref. 34).  Leukocyte reduction filters 
intended for bedside filtration should not be used for pre-storage leukocyte 
reduction. 
 
  Abnormal Red Blood Cell Retention:  Filtration steps should include 
instructions on how to identify excessive red blood cell retention in the red 
cell container and tubing above the filter.  
 
  Re-filtration:  Components that fail to leukocyte reduce appropriately 
should not be re-filtered, unless re-filtration is specified as appropriate by 
the device manufacturer in the instructions for use. 
 
  QC failures:  You must thoroughly investigate any unexplained 
discrepancy or the failure of a batch to meet any of its specifications  
(21 CFR 211.192).  You should define appropriate criteria for retesting of 
components, testing of additional components, final labeling, and 
disposition of components that fail to meet specifications.  For example: 
 
13    Contains Nonbinding Recommendations 
 
o  A blood component that requires a filtration time longer than the 
time interval specified in the manufacturers instructions for use 
may be released by the QA unit for transfusion as leukocytes 
reduced only if testing of that unit confirms acceptable component 
specifications and there is an investigation of the delayed filtration 
time.   
 
o  Leukocyte reduction by filtration can fail for Whole Blood and 
Red Blood Cells collected from donors with sickle cell trait (Refs. 
3 through 7 and Refs. 35 through 38) or other donor specific 
factors.  Tests for donor-specific factors may reduce the number of 
components lost to filter failures.  To address the investigation of 
filtration failures, the SOP may include testing the blood 
component for donor specific factors.  The blood unit associated 
with a filtration failure should not be released for transfusion as 
leukocytes reduced unless testing of that unit confirms acceptable 
component specifications. 
 
  Manufacturers performance specifications:  You should state the 
acceptable tolerance specifications for each leukocytes reduced blood 
component as described by the manufacturer.  You should have a 
procedure addressing the handling of components that do not meet the 
manufacturers performance specifications (e.g., use in research or further 
manufacture). 
 
  Labeling:  The general requirements for the labeling process are described 
in 21 CFR 606.120 and must be followed. 
 
 
V.  LABELING 
 
A circular of information must be available for distribution if the product is intended for 
transfusion (21 CFR 606.122). 
 
Your container labels must comply with 21 CFR 606.121 and 610.60.  The container label must 
include the proper name of the product, in a prominent position, with any appropriate modifier(s) 
and attributes (21 CFR 606.121(c)(1)).  One way to comply with the applicable labeling 
requirements is through of use of standard terminology.  For example, Table 3 lists the proper 
names of the major leukocytes reduced blood components, followed by the corresponding 
International Society of Blood Transfusion (ISBT) Code 128 name (Ref. 39).  The component 
labeling should include the phrase Leukocytes Reduced.  The phrases Leukocytes Removed, 
Leukocyte Poor, Leukocytes Depleted, and other similar terms should not be used in 
component labeling. 
 
Only those components meeting the recommended residual WBC content for leukocytes reduced 
blood components or prepared by a validated method known to meet the recommended residual 
14    Contains Nonbinding Recommendations 
 
leukocyte content for leukocytes reduced blood components may be labeled as Leukocytes 
Reduced. 
 
Those components (except Whole Blood derived Platelets) that have been tested and found to 
have a residual WBC count of < 1.0 x 106 may be labeled either with the actual residual 
leukocyte content via a supplemental label or a tie-tag stating:  The residual white blood cell 
count of this component has been determined to be < 1.0 x 106.   
 
Table 3:  Component Names for Container Labels 
 
Proper Name  ISBT 128 Name 
Whole Blood Leukocytes Reduced  WHOLE BLOOD LEUKOCYTES REDUCED 
RED BLOOD CELLS LEUKOCYTES 
REDUCED 
Red Blood Cells Leukocytes Reduced 
APHERESIS RED BLOOD CELLS 
LEUKOCYTES REDUCED 
Platelets Leukocytes Reduced  PLATELETS LEUKOCYTES REDUCED 
 
 
VI.  REPORTING CHANGES TO AN APPROVED BIOLOGICS LICENSE 
APPLICATION (BLA) 
 
An establishment that distributes leukocytes reduced blood components in interstate commerce 
must have an approved BLA, including an approval for leukocytes reduced blood components, in 
accordance with section 351 of the Public Health Service Act. 
 
Licensed establishments must report changes to their approved application(s) in accordance with 
21 CFR 601.12.  For assistance in reporting your changes see FDAs Guidance for Industry:  
Changes to an Approved Application:  Biological Products:  Human Blood and Blood 
Components Intended for Transfusion or for Further Manufacture dated July 2001.6  The 
information below is intended to assist you in determining which reporting mechanism is 
appropriate for a change to your approved BLA, as it applies to the manufacture of leukocytes  
reduced blood components.  You should prominently label each submission with the reporting 
category under which you are reporting your change, e.g., Prior Approval Supplement or 
Supplement - Changes Being Effected in 30 Days, or Annual Report.   
 
A.  Prior Approval Supplement (PAS):  Changes Requiring Supplement 
Submission and Approval Prior to Distribution of the Product Made Using 
the Change (Major Changes) (21 CFR 601.12(b)) 
 
Under 21 CFR 601.12(b), changes that have a substantial potential to have an adverse 
effect on the identity, strength, quality, purity, or potency of the product as they may 
relate to the safety or effectiveness of the product must be reported to FDA in a Prior 
Approval Supplement (PAS). 
                                                 
6http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/Guidances/Blood/ucm07
6729.htm. 
15    Contains Nonbinding Recommendations 
 
 
Under this regulation, the following kinds of manufacturing changes would fall within 
this category, warranting submission of your request to implement the following changes 
to your approved BLA as a PAS: 
 
  If you are a licensed blood establishment and you intend to change your Whole 
Blood manufacturing procedures to include leukocyte reduction.  
  If you are currently approved to manufacture leukocytes reduced blood 
components at a specific facility, and you intend to manufacture leukocytes 
reduced blood components at a different facility, not under an approved 
Comparability Protocol. 
  If you are approved to manufacture leukocytes reduced blood components, but 
intend to change your manufacturing process in a manner that presents a 
substantial potential to have an adverse effect on the identity, strength, quality, 
purity, or potency of the product as they may relate to the safety or effectiveness 
of the product and you are not making this change under an approved 
Comparability Protocol. 
  If you intend to manufacture leukocytes reduced blood components using an 
ABCS device new to your establishment and you are not making this change 
under an approved Comparability Protocol. 
  If you are requesting approval for a Comparability Protocol.  The Comparability 
Protocol described in 21 CFR 601.12(e) is a supplement that describes the 
specific tests and validation studies and acceptable limits to be achieved to 
demonstrate the lack of adverse effect for specified types of manufacturing 
changes on the identity, strength, quality, purity, or potency of the product as they 
may relate to the safety or effectiveness of the product.  A new Comparability 
Protocol, or a change to an existing one, requires approval from FDA prior to 
distribution of the product which, if approved, may justify a reduced reporting 
category for the particular change because the use of the protocol for that type of 
change reduces the potential risk of an adverse effect (21 CFR 601.12(e)). 
 
A Comparability Protocol is appropriate, but not required, if you wish to implement this 
change at multiple collection facilities under your direction and control, using the same 
process to manufacture automated leukocytes reduced components prepared by apheresis.   
 
We consider the recommendations in this guidance document to provide appropriate 
criteria for a biologics license supplement for leukocytes reduced blood or blood 
components.  You may use an alternate approach if such approach satisfies the 
requirements of the applicable statutes and regulations.  Your alternative procedure(s) 
may be acceptable if you demonstrate that the resulting leukocytes reduced blood or 
blood components are equivalent to components manufactured according to the 
procedures described in this guidance.   
 
You must not distribute in interstate commerce blood components made using a changed 
manufacturing process requiring a PAS until you have received our approval of your 
supplement (21 CFR 601.12(b)(3)). 
 
16    Contains Nonbinding Recommendations 
 
B.  Changes Being Effected in 30 Days (CBE-30) Supplement: Changes 
Requiring Supplement Submission at Least 30 Days Prior to Distribution of 
the Product Made Using the Change (21 CFR 601.12(c)) 
 
Under 21 CFR 601.12(c), changes that have a moderate potential to have an adverse 
effect on the identity, strength, quality, purity, or potency of the product as they may 
relate to the safety or effectiveness of the product must be reported to FDA in a Changes 
Being Effected in 30 days (CBE-30) supplement. 
 
You must submit your request to implement manufacturing changes with a moderate 
potential for an adverse effect to your approved BLA as a CBE-30 supplement under  
21 CFR 601.12(c).  The manufacturing changes described below are examples of 
changes that we believe fall within this category. 
 
  Implementation of a new collection facility for leukocytes reduced Platelets, 
Pheresis under an approved Comparability Protocol.   
  Certain software and hardware upgrades to the leukocyte reduction process for 
apheresis collection.  
 
You may distribute your blood components made using the change requested in your 
CBE-30 supplement in interstate commerce 30 days after we receive your supplement, 
unless we notify you otherwise (21 CFR 601.12(c)(4)). 
 
C.  Changes to be Described in an Annual Report (Minor Changes) (21 CFR 
601.12(d))  
 
Under 21 CFR 601.12(d), changes in the product, production process, quality controls, 
equipment, facilities, or responsible personnel that have a minimal potential to have an 
adverse effect on the identity, strength, quality, purity, or potency of the product as they 
may relate to the safety or effectiveness of the product must be documented in an annual 
report submitted each year within 60 days of the anniversary date of approval of the 
application.   
 
Changes from one type of FDA approved or cleared leukocyte reduction filter to another 
type of FDA approved or cleared leukocyte reduction filter is an example of a 
manufacturing change that we believe falls within this category, if implemented 
according to the instructions in the package insert without modification. 
 
D.  Submission of Documents 
 
1.  PAS: To comply with the requirements in 21 CFR 601.12(b)(3), the following 
must be contained in the supplement.  
 
  Identification of the components involved (i.e., those to be leukocytes 
reduced) and manufacturing facility(s) or area(s) affected, and a detailed 
description of the manufacturing change (including device collection 
technology for leukocyte reduction) (21 CFR 601.12(b)(3)(i) through 
17    Contains Nonbinding Recommendations 
 
(iii)).  We recommend that this information be documented in a cover 
letter and Form FDA 356h.  
  Product labeling for each component, if changed (21 CFR 601.12(f)).  We 
recommend submitting a Circular of Information (unless already on file at 
FDA).  To permit assessment of the manufacturing change we 
recommend including copies of the following SOPs: 
o  labeling including acceptable and unacceptable units; 
o  a description of training (or an example of training document) 
o  component manufacturing; 
o  failure investigation; 
o  quality control including sampling scheme, sample handlings, 
tracking and trending; and 
o  quarantine and disposition of unsuitable products. 
  A reference list of relevant SOPs (21 CFR 601.12(b)(3)(vii)).  We 
recommend submitting procedures unless they have been previously 
approved by the FDA.  
  Relevant validation protocols and data (21 CFR 601.12(b)(3)(vi)).  We 
recommend a summary of the validation protocol, including failure 
investigations.  
  A description of the methods used and studies performed to evaluate the 
effect of the change and the data derived from such studies  
(21 CFR 601.12(b)(3)(iv) through (v)).  We recommend submitting the 
following information and data: 
o  the device manufacturer; 
o  the device type; 
o  blood unit number; 
o  component description; 
o  date of collection; 
o  date of testing; 
o  result interpretation(s); 
o  the identity of the person performing the testing; 
o  the identity of the collection facility; 
o  the identity of the testing facility; 
o  evidence of QA oversight; and  
o  expected component specifications for the residual WBC count. 
 
Additionally, we recommend two months of QC data for component volume and 
residual WBC count per component.  
 
2.  Comparability Protocol (21 CFR 601.12(e)).  If you are an establishment with 
multiple manufacturing sites and wish to submit a Comparability Protocol to 
justify a reduced reporting category for a manufacturing change at multiple 
sites (see section VI.D.4 below), you must submit that protocol as a PAS  
(21 CFR 601.12(e)).  In addition to the information listed in section VI.D.1 
above, we recommend that you include the following: 
 
18    Contains Nonbinding Recommendations 
 
  Implementation plan; and 
  Proposed reporting category for changes made under the proposed 
Comparability Protocol. 
 
3.  CBE-30 submissions (excluding new facilities under an approved 
Comparability Protocol).  Under 21 CFR 601.12(c)(3) and  
21 CFR 601.12(b)(3)(i) through (vii), the following information must be 
contained in your CBE-30 submission: 
 
  Identification of the components involved (i.e., those to be leukocytes 
reduced) and manufacturing site(s) or area(s) affected, and a detailed 
description of the proposed manufacturing change (including device 
collection technology for leukocyte reduction).  We recommend that you 
document this information in a cover letter and Form FDA 356h.  To 
permit assessment of the documented manufacturing change, we 
recommend that you include copies of any new or revised SOPs. 
  Product labeling for each component (21 CFR 601.12(f)). 
  Relevant validation protocols and data.  We recommend that you submit a 
copy of the validation summary, including the investigation of any 
failures. 
  The data derived from studies.  We recommend two months of QC data 
for component volume, residual WBC count per component and percent 
recovery or minimum Red Blood Cell volume if applicable. 
  A description of the methods used and studies performed to evaluate the 
effect of the change and the data derived from such studies.  We 
recommend that you submit the following information: 
o  evidence of quality control oversight, including review and approval 
of manufacturing records by a quality assurance unit; and 
o  expected component specifications including residual WBC count and 
percent component recovery, if applicable. 
 
4.  CBE-30 submissions for new facilities under an approved Comparability 
Protocol.  To comply with 21 CFR 601.12(c)(3) and 21 CFR 601.12(b)(3)(i) 
through (vii), the following information must be included: 
 
  Identification of the components involved (i.e., those blood component(s) 
to be leukocytes reduced) and new manufacturing site(s) or area(s) 
affected, and a description of the implementation plan (manufacturing 
change including device collection technology for leukocyte reduction).  
Additionally, we recommend that this information be documented in a 
cover letter and FDA Form 356h.   
19    Contains Nonbinding Recommendations 
 
  Relevant validation protocols and data.  We recommend a summary of the 
validation protocol, including failure investigations to meet the 
requirement. 
  The data derived from studies.  We recommend two months of QC data.  
 
In addition, you should include the submission tracking number (STN) of the 
approved Comparability Protocol, and the STN(s) of changes to the SOPs 
associated with an approved Comparability Protocol. 
 
5.  Annual Report.  To comply with 21 CFR 601.12(d)(3), the following 
information must be included: 
 
  a list of all products involved; and 
  a full description of the manufacturing and controls changes including the 
manufacturing site(s) or area(a) involved.    
 
 
VII.  CONTACT INFORMATION 
 
Questions about licensing and specific review questions about leukocyte reduction should be 
directed to the Office of Blood Research and Review, Division of Blood Applications (DBA).  
Submit all registration forms (Form FDA 2830) and licensure applications/supplements to the 
Director, Center for Biologics Evaluation and Research (CBER).  Table 4 presents FDA contact 
information regarding leukocyte reduction. 
 
Table 4:  FDA Contact Information 
 
Director, Center for Biologics Evaluation and Research, HFM-370, 
Submissions:   Food and Drug Administration, 
Registrations   c/o Document Control Center, HFM-99, 
License Applications  1401 Rockville Pike, Suite 200N, 
Rockville, MD 20852-1448. 
Review Questions:  
Director, Division of Blood Applications, HFM-370,  
Licensing  
Food and Drug Administration, 
Red Blood Cells  
c/o Document Control Center, HFM-99, 
Whole Blood  
1401 Rockville Pike, Suite 200N, 
Platelets  
Rockville, MD 20852-1448, 
Platelets, Pheresis 
Voice 301-827-3543; Fax 301-827-3534. 
Plasma 
 
20    Contains Nonbinding Recommendations 
 
 
VIII.  REFERENCES 
 
1.  Alvarado-Ramy, F., Kuehnert, M., Alonso-Echanove, J., Sledge, L., Haley, R., Epstein, J., 
Vostal, J., and Pearson, M.  A multistate cluster of red blood cell transfusion reactions 
associated with use of a leukocyte reduction filter.  Transfusion Medicine 2006; 16:41-48. 
2.  Alonso-Echanove, J., Sippy, B.D., Chin, A.E., Cairns, L., Haley, R., Epstein, J.S., Richards, 
M.J., Edelhauser, H., Hedberg, K., Kuehnert, M.J., Jarvis, W.R., Pearson, M.L., and the 
Transfusion-Associated Red Eye Syndrome Study Group.  Nationwide Outbreak of Red Eye 
Syndrome Associated with Transfusion of Leukocyte-Reduced Red Blood Cell Units.  
Infection Control and Hospital Epidemiology 2006; 27(11):1146-1152. 
3.  Lankford, K.V., Fields, A.C., Langley, P.C. et al.  Ineffective prestorage leukoreduction 
(PSLR) of whole blood (WB) from African American donors with sickle cell trait (HB AS) 
versus controls.  Transfusion 1999; 39 (Suppl) 108S. 
4.  Williamson, L.M., Beard, M., Seghatchian, J., et al.  Leukocyte depletion of whole blood and 
red cells from donors with hemoglobin sickle trait.  Transfusion 1999; 39 (Suppl) 108S. 
5.  Gorlin, J,B,, Adams, C.L., Stefan, M.M., et al.  Variable leukoreduction on units from donors 
with sickle cell trait: A time-temperature donor reproducibility study.  Transfusion 2000; 40 
(Suppl) 55S.  
6.  Prihoda, L., Harbin, K., Thomas, A.  Leukocyte-Reduction filter failures:  Is hemoglobin S 
the answer?  Transfusion 2000; 40 (Suppl) 55S.  
7.  Harbin, K., Prihoda, L., Thomas, A.  Residual WBCs in leukocyte-reduction filtered 
hemoglobin S positive RBCs. Transfusion 2000; 40 (Suppl) 55S.  
8.  Dzik, W.H.  Leukoreduced blood components: Laboratory and clinical aspects.  In Rossis 
Principles of Transfusion Medicine.  Simon. T.L., Dzik, W.H., Snyder, E.L., Stowell, C.P., 
Strauss, R. (eds). 3rd ed. Philadelphia: Lippincott Williams & Wilkins 2002; 270-287.  
9.  Williamson, L.M., Wimperis, J.Z., Williamson, P., et al.  Bedside Filtration of Blood 
Products in the Prevention of HLA Alloimmunization:  A Prospective Randomized Study. 
Blood 1994; 83:3028-3035.  
10. The Trial to Reduce Alloimmunization to Platelets Study Group.  Leukocyte reduction and 
ultraviolet B irradiation of platelets to prevent alloimmunization and refractoriness to platelet 
transfusions.  New England Journal of Medicine 1997; 337:1861-1869.  
11. Bowden, R.A., Slichter, S.J., Sayers, M., et al.  A Comparison of Filtered Leukocyte-
Reduced and Cytomegalovirus (CMV) Seronegative Blood Products for the Prevention of 
Transfusion-Associated CMV Infection After Marrow Transplant.  Blood 1995; 86:3598-
3603.  
12. Strauss, R.G.  Leukocyte-reduction to prevent transfusion-transmitted cytomegalovirus 
infections.  Pediatric Transplantation 1999; 3 (Suppl 1); 19-22. 
13. Wu, Y. , Zou, S., Cable, R., Dorsey, K., Tang, Y., Hapip, C. A., Melmed, R., Trouern-Trend, 
J., Wang, J., Champion, M., Fang, C., and Dodd, R.  Direct assessment of cytomegalovirus 
transfusion-transmitted risks after universal leukoreduction. Transfusion 2009; 50: 776-786. 
14. Cyr, M., Eastlund, T., Blais, C., et al.  Bradykinin metabolism and hypotensive transfusion 
reactions.  Transfusion 2001; 41:136-150. 
15. Blajchman, M.A.  Transfusion-associated immunomodulation and universal white cell 
reduction: are we putting the cart before the horse?  Transfusion 1999; 39:665-670.  
16. Miller, J.P., Mintz, P.D.  The use of leukocyte-reduced blood components.  
Hematology/Oncology Clinics of North America 1995; 9:69-90.  
21    Contains Nonbinding Recommendations 
 
17. Reidner, C., Heim, M., Mempel, W., et al.  Possibility to Improve Preservation of Whole 
Blood by Leukocyte-Depletion before Storage.  Vox Sanguinis 1990; 59:78-82.  
18. Cardo, L.J., Salata, J., Harman, R., Mendez, J., Weina, P.J.  Leukodepletion filters reduce 
Leishmania in blood products when used at collection or at the bedside.  Transfusion 2006; 
46:896-902. 
19. Murphy, M.F.  New Variant Creutzfeldt-Jakob Disease (nvCJD):  The Risk of Transmission 
by Blood Transfusion and the Potential Benefit of Leukocyte-Reduction of Blood 
Components.  Transfusion Medicine Reviews 1999; 13:75-83. 
20. Llewelyn, C.A., Hewitt, PE, et al.  Possible transmission of variant Creutzfeldt-Jakob disease 
by blood transfusion.  Lancet 2004; 363: 417-21. 
21. Peden, A.H., Head, M.W., et al.  Preclinical vCJD after blood transfusion in a PRNP codon 
129 heterozygous patient.  Lancet 2004; 364(9433): 527-9. 
22. Health Protection Agency.  New case of transfusion-associated variant-CJD.  CDR Weekly 
2006; 16(6).  
23. Health Protection Agency.  4th case of variant CJD infection associated with blood 
transfusion.  Health Protection Report 2007; 1(3). 
24. FDA Memorandum:  Recommendations Regarding License Amendments and Procedures for 
Gamma Irradiation of Blood Components, July 22, 1993. 
25. Zoon, K.C., Jacobson, E.D., Woodcock, J.  Hypotension and Bedside Leukocyte Reduction 
Filters. International Journal of Trauma Nursing 1999; 5:121-122.  
26. Canadian Coordinating Office for Health Technology Assessment (CCOHTA).  
Leukoreduction:  The Techniques Used, Their Effectiveness, and Costs.  International 
Journal of Technology Assessment in Health Care 1998; 4:586-588.  
27. Dzik, S., AuBuchon, J., Jeffries, L., et al.  Leukocyte Reduction of Blood Components:   
Public Policy and New Technology.  Transfusion Medicine Reviews 2000; 14:34-52.  
28. FDA Guidance for Industry:  Process Validation:  General Principles and Practices, January 
2011.  
http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidance
s/UCM070336.pdf 
29. FDA Guidance for Industry: Use of Sterile Connecting Devices in Blood Bank Practices, 
November 2000.  
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/G
uidances/Blood/ucm076779.htm. 
30. FDA Guideline for Quality Assurance in Blood Establishments, July 11, 1995.   
http://www.fda.gov/downloads/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInf
ormation/Guidances/Blood/UCM164981.pdf. 
31. FDA Guidance for Industry and FDA Review Staff:  Collection of Platelets by Automated 
Methods, December, 2007.  
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/G
uidances/Blood/ucm073382.htm. 
32. Lachenbruch, P., Foulkes, M., Williams, A., Epstein, J.  Potential Use of the Scan Statistic 
For Quality Control in Blood Product Manufacturing.  Journal of Biopharmaceutical 
Statistics, 15: 353-366, 2005. 
33. Dzik, S., Moroff, G., Dumont, L.  A multicenter study evaluating three methods for counting 
residual WBCs in WBC-reduced blood components:  Nageotte hemocytometry, flow 
cytometry, and microfluorometry.  Transfusion 2000; 40:513-520.  
22    Contains Nonbinding Recommendations 
 
34. Circular of Information for the Use of Human Blood and Blood Components. AABB, 
Americas Blood Centers, American Red Cross, Armed Services Blood Program, December 
2009. 
35. Bodensteiner, D.  White cell reduction in blood from donors with sickle cell trait.  
Transfusion 1994; 34:84. 139S.  
36. Tinmouth, A.T., Naiman, R., Garel, B., et al.  Sickle cell trait associated with filter 
obstruction during pre-storage leukodepletion of red blood cell products.  Transfusion 2000; 
40 (Suppl) 59S.  
37. Salamon, N., Allen, S., Anderson, J.K.  Impact of sickle cell trait blood donations for a 
community blood center after universal leukoreduction.  Transfusion 2000; 40 (Suppl) 139S.  
38. Ledent, E., Berlin, G.  Factors influencing white cell removal from red cell concentrates by 
filtration.  Transfusion 1996; 36:714-718.  
39. FDA Guidance for Industry:  Recognition and Use of a Standard for Uniform Blood and 
Blood Component Container Labels, September 2006.   
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/G
uidances/Blood/ucm073362.htm.  
40. FDA Guidance for Industry:  Recommendations for Collecting Red Blood Cells by 
Automated Apheresis Methods - Technical Correction February 2001.  
http://www.fda.gov/BiologicsBloodVaccines/GuidanceComplianceRegulatoryInformation/G
uidances/Blood/ucm076756.htm. 
41. Romeu, J.L.  Understanding Binomial Sequential Testing.  RAC START, Volume 12, 
Number 2.  http://src.alionscience.com/pdf/BINSEQ.pdf. 
 
 
23    Contains Nonbinding Recommendations 
 
APPENDIX  
 
QC testing and sample size calculations based on the hypergeometric distribution  
 
Section III.F of this document describes a two-stage sampling approach to process validation 
based on the binomial distribution.  As discussed in Section IV.A, we consider this approach to 
be a scientifically sound statistical sampling and analytic plan for QC testing as well as for 
process validation.  One limitation of the binomial distribution-based approach, however, is that 
it assumes that the population of components being sampled from is infinite.  This assumption 
may not be ideal for sampling performed for monthly QC testing.  
 
A two-stage sampling approach based on the hypergeometric distribution may be used for 
monthly QC.  Unlike the binomial approach, the hypergeometric approach assumes that a finite 
number of components will be manufactured during a monthly QC period.  In general, the 
sample size for QC testing under the hypergeometric approach will be smaller than that for 
binomial distribution-based sampling.  However, you may prefer to use binomial distribution-
based sampling for other reasons, including familiarity and simplicity.  The decrease in sample 
size for the hypergeometric approach relative to the binomial approach is most noticeable when 
the total number of collections to be performed during a given QC period is small. 
 
The two-stage hypergeometric approach is similar in concept to the two-stage binomial 
approach described in Section III.F.  In the first stage, an initial representative sample of 
components with a predetermined sample size should be tested consecutively.  Identified non-
process failures may be excluded from the sample size and replaced.  Conformance can be 
demonstrated if an acceptable number of process failures are observed in this sample.  In the 
event that there is one more process failure than permitted in the initial sample, a second sample 
of components may be tested consecutively.  Conformance can be demonstrated if no further 
process failures are observed in the second sample.  The size of the second sample will depend 
on the size of the first sample, and may encompass the entire remaining population of 
components to be tested during a given QC period.   
 
Table A details possible sampling plans and sample sizes for two-stage QC testing based on the 
hypergeometric distribution for components other than platelets.  Table B provides sampling 
plans and sample sizes for platelet yield QC testing.  Each of the sampling plans contained in 
the tables satisfies the statistical criteria for successful QC testing provided in Section IV.A.  
The tables may be used as follows: 
 
1.  Determine the number of components that will be manufactured during a given QC 
period (i.e., one month of a given process at a given site).  This corresponds to the 
population size contained in the first column of the table.  Choose the appropriate row of 
the table corresponding to the population size for the given QC period.  In general, this 
will not be known precisely in advance and will need to be estimated.  It is important 
that the estimated population size be at least as large as the true population size.  That is, 
you should choose the maximum possible number of components for a given QC period 
rather than, e.g., an average number of components. 
24    Contains Nonbinding Recommendations 
 
2.  Once you have identified the appropriate row corresponding to the population size for a 
given QC period, you can choose from up to three possible two-stage sampling plans, 
distinguished by the number of failures allowed in the first stage:  zero failures, one 
failure or two failures. 
3.  The two columns headed by the sampling plan chosen in Step 2 above contain the 
required sample sizes for the first and second stages of the sampling, respectively.  In 
some cases the sample size for the second stage is denoted All.  This indicates that 
every component in the given QC period must be tested in the event of one excess 
process failure in the first sampling stage.  In other cases, the sample size for the second 
stage is denoted with a dash.  This indicates that a two-stage approach is not possible for 
the given population size and first stage sample, and that one excess process failure in 
the first stage means overall failure of the QC testing for that QC period.  
 
As an example of this approach, suppose that you intend to collect 100 leukocyte-reduced 
plasma components on a given instrument at a given site during the next month.  Note first that 
you may test every one of these 100 units and, if 4 or fewer process failures are observed, the 
process failure rate is less than 5% for that QC period.  Adopting instead a statistical sampling 
strategy, you may consult Table A and choose one of the three sampling plans provided in the 
row corresponding to population size of 100.  Suppose you choose the zero failures allowed 
sampling plan in this row, which specifies a first stage sample size of 45 components and a 
second stage sample size of 34 components.  You would therefore test the first 45 consecutive 
components for that month.  If no process failures were observed among these 45 components, 
the process would be considered to be in control and no further QC testing would be required 
during that month.  If one process failure is observed among the first 45 components, you would 
test an additional 34 consecutive components.  If no further process failures were observed 
among the second stage sample of 34 components, the process would be considered to be in 
control and no further testing would be required.  If two or more process failures were observed 
during the first stage sample of 45 components or if one or more process failures were observed 
during the second stage sample of 34, the process would not be in control and QC testing would 
have failed. 
 
Statistical derivation of the sample sizes in Tables A and B 
 
In Table A, for each fixed population size, N, and number of allowed failures, m, the first stage 
sample size was calculated as the minimum number n  such the probability of observing m or 
1
fewer process failures in a sample of size n  from a population of size N is at most 5% when the 
1
true process failure rate is 5% or more.  For example, assume that 100 components will be 
collected during a QC period.  Using the zero failures allowed first stage sampling plan, it can 
be calculated based on the hypergeometric probability distribution that the probability of 
observing zero failures in a sample of 45 components is 0.0462 if the true failure rate is at least 
5% (that is, if there are at least 5 process failures among the 100 components to be collected).  
On the other hand, the probability of observing zero failures in a sample of 44 components is 
0.0507.  Therefore, 45 is the minimum sample size such that the probability of observing zero 
failures is less than 5% when the true failure rate of at least 5%. 
 
25    Contains Nonbinding Recommendations 
 
Once the first stage sample size has been determined, to obtain the second stage sample size, we 
first calculated 0.05 minus the probability of observing m or fewer process failures in the first 
stage when the true failure rate is at least 5%.  Continuing our example above, this quantity 
would be 0.05  0.0462 = 0.0038.  The second stage sample size was then calculated as the 
minimum number n  such that the probability of observing (i) one failure among the first n  
2 1
samples at stage one and (ii) no failures among the n  samples at stage two is less than 0.05 
2
minus the probability of observing m or fewer process failures in the first stage when the true 
failure rate is at least 5%.   In the example here, with n  = 33, this probability is 0.0044, which is 
2
not less than 0.0038, whereas with n = 34, this probability is 0.0036 which is less than 0.0038. 
2 
Therefore, the required sample size at stage two for this example is 34.  Romeu (Ref. 41) adopts 
the same algorithm for an infinite population size based on the binomial distribution. 
 
The derivation of the sample sizes in Table B followed the same process, but was based on 
ruling out a true failure rate of at least 25% rather than 5% as in Table A.  Note that 
hypergeometric sampling schemes other than those presented in Tables A and B are possible.  
For instance, in some cases it is possible to use a larger first stage sample size and smaller 
second stage than that provided in the tables.  We will consider any sampling plan that meets the 
criteria described in Section IV.A. 
   
26    Contains Nonbinding Recommendations 
 
Table A. Sampling scheme for quality control testing based on hypergeometric distribution 
(95%/95%).   
Use for all QA and monitoring assessments under Section IV, except in accessing platelet yield.  
See Table B for assessment of platelet yield. 
95%/95%1 
95% confidence that more than 95% of the components meet the standard 
Sample size 
# of failures  0  1  2 
Population  allowed in  failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
30  1  23  All4  30  -  -  - 
31  1  24  All  31  -  -  - 
32  1  25  All  32  -  -  - 
33  1  26  All  33  -  -  - 
34  1  26  All  34  -  -  - 
35  1  27  All  35  -  -  - 
36  1  28  All  36  -  -  - 
37  1  29  All  37  -  -  - 
38  1  30  All  38  -  -  - 
39  1  30  All  39  -  -  - 
40  1  31  All  39  -  -  - 
45  2  28  155  39  All6  45  - 
50  2  31  18  43  All  50  - 
55  2  35  17  48  All  55  - 
60  2  38  19  52  All  60  - 
65  3  34  23  49  13  59  All7 
70  3  37  23  52  17  63  All 
75  3  39  29  56  17  68  All 
80  3  42  28  60  17  72  All 
85  4  38  30  56  19  69  13 
90  4  40  34  59  22  73  14 
95  4  42  41  62  25  77  15 
100  4  45  34  65  30  81  16 
120  5  47  40  69  37  87  25 
140  6  48  51  72  44  92  28 
160  7  49  62  75  39  95  42 
180  8  50  64  77  41  98  44 
200  9  51  61  78  51  101  39 
220  10  52  57  79  62  103  42 
240  11  52  73  80  71  104  55 
260  12  53  61  81  69  106  47 
280  13  53  72  82  63  107  52 
300  14  54  60  83  58  108  56 
320  15  54  67  83  94  109  57 
340  16  54  75  84  65  110  55 
360  17  54  91  85  57  111  53 
 
27    Contains Nonbinding Recommendations 
 
95%/95%1 
95% confidence that more than 95% of the components meet the standard 
Sample size 
# of failures  0  1  2 
Population  allowed in  failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
380  18  55  65  85  66  111  70 
400  19  55  70  85  85  112  60 
450  22  54  78  84  111  111  62 
500  24  56  69  87  70  114  76 
550  27  55  76  86  72  113  75 
600  29  56  85  88  74  116  67 
650  32  56  69  87  78  115  66 
700  34  57  71  89  70  117  73 
750  37  56  80  88  74  116  73 
800  39  57  78  89  95  118  71 
850  42  56  96  89  67  117  72 
900  44  57  86  90  73  119  66 
950  47  57  73  89  81  118  67 
1000  49  57  95  90  86  119  82 
1500  74  58  81  91  95  121  75 
2000  99  58  92  92  78  122  72 
2500  124  58  101  92  91  122  91 
3000  149  58  111  92  109  123  71 
3500  174  58  124  93  74  123  77 
4000  199  58  149  93  77  123  83 
4500  224  59  79  93  79  123  89 
5000  249  59  80  93  81  123  95 
6000  299  59  81  93  85  123  113 
7000  349  59  82  93  88  124  72 
8000  399  59  83  93  91  124  74 
9000  449  59  84  93  93  124  76 
10000  499  59  85  93  95  124  77 
11000  549  59  85  93  97  124  79 
12000  599  59  85  93  99  124  80 
13000  649  59  86  93  100  124  81 
14000  699  59  86  93  102  124  82 
15000  749  59  86  93  103  124  83 
20000  999  59  87  93  108  124  86 
25000  1249  59  88  93  112  124  88 
30000  1499  59  88  93  116  124  90 
35000  1749  59  89  93  119  124  91 
40000  1999  59  89  93  121  124  92 
45000  2249  59  89  93  123  124  93 
50000  2499  59  89  93  125  124  93 
55000  2749  59  89  93  126  124  94 
28    Contains Nonbinding Recommendations 
 
 
95%/95%1 
95% confidence that more than 95% of the components meet the standard 
  Sample size   
# of failures  0   1  2 
Population  allowed in  failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
60000  2999  59  89  93  128  124  94 
2.00E+078  999999  59  90  93  163  124  100 
1The inference that with 95% confidence more than 95%  of the components meet the standard is only 
applicable to the finite population from which the samples are drawn.  
2The population size is the total number of products manufactured in a given quality control (QC) period (e.g., 
one month for a monthly QC) at a given site using a given instrument, etc.  
3Additional testing if allowable process failures are exceeded (see footnotes 4 through 7) 
4For a population size of 30, if you select a sample size of 23 and find one failure, test all the remaining 
components and no additional failures are allowed. 
5For a population size of 45, if you select a sample size of 28 and find one failure, test 15 additional samples 
and no additional failures are allowed. 
6For a population size of 45, if you select a sample size of 39 and find two failures, test the remaining 
components and no additional failures are allowed. 
7For a population size of 65, if you select a sample size of 59 and find three failures, test the remaining 
components and no additional failures are allowed. 
8With a very large population size, the sample size based on hypergeometric distribution converges to the 
sample size based on the binomial distribution although the convergence is very slow in some cases. 
29    Contains Nonbinding Recommendations 
 
Table B.  Sampling scheme for quality control testing based on hypergeometric distribution 
(95%/75%). 
Under 21 CFR 640.24(c), the platelet product must yield an acceptable count in at least 75 
percent of the units tested.  Table B applies only to platelet yield and does not pertain to the other 
aspects of QC testing of platelet products (e.g., assessing white count, pH) where the appropriate 
measure is 95%/95%. 
95%/75%1 
95% confidence that more than 75% of the components meet the standard 
# of  Sample size 
failures  0  1  2 
Population  allowed in   failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
30  7  9  6  13  8  17  6 
31  7  9  7  14  5  18  5 
32  7  9  9  14  8  18  9 
33  8  9  6  13  8  17  7 
34  8  9  7  14  5  18  5 
35  8  9  8  14  7  18  8 
36  8  9  14  15  5  19  6 
37  9  9  7  14  5  18  5 
38  9  9  8  14  7  18  8 
39  9  9  10  15  5  19  5 
40  9  10  7  15  6  19  9 
45  11  9  9  14  8  19  5 
50  12  9  15  15  6  19  10 
55  13  10  8  15  10  20  7 
60  14  10  9  16  7  21  6 
65  16  10  7  15  9  20  7 
70  17  10  8  16  6  20  14 
75  18  10  10  16  8  21  7 
80  19  10  11  16  9  21  10 
85  21  10  9  16  7  21  7 
90  22  10  10  16  8  21  8 
95  23  10  11  16  10  21  13 
100  24  10  14  16  14  22  7 
120  29  10  17  17  7  22  9 
140  34  11  8  17  8  22  10 
160  39  11  8  17  9  22  13 
180  44  11  9  17  9  22  17 
200  49  11  9  17  9  23  7 
220  54  11  9  17  10  23  8 
240  59  11  9  17  10  23  8 
260  64  11  9  17  10  23  8 
280  69  11  9  17  11  23  8 
300  74  11  9  17  11  23  9 
320  79  11  10  17  11  23  9 
30    Contains Nonbinding Recommendations 
 
 
95%/75%1 
95% confidence that more than 75% of the components meet the standard 
# of  Sample size 
failures  0  1  2 
Population  allowed in  failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
340  84  11  10  17  12  23  9 
360  89  11  10  17  12  23  9 
380  94  11  10  17  12  23  9 
400  99  11  10  17  12  23  10 
450  112  11  10  17  12  23  9 
500  124  11  10  17  13  23  10 
550  137  11  10  17  12  23  10 
600  149  11  10  17  14  23  11 
650  162  11  10  17  13  23  10 
700  174  11  10  17  14  23  11 
750  187  11  10  17  14  23  11 
800  199  11  10  17  15  23  12 
850  212  11  10  17  14  23  11 
900  224  11  10  17  15  23  12 
950  237  11  10  17  15  23  12 
1000  249  11  10  17  16  23  12 
1500  374  11  11  17  17  23  13 
2000  499  11  11  17  19  23  14 
2500  624  11  11  17  20  23  14 
3000  749  11  11  17  21  23  15 
3500  874  11  11  17  21  23  15 
4000  999  11  11  17  22  23  15 
4500  1124  11  11  17  23  23  15 
5000  1249  11  11  17  23  23  15 
6000  1499  11  11  17  24  23  16 
7000  1749  11  11  17  26  23  16 
8000  1999  11  11  17  27  23  16 
9000  2249  11  11  17  28  23  16 
10000  2499  11  11  17  30  23  16 
11000  2749  11  11  17  33  23  16 
12000  2999  11  11  17  43  23  16 
13000  3249  11  11  18  8  23  16 
14000  3499  11  11  18  8  23  16 
15000  3749  11  11  18  8  23  16 
20000  4999  11  11  18  8  23  16 
25000  6249  11  11  18  8  23  17 
30000  7499  11  11  18  8  23  17 
35000  8749  11  11  18  8  23  17 
40000  9999  11  11  18  8  23  17 
45000  11249  11  11  18  8  23  17 
31    Contains Nonbinding Recommendations 
 
 
95%/75%1 
95% confidence that more than 75% of the components meet the standard 
# of  Sample size 
failures  0  1  2 
Population  allowed in  failures  failure  failures 
size2  population  allowed  Add3  allowed  Add3  allowed  Add3 
50000  12499  11  11  18  8  23  17 
55000  13749  11  11  18  8  23  17 
60000  14999  11  11  18  8  23  17 
2.00E+078  4999999  11  11  18  8  23  17 
1The inference that with 95% confidence more than 75% of the components meet the standard is only applicable 
to the finite population from which the samples are drawn.  
2The population size is the total number of products manufactured in a given quality control (QC) period (e.g., 
one month for a monthly QC) at a given site using a given instrument, etc.  
3Additional testing if allowable process failures are exceeded (see footnotes 4 through 7) 
4For a population size of 30, if you select a sample size of 23 and find one failure, test all the remaining 
components and no additional failures are allowed. 
5For a population size of 45, if you select a sample size of 28 and find one failure, test 15 additional samples 
and no additional failures are allowed. 
6For a population size of 45, if you select a sample size of 39 and find two failures, test the remaining 
components and no additional failures are allowed. 
7For a population size of 65, if you select a sample size of 59 and find three failures, test the remaining 
components and no additional failures are allowed. 
8With a very large population size, the sample size based on hypergeometric distribution converges to the 
sample size based on the binomial distribution although the convergence is very slow in some cases. 
32