Guidance for Industry and FDA 
Staff 
 
 
Impact-Resistant Lenses: 
Questions and Answers 
 
 
Document issued on: September 2, 2010 
 
 
 This document supersedes Impact-Resistant Lenses: Questions and 
Answers, September 1987.  
 
The draft of this document was issued on October 26, 2007. 
 
\ 
For questions regarding this document contact Walter Snesko at 301-796-6882 or 
walter.snesko@fda.hhs.gov.   
 
 
 
 
 
 
 
 
 
 
 
 
 
U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Devices and Radiological Health 
 
 
Division of Small Manufacturers, International and Consumer Assistance 
Office of Communication, Education, and Radiation Programs 
 
  Contains Nonbinding Recommendations 
 
Preface 
 
 
 
Public Comment 
 
Written comments and suggestions may be submitted at any time for Agency consideration to 
the Division of Dockets Management, Food and Drug Administration, 5630 Fishers Lane, rm. 
1061, (HFA-305), Rockville, MD, 20852.  Alternatively, electronic comments may be 
submitted to http://www.regulations.gov. When submitting comments, please refer to Docket 
No. FDA-2007-D-0367.  Comments may not be acted upon by the Agency until the document is 
next revised or updated. 
 
 
Additional Copies 
Additional copies are available from the Internet.  You may also send an e-mail request to 
dsmica@fda.hhs.gov to receive an electronic copy of the guidance or send a fax request to 301-
827-8149 to receive a hard copy.  Please use the document number (23) to identify the guidance 
you are requesting. 
 
 
  Contains Nonbinding Recommendations 
 
 
 
Table of Contents 
 
 
Introduction ..................................................................................................................................... 1 
Overview ......................................................................................................................................... 2 
Prescription and Non-Prescription Glass Lenses ............................................................................ 4 
Prescription and Non-Prescription Plastic Lenses ........................................................................... 4 
Finished Lenses................................................................................................................................ 5 
Lens Blanks (Semi-Finished Lens) ................................................................................................. 5 
Plano (Non-Corrective) Lens .......................................................................................................... 5 
Sunglasses ........................................................................................................................................ 6 
Novelty and Children's "Toy" Sunglasses ....................................................................................... 6 
Other Lens Types ............................................................................................................................ 7 
Who Should Test and When ........................................................................................................... 9 
Testing Apparatus and Procedure ................................................................................................. 10 
Sampling Plans .............................................................................................................................. 12 
Records .......................................................................................................................................... 14 
Exemptions .................................................................................................................................... 14 
Importing Lenses, Eyeglasses, and Sunglasses ............................................................................. 14 
Retail Stores and Optical Laboratories ......................................................................................... 17 
Dispensing Untested Lenses .......................................................................................................... 17 
Frames and Designs ....................................................................................................................... 18 
Labeling ......................................................................................................................................... 19 
Additional Regulatory Requirements............................................................................................ 19 
Consumer Information .................................................................................................................. 20 
APPENDIX A.   21 CFR  801.410  Use of impact-resistant lenses in eyeglasses and sunglasses.
 ....................................................................................................................................................... 20 
APPENDIX B.  Photograph of Drop Ball Test Unit (Impact Tester) ......................................... 20 
APPENDIX C.   Certification Statement of Impact Resistance .................................................. 20  Contains Nonbinding Recommendations 
 
 Guidance for Industry and FDA Staff 
 
  
 
Impact-Resistant Lenses: 
Questions and Answers 
 
 
This guidance represents the Food and Drug Administration's (FDA's) 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 FDA staff responsible for implementing this guidance.  If 
you cannot identify the appropriate FDA staff, call the appropriate number listed on the 
title page of this guidance.  
 
Introduction  
 
Eyeglasses and sunglasses (eyewear) that are intended to affect the structure or function of the 
body or intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, 
treatment, or prevention of disease, are devices within the meaning of section 201(h) of the 
Federal Food, Drug, and Cosmetic Act (the act) (21 U.S.C. 321(h)).  These devices are subject 
to applicable device regulations under Title 21, Code of Federal Regulations.  Impact-resistant 
lenses reduce the number of eye injuries from eyeglasses and sunglasses.  Glass lenses, plastic 
lenses, or laminated glass lenses can be made impact resistant by any method.  However, lenses 
generally must be capable of withstanding the impact test described in 21 CFR 801.410.  This 
guidance answers questions for manufacturers, importers, and testing laboratories on such topics 
as test procedures, lens testing apparatus, record maintenance, and exemptions to testing. 
 
This guidance is a revision of Impact-Resistant Lenses: Questions and Answers (FDA 87-
4002), issued September 1987. This guidance updates answers to questions that industry and 
consumers frequently ask FDA about impact-resistant lenses and FDA regulation of eyewear. 
The revision reflects the exemption of sunglasses from the Premarket Notification (510(k)) 
requirement effective February 19, 1998 (21 CFR 886.5850(b)).  The revised document also 
includes a more detailed discussion about lens blanks, semi-finished, finished, and plano lenses, 
as well as import procedures. We use the terms "eyeglasses" and "spectacles" interchangeably in 
this document. 
 
FDA's guidance documents, including this guidance, do not establish legally enforceable 
responsibilities.  Instead, guidances describe the Agency's current thinking on a topic and should 
be viewed only as recommendations, unless specific regulatory or statutory requirements are 
  1  Contains Nonbinding Recommendations 
 
cited.  The use of the word should in Agency guidances means that something is suggested or 
recommended, but not required.  
 
 
Overview 
 
Eyewear products regulated by FDA are commonplace in the daily lives of the vast majority of 
the general public.  FDA believes that impact-resistant lenses are an essential component of the 
safe design of these devices. 
 
The use of impact-resistant lenses in eyeglasses and sunglasses is addressed in 21 CFR 801.410.  
Except in those cases where the physician or optometrist finds that such lenses will not fulfill the 
visual requirements of the particular patient, directs the use of other lenses in writing, and gives 
written notification to the patient, eyeglasses and sunglasses must be fitted with impact-resistant 
lenses (21 CFR 801.410(c)(1)). Glass lenses, plastic lenses, or laminated glass lenses can be 
made impact resistant by any method.  However, in accordance with 21 CFR 801.410(c)(2), all 
such lenses must be capable of withstanding the impact test described in 21 CFR 801.410(d)(2).  
Although lenses must be impact resistant, it does not make the lenses shatterproof.   
 
The number of lenses actually tested for impact resistance within each batch or lot varies 
depending on material and type of lens (21 CFR 801.410(c)(3)). You must perform impact 
testing on each glass lens for prescription use (21 CFR 801.410(c)(3)). However, you may test a 
statistically significant sample of lenses from each production batch for testing of over-the-
counter (OTC) glass lenses, glass laminate (prescription or OTC), and plastic lenses 
(prescription or OTC) for impact resistance. Certain lenses, which are prescribed infrequently for 
specific, uncommon visual needs, have physical designs that make them unsuitable for impact 
testing.  These lenses (see 21 CFR 801.410(c)(3) for specific types) should be rendered impact 
resistant but need not be tested.   
Consumers, manufacturers, and sellers should remember that the strength of any lens is related 
to the condition of its surface and edge.  All lenses lose their impact strength in direct proportion 
to the breakdown of the polished and edged surfaces.  The greater the number and depth of 
scratches or the poorer the edge finish, the weaker the lens becomes.  For consumers, there is an 
inherent hazard in continuing to wear scratched lenses because their impact strength is reduced.  
Spectacle wearers also should be aware that plastic lenses are not necessarily impact resistant 
simply because they are manufactured of a plastic material.    
 
FDA does not regulate other forms of eyewear, such as safety glasses and sports glasses 
(including swimmers' racing goggles, ski goggles, and racquetball eye guards), as devices unless 
they have ultraviolet (UV) prescription lenses. 
 
We recommend you also refer to Guidance Document for Nonprescription Sunglasses at 
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm0
73951.htm.  
  2  Contains Nonbinding Recommendations 
 
 
For more information on this topic, you may contact the Division of Small Manufacturers, 
International, and Consumer Assistance (DSMICA) by phone at 1-800-638-2041, by fax at 
301-847-8149, by e-mail at dsmica@fda.hhs.gov, or write to the following address:  
 
U.S. Food and Drug Administration 
Center for Devices and Radiological Health 
Office of Communication, Education and Radiation Programs 
Division of Small Manufacturers, International, and Consumer Assistance 
10903 New Hampshire Ave.   
WO66-4613 
Silver Spring, Maryland 20993 
  3  Contains Nonbinding Recommendations 
 
Prescription and Non-Prescription Glass Lenses 
 
1.  Q.  What are the impact testing requirements for prescription (Rx) glass lenses? 
 
  A.  The manufacturer must test each finished Rx glass lens individually for impact resistance 
(21 CFR 801.410(c)(3)).  The lens must be capable of withstanding the impact test 
provided in 21 CFR 801.410(d)(2) as described later in this document under Testing 
Apparatus and Procedure.  You should perform testing after the lens has been edged 
(cut to the shape of the frame) but before the lens is put into the frame. 
 
2.  Q.  What are the impact testing requirements for non-prescription (over-the-counter) glass 
lenses, e.g., magnifying spectacles and nonprescription sunglasses?  Magnifying 
spectacles are intended to be worn by a patient who has impaired vision to enlarge 
images.  See 21 CFR 886.5840.  Nonprescription sunglasses are intended to be worn to 
protect the eyes from bright sunlight but not to provide refractive corrections.  See 21 
CFR 886.5850. 
 
  A.  Under 21 CFR 801.410(c)(3), you must test a statistically significant sample of over-the-
counter glass lenses from each production batch. The sample must be representative of 
the finished forms as worn by the wearer, including forms that are of minimal lens 
thickness and have been subjected to any treatment used to impart impact resistance. 
You must test all nonprescription lenses in either uncut-finished or finished form.  21 
CFR 801.410(c)(3).  If you choose to test the finished form, you should perform testing, 
on a sample, after the lens has been edged (cut to the shape of the frame) but before 
being put into the frame.   
 
3.  Q.  Can a glass lens that is chemically or thermally treated for impact resistance be further 
processed? 
 
  A.  You may re-edge or modify the power (resurface) of lenses that have been chemically or 
thermally treated for impact resistance.  However, this may significantly reduce the 
resistance to impact. You should re-treat and retest the lenses before delivering them to 
the end customer.  
 
Prescription and Non-Prescription Plastic Lenses 
 
4.  Q.  What are the impact testing requirements for prescription (Rx) and non-prescription 
plastic lenses? 
 
  A.  Under 21 CFR 801.410(c)(3), you must test a statistically significant sample of 
prescription or non-prescription plastic lenses from each production batch. The sample 
must be representative of the finished forms as worn by the wearer, including forms that 
are of minimal lens thickness and have been subjected to any treatment used to impart 
impact resistance. You must test plastic lenses in either uncut-finished or finished form. 
  4  Contains Nonbinding Recommendations 
 
21 CFR 801.410(c)(3).  If you choose to test the finished form, you should perform 
testing on a sample after the lens has been edged (cut to the shape of the frame) but 
before being put into the frame.   
 
 
Finished Lenses  
 
5.  Q.  What is meant by a uncut finished or finished form in 21 CFR 801.410(c)(3)?  
 
  A. Uncut-finished means a lens with both surfaces optically shaped but not yet edged. 
FDA considers a lens to be a "finished device" or  in "finished form" when both surface 
and edging operations have been completed, and coating and treatment for impact 
resistance has been applied, if appropriate.  
 
Lens Blanks (Semi-Finished Lens) 
 
6.  Q.  What is a "semi-finished lens?  
 
  A.  FDA considers a "semi-finished lens to be a lens with only one surface (usually front 
surface) shaped or molded to a specific curve. 
   
7.  Q.  Is the manufacturer of semi-finished lens required to perform the impact testing? 
 
  A.  No. A semi-finished lens needs further processing that may weaken the lens. You must 
test the uncut-finished or, the finished lens if it is a glass lens for prescription use. 21 
CFR801.410(c)(3) 
 
Plano (Non-Corrective) Lens 
 
8   Q.  What is a "plano" lens? 
 
  A.  A plano lens is a lens with no corrective power and essentially no refracting ability. For 
example, when one eye needs refractive correction and the other eye does not, you may 
use the plano lens for the eye that requires no correction. 
 
9.  Q.  Does impact testing apply to retailers that put plano lenses in sunglass frames or that put 
lenses into an eyeglass frame in which one lens is plano and the other lens is corrective?  
 
  A.  Yes. Testing depends on lens material.  Retailers that process lenses (grind and shape) 
must render the plano lenses impact resistant. Finished glass lenses should be tested 
regardless of optical power while plastic lenses can be statistically sampled or certified to 
the design testing specifications.  
  5  Contains Nonbinding Recommendations 
 
Sunglasses 
 
10. Q.  Does impact testing apply to finished non-prescription sunglass lenses, i.e., sunglass 
lenses that need only to be inserted into a frame?  
 
  A.  Yes.  Under 21 CFR 801.410(c)(3), you must test a statistically significant sample of 
sunglass lenses from each production batch. The sample must be representative of the 
finished forms, including forms that are of minimal lens thickness and have been 
subjected to any treatment used to impart impact resistance. You must test all lenses in 
uncut-finished or finished form. 21 CFR 801.410(c)(3).  If you choose to test the 
finished form, you should perform testing on a sample after the lens has been edged (cut 
to the shape of the frame) but before being put into the frame.   
 
11. Q.  Are clip-on sunglass lenses subject to impact testing? 
 
  A.  Yes (21 CFR 801.410 (c)(3)).  However, FDA intends to exercise its enforcement 
discretion regarding impact testing based on the following factors:  
  
1.  Whether the clip-ons cannot be worn alone, but can only be worn with lenses that are 
impact resistant. 
2.  Whether the clip-ons are designed so that they may be worn only on the outside (side 
distal from the eye) of the prescription lenses. 
3.  Whether the clip-ons are the same size or smaller than the prescription lenses upon 
which they are intended to be worn.  
 
Novelty and Children's "Toy" Sunglasses 
 
12. Q.  Is novelty eyewear subject to the impact testing regulations? 
 
A.  FDA strongly recommends that you conduct impact testing of any glass or plastic lenses 
used in novelty eyewear to help ensure the safe design of these products.  
 
        In general, FDA does not require impact testing of novelty eyewear if:   
 
(1) the item is a novelty item, which is not intended to provide children (or other users) 
with corrective power or protection from bright sunlight; and  
(2) a warning label stating that the item is not to be worn outside as sunglasses to protect 
the eyes against strong sunlight is placed on eyewear that has dark-colored lenses. 
 
However, all novelty eyewear may be subject to regulation by the Consumer Product 
Safety Commission (CPSC) under the provisions of the Federal Hazardous Substances 
  6  Contains Nonbinding Recommendations 
 
Act (FHSA)1. The regulations are found in 16 CFR 1500, Hazardous Substances and 
Articles; Administration and Enforcement Regulations, and 16 CFR 1501, Method for 
Identifying Toys and Other Articles Intended for Use by Children Under 3 Years of Age 
Which Present Choking, Aspiration, or Ingestion Hazards Because of Small Parts.  
   
13. Q.  Are children's sunglasses subject to the impact testing regulations?  
 
  A.  Children's sunglasses, intended for use by a child in the protection of his or her eyes from 
bright sunlight, are subject to all of the applicable requirements, including impact 
testing.  Childrens sunglasses that are devices within the meaning of section 201(h) of 
the act are also subject to the CPSC regulations under 16 CFR parts 1500 and 1501 
discussed previously in response to Question #12.  
 
If they meet the criteria outlined in response to Question #12, childrens sunglasses may 
be novelty glasses that are not regulated as medical devices by FDA.  However, they, 
too, may still be subject to the hazardous substance regulations of the CPSC (see 16 
CFR Parts 1500 and 1501). 
 
14. Q.  What are the testing requirements for children's "toy" sunglasses?  
  
  A.  If childrens toy sunglasses are intended to provide protection from bright sunlight, such 
as sunglasses sold or given away in fast food restaurants as promotional items, they must 
meet the impact test (21 CFR 801.410).   
 
Other Lens Types 
 
15.  Q. What is the difference between safety lenses and impact-resistant lenses? 
 
  A.  Safety lenses have more stringent impact-resistant requirements and are used in an 
industrial setting.  Impact-resistant lenses are used in (1) eyeglasses, (2) sunglasses, and 
(3) noncorrective fashion eyewear. 
 
16.  Q. What regulations apply to industrial safety lenses? 
 
                                                           
1 The Federal Hazardous Substances Act regulations in 16 CFR 1500.3(a)(1), defines "Act" as 
the Federal Hazardous Substances Act (Pub. L. 86-613, 74 Stat. 372-81 (15 U.S.C. 1261-74)), 
and amendments to such Act.   
  7  Contains Nonbinding Recommendations 
 
  A.  Both FDA and the Occupational Safety and Health Administration (OSHA) regulate 
industrial prescription safety lenses.  Under 21 CFR 801.410, these lenses must be 
impact resistant.  If the industrial prescription safety lenses meet OSHA requirements 
under 29 CFR 1910.133(b), then FDA believes it is appropriate to exercise its 
enforcement discretion with respect to the need for further impact testing under 21 CFR 
801.410(d) for such lenses. Under 29 CFR 1910.133(b), protective eye devices must 
comply with ANSI Z87.11989, American National Standard Practice for 
Occupational and Educational Eye and Face Protection, (if purchased after July 5, 
1994) and ANSI USA Standard for Occupational and Educational Eye and Face 
Protection, Z87.11968 (if purchased before July 5, 1994).  FDA considers ANSI 
Z87.1 to meet or exceed impact testing under 21 CFR 801.410. 
 
 OSHA, not FDA, regulates non-prescription safety lenses.  FDA impact test 
requirements do not apply to non-prescription safety lenses.  
 
17. Q.  What regulations apply to sports goggles, such as skiing, swimming, and snorkeling? 
 
  A.  Sports goggles with prescription lenses are regulated as devices.  Manufacturers must 
meet all applicable device regulations, including impact resistance (21 CFR 801.410), 
establishment registration (21 CFR Part 807), device listing (21 CFR Part 807), quality 
system regulation (21 CFR Part 820), and medical device reporting (21 CFR Part 803).  
Prescription sports goggles should also meet the appropriate safety standards for the 
sport. 
 
Non-corrective sports goggles that do not make any sun protection claims are not 
regulated as devices.  Therefore, no device regulations, such as registration or listing, 
apply.  
   
18. Q.  What regulations apply if sports goggles use the following claims: "Blocks UV,  
Blocks Sunrays," or makes other sunglass claims? 
 
  A.  FDA regulates goggles, including sports goggles and tanning bed goggles, that make 
such claims as sunglasses. Therefore, goggles making such claims must meet the same 
regulations as sunglasses, including impact resistance. 21 CFR 801.410.  
19. Q.  What regulations apply to demonstration lenses used in eyeglasses and sunglasses for 
retail display?  
 
A.  Demonstration lenses are typically not rendered impact resistant as they are not intended 
to be sold to consumers. You should take precautions to assure that display units 
containing demonstration lenses that are not impact-resistant are not sold to the 
consumer.  Manufacturers of eyeglass or sunglass frames with demonstration lenses can 
use various options to ensure these units are not used by consumers.  The options include 
the following: 
 
1. You may have the word demonstration etched in the lower quadrant of at least one 
lens in each pair of eyeglasses. The letters should be large enough to be seen easily 
with normal vision. 
  8  Contains Nonbinding Recommendations 
 
2. You may draw a visible line through the center of the lens. 
3. You may remove a notch from the lower quadrant of at least one lens in each pair of 
eyeglasses. 
4. You may drill a hole in each lens in the wearer's line of sight. 
 
Demonstration lenses that are devices within the meaning of section 201(h) of the act 
and that are offered for sale or distribution to consumers must undergo impact testing 
under 21 CFR 801.410.    
 
Who Should Test and When  
 
20. Q.  Who should perform the test for impact resistance? 
 
  A.  The manufacturer must perform the test for impact resistance (21 CFR 801.410(d)(1)). 
Manufacturer is defined under 21 CFR 820.3(o) and would include the person (or firm) 
who puts the lens in the form ready for its intended use or who alters the physical or 
chemical characteristics of the lens by grinding, heat treating, beveling, applying scratch 
resistant coating, applying anti-reflection coating, cutting, or other pertinent actions. 
Manufactures of all plastic lenses and non-prescription glass lenses may test at the uncut-
finished or finished stage while glass prescription lenses must be tested at the finished 
stage.  Retail laboratories that perform some or all of these processes are manufacturers.  
For the purpose of 21 CFR 801.410, the term "manufacturer" also includes a company 
that imports impact resistant lenses for eyeglasses, or who imports finished eyeglasses or 
sunglasses for resale.  (21 CFR 801.410(g)) 
 
21. Q.  When should lenses be tested for impact resistance? 
 
  A.  You should test lenses when the manufacture and treatments described in Question # 20 
are complete and the lenses are ready to insert into eyeglass or sunglass frames. 
 
22. Q.  Do the impact-resistant lenses regulations apply to lenses manufactured outside the U.S. 
for import into the U.S.? 
 
  A.  Yes. 21 CFR 801.410 applies to all lenses in interstate commerce regardless of their 
origin. 
 
23. Q.  Should retail laboratories perform impact-resistant testing?  
 
  A.  Yes.  Because drilling holes, grinding surfacing, and applying coatings may weaken the 
lens, the retail laboratory should make the lens impact resistant and test the lens before 
delivery to the user.  
 
24. Q.  What is a "Certification Statement of Impact Resistance" and who issues it? 
 
  9  Contains Nonbinding Recommendations 
 
  A.  A "Certification Statement of Impact Resistance" is a written statement from the 
manufacturer guaranteeing that the lenses have been tested and are impact resistant.  
FDA may accept such a certification in lieu of test results, but a manufacturer must 
make the results available, upon request, to the FDA as soon as practicable.  21 CFR 
801.410(g).  Suggested wording can be found in Appendix C.  
 
25. Q.  Can a third-party laboratory test the lenses?  
 
  A.  Yes.  The third-party laboratory can conduct the impact test on behalf of the 
manufacturer. The manufacturer, not the third party laboratory, should render the lenses 
in finished form for testing. Although a third-party may conduct the testing,  the 
manufacturer should issue the certification and be named in any certification issued to it 
by the third party. 
 
Testing Apparatus and Procedure 
 
26. Q.  Does FDA prefer a particular method for making eyeglass lenses impact resistant? 
 
  A.  No.  FDA has no preference for a particular method.  You may use any method, provided 
that the lenses pass the referee test or an equal or superior test. 21 CFR 801.410(d)(1). 
 
27. Q.  What is the "Referee" or "Drop Ball" test and how is it done? 
 
  A.  The terms referee test, drop ball test, and impact test are similar.  The test described in 
21 CFR 801.410(d)(2) is commonly called the drop ball or impact test.  We use the term 
"referee test" when we perform the test to determine compliance with the regulation. 21 
CFR 801.410(d)(1). 
 
    The regulation at 21 CFR 801.410(d)(2) describes the exact procedure for the impact 
test (See Appendix A). The regulation states, In the impact test, a 5/8-inch steel ball 
weighing approximately 0.56 ounce is dropped from a height of 50 inches upon the 
horizontal upper surface of the lens.  The ball shall strike within a 5/8 inch diameter 
circle located at the geometric center of the lens. The ball may be guided but not 
restricted in its fall by being dropped through a tube extending to within approximately 4 
inches of the lens.  To pass the test, the lens must not fracture.... 
 
28. Q.  What constitutes failure to pass the impact test? That is, when is the lens not impact 
resistant (fractured)? 
 
  A.  A lens is fractured and not considered impact resistant if (21 CFR 801.410(d)(2)): 
 
  1.  it cracks through its entire thickness, including a laminar layer, if any, and across a 
complete diameter into two or more separate pieces; or  
  
  10  Contains Nonbinding Recommendations 
 
  2.  any lens material visible to the naked eye becomes detached from the ocular surface 
(i.e., the surface of the lens that is closest to the eye when the lens is in actual use). 
 
If a laminated lens has a crack only through to the lamina and does not disturb the other 
side of the lens, we do not consider the crack to be through the entire thickness and the 
lens passes the test. 
 
29. Q.  Does the apparatus that FDA uses in the referee test have a tube to guide the steel ball as 
it falls toward the lens? 
   
  A.  Yes.  The ball may be guided with a tube that does not restrict its fall while dropping.  
The bottom of the tube must end within approximately 4 inches of the lens (21 CFR 
801.410(d)(2)). Although you may use a guide tube, it is not necessary. 
 
30. Q.  Can the firm modify its referee apparatus to meet the weight specification? 
 
  A.  Yes. The total weight of the base plate and its rigidly attached fixtures cannot be less 
than 27 pounds (21 CFR 801.410(d)(2)).  You may use a heavier base plate or make a 
modification, such as attaching the base plate to a work bench or table so that the bench 
or table is an integral part of the support system or the apparatus itself.  The apparatus 
you use to test the lenses should have a solid support system.  FDA will use test fixtures 
weighing more than 27 pounds. 
 
31. Q.  Should a neoprene gasket be securely bonded to the support tube? 
 
  A.  Yes. The test must be conducted with the lens supported by a tube affixed to a rigid iron 
or steel base plate. 21 CFR 801.410(d)(2). The support tube must be 1-inch inside 
diameter, 1 1/4-inch outside diameter, and approximately 1-inch high and made of rigid 
acrylic plastic, steel, or other suitable substance.  A neoprene gasket must be securely 
bonded on the top edge of the support tube.  The neoprene gasket must be 1/8- by 1/8-
inch in size and have a hardness of 40 +/-5, a minimum tensile strength of 1,200 pounds, 
and a minimum ultimate elongation of 400 percent (21 CFR 801.410(d)(2)).  See 
Appendix B for a photograph of the test apparatus. 
 
32. Q. Can a manufacturer secure the lens in the testing apparatus to prevent lens movement or 
repeated impact with the ball? 
 
 A.  FDA does not secure the lens during FDA testing and the regulation contains no 
provisions for securing the lens.  However, you may use measures to protect the lens 
from damage during testing, as long as these measures do not interfere with the validity 
of the test results.   
 
33. Q.  How can manufacturers of eyeglasses or sunglasses test laminated lenses for impact 
resistance? 
 
  11  Contains Nonbinding Recommendations 
 
  A.  You may drop ball test laminated eyeglasses or sunglasses individually or on the same 
statistical basis as plastic lenses, unless they are of a type unsuitable for impact testing, 
as specified under 21 CFR 801.410(c)(3). See Question # 43 for exempt lenses. 
 
34. Q.  Should manufacturers test plastic lenses in a variety of thicknesses? 
 
  A.  Yes.  Manufacturers should test plastic lenses using a statistically significant sampling of 
lenses from each production batch.  The regulation at 21 CFR 801.410(c)(3) states,  
All non-prescription lenses and plastic prescription lenses tested on the basis of 
statistical significance shall be tested in uncut-finished or finished form.  In practice, 
this means that manufacturers who sell semi-finished lenses or lens blanks to optical 
laboratories or other processors should take the following steps: (1) Tell these customers 
the degree of thickness at which the lenses were tested, and (2) caution them to test each 
lens that is further processed to a thickness less than this minimal level. 
 
35. Q.  Can the manufacturer use tests other than the referee test to demonstrate impact 
resistance? 
 
  A.  Yes.  The manufacturer must conduct tests of lenses using the impact test in 21 CFR 
801.410(d)(2) (referee test) or any equal or superior test.  21 CFR 801.410(d)(1).  The 
manufacturer should maintain appropriate records to demonstrate that the alternate 
method is equal or superior to the referee test. The FDA does not need to pre-approve an 
alternate testing method. FDA, however, will use the referee test when it is testing lenses. 
 
Sampling Plans 
 
36. Q.  What constitutes a "batch"?  
  
  A.  The regulation requires testing of all non-prescription lenses and plastic prescription 
lenses on a "statistically significant sampling of lenses from each production batch (21 
CFR 801.410(c)(3)).  The regulation allows each manufacturer to define what 
constitutes a batch for its operation. A batch should be a recognizable or identifiable 
entity, and the manufacturer must maintain appropriate records of batch testing. 21 CFR 
801.410(f). When feasible, a batch represents a product quantity, which is similar in 
nature, given process variation, and can also be quarantined if drop ball test results show 
the batch has failed.  In certain circumstances, it may be impossible to define a batch 
based upon uniform characteristics.  For manufacturers who produce a large variety of 
individually prescribed lenses, each with varying characteristics, a batch size may be 
defined as a day or a week of production.  For these manufacturers, the testing sample 
should contain appropriate proportions of the combinations of the different lens materials 
and coating so that it is representative of the entire batch.   
 
37. Q.  What type of sampling methods may manufacturers use to obtain a "statistically 
significant" sample of lenses? 
 
  12  Contains Nonbinding Recommendations 
 
  A.  FDA does not limit manufacturers to any specific sampling plan; however, you should 
use a valid statistical sampling plan.  FDA has recognized the standards below.  You 
may use either of these standards or an equivalent standard.   
 
ANSI/ASQC Z1.4/1993, Sampling Procedures and Tables for Inspection by Attributes  
American National Standard Institute (ANSI) 
http://www.ansi.org  
 
American Society for Quality (formerly America Society for Quality Control 
(ASQC) 
http://www.asq.org  
 
ISO 2859-1/1999, Sampling Procedures for Inspection by Attributes -- Part 1: Sampling 
Schemes Indexed by Acceptance Quality Limit (AQL) for Lot-by-Lot Inspection 
International Organization for Standardization (ISO) 
http://www.iso.ch  
 
CDRH supplemental information for these standards is available at 
www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/search.cfm or directly at 
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/Detail.CFM?STANDAR
D__IDENTIFICATION_NO=1595 and 
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfStandards/Detail.CFM?STANDAR
D__IDENTIFICATION_NO=1585 for the ISO or ANSI document, respectively. 
 
You can find information on how to purchase these standards by contacting the standards 
organization. 
 
FDA will also accept the use of Military Standard 105E (MIL-STD 105E), May 10, 
1989, "Sampling Procedures and Tables for Inspection by Attributes" at an Acceptable 
Quality Level (AQL) of 6.5, General Inspection Level II.   
 
38. Q.  If an optical wholesale laboratory or retail laboratory has multiple locations that use the 
same procedures and equipment, can testing lenses from one location for impact testing 
cover all locations for compliance with the regulation? 
 
  A.  No.  There may be subtle process differences at different locations that can affect the 
impact resistance of a lens (e.g., wear on a diamond wheel used in surfacing, age of 
polish, age of coatings, experience of operators). You must test statistically significant 
samples of each batch of nonprescription lenses and each batch of plastic prescription 
lenses as well as each glass prescription lens individually. 21 CFR 801.410(d)). 
  
39. Q.  If finished lenses fail impact testing, even when processed in accordance with the original 
manufacturer's recommendations, should the wholesale laboratory or retail laboratory 
notify the original lens manufacturer? 
 
  A.  Manufacturers should manufacture and process lenses in accordance with the Quality 
System regulation under 21 CFR 820.  If repeated failures occur, the wholesale 
  13  Contains Nonbinding Recommendations 
 
laboratory or retail laboratory should evaluate its processes to assure its processes are in 
control.  If repeated failures continue, the laboratory should notify the original lens 
manufacturer. 
 
Records 
 
40. Q.  What are the recordkeeping requirements for those persons conducting impact resistant 
testing under 21 CFR 801.410(d)?  
  
  A.  Such persons must maintain the results of the testing, a description of the test method, 
and of the test apparatus for 3 years.   21 CFR 801.410(f).
  
 
41. Q.  What records are manufacturers required to maintain?  
 
  A.  Manufacturers are required to maintain the records referenced previously (Question 
#40).  In addition, the manufacturer must maintain copies of invoices(s), shipping 
documents, and records of sale or distribution of all impact-resistant lenses, including 
finished eyeglasses and sunglasses for three years (21 CFR 801.410(e)).   
 
42. Q.  What information is the retailer required to keep on individuals purchasing eyeglasses or 
sunglasses? 
  
   A.  There are no requirements for the retailer to keep and maintain the names and addresses 
of individuals purchasing nonprescription eyeglasses and sunglasses at the retail level 
under 21 CFR 801.410.  However, the retailer should consult state law to determine 
relevant state requirements for the sale of prescription lenses.  
 
Exemptions 
 
43. Q.  What lenses are exempt from the impact test? 
 
  A.  The following special lenses must be impact resistant but are exempt from testing:  
Raised multifocal lenses shall be impact resistant but need not be tested beyond initial 
design testing.  Prism segment multifocal, slab-off prism, lenticular cataract, iseikonic, 
depressed segment one-piece multifocal, bioconcave, myodisc and minus lenticular, 
custom laminate and cemented assembly lenses shall be impact resistant but need not be 
subjected to impact testing. (21 CFR 801.410(c)(3))  
 
Importing Lenses, Eyeglasses, and Sunglasses 
 
44. Q.  What should be submitted to the FDA at the U.S. Port of Entry? 
 
  14  Contains Nonbinding Recommendations 
 
  A.  Nearly all commercial entries come to FDA through the U.S. Customs and Border 
Protections Automated Broker Interface (ABI) system submitted by a customs 
brokerage firm (or filer).  FDA processes these entries electronically in its Operational 
and Administrative System for Import Support (OASIS) system.   
To streamline the entry process, we recommend that you use the affirmation of 
compliance code, IRC, for electronic entries or submit a "Certification Statement of 
Impact Resistance." (See Q #24).  We provide suggested wording for a certification 
statement in Appendix C.    
 
If the lenses are manufactured outside the U.S., the foreign manufacturer should test the 
lenses prior to exporting to the U.S.  The foreign manufacturer should provide a 
certification of impact resistance with the shipment of finished lenses that requires no 
further processing, except for being inserted into a frame.   
 
If you import semi-finished prescription or non-prescription lenses into the U.S., you 
should label the lenses, "Requires further processing, not a finished device. Semi-
finished lenses require further processing.  Under these circumstances, the U.S. finished 
device manufacturer is responsible for performing the impact testing.   
 
In addition to the certification statement, FDA reviews information you provide to 
demonstrate that the device meets FDA requirements. This includes registration number, 
device listing number, and U.S. Agent information for prescription spectacle lenses (21 
CFR 886.5844), magnifying spectacles (21 CFR 886.5840), and sunglasses 
(nonprescription) (21 CFR 886.5850). If you are submitting an electronic entry through 
the ABI system, you should provide this information in the affirmation of compliance.  If 
you are not submitting an electronic entry through the ABI system, you should annotate  
this information on U.S. Customs and Border Protections entry declaration form that is 
appropriate for the type of entry and provide a copy to the FDA district office at the port 
of entry. 
 
45. Q.  What are FDAs processes for inspection and/or sampling for testing of a shipment of 
lenses or sunglasses? 
 
  A.  Ophthalmic devices are subject to inspection and/or sampling by the FDA as part of 
FDA's efforts to determine the device's compliance with the act.  FDA does not inspect 
every import entry. FDA may request additional information or documentation, such as 
records of impact testing results, or request to examine the shipment. If FDA chooses to 
collect a sample, the District Office typically notifies the import broker (or filer),  the 
owner or consignee, and importer of record (if different than owner or consignee) of its 
intent to sample.  
FDA provides official notification of the entry reviewer's decision to sample by 
submitting a "Notice of FDA Action" sampling request.  
 
Once FDA has been advised of the location and the availability of articles, the FDA 
personnel will visit the site to perform the examination and/or sample collection.  FDA's 
examination of the entry and sample collection cannot proceed until the agency receives 
the "notification of availability."  After collection of the sample, FDA typically provides 
  15  Contains Nonbinding Recommendations 
 
an additional "Notice of FDA Action" detailing the articles and amounts collected.   If 
the article is found to be in compliance after examination, the filer, importer of record, 
consignee, and the U.S. Customs and Border Protection (CBP) are notified by Notice of 
Release that the article may be admitted as far as FDA is concerned. 
 
46. Q.  If FDA tests the shipment at the port of entry, how many lenses are tested? 
  
  A.  FDA will test a statistically significant sample size in order to determine compliance with 
the FDA impact test regulation.  The sample size will depend on the size of the shipment 
that FDA is testing. 
 
47. Q.  What does the FDA testing lab do with sunglasses/eyeglasses after being tested?   
 
  A.   Samples that are damaged are no longer suitable for use and are not returned to the 
importer.  If requests are made to a District Office for the return of any non-damaged 
samples, FDA tries to comply with the requests.   
 
48. Q.  What should I do if my shipment is refused admission? 
 
A.  FDA may issue a Notice of Detention and Hearing to refuse admission of a shipment 
if the device appears to be in violation of section 801(a) of the act (21 U.S.C. 381(a)).  
FDA issues the "Notice of Detention and Hearing" detention to the broker (or filer), 
importer of record, and the owner or consignee, where applicable. The notice will specify 
the nature of the violation charged and will designate the place and period of time during 
which the owner or consignee (or authorized representative) can provide oral or written 
testimony as to the admissibility of the article.  
 
You will find additional information on FDA import procedures in FDAs Regulatory 
Procedures Manual, Chapter 9 Import Operations/Actions available at 
http://www.fda.gov/ICECI/ComplianceManuals/RegulatoryProceduresManual/ucm179
264.htm 
 
If you have questions regarding the detention or would like to discuss how to bring the 
devices into compliance, you should contact the FDA District Office at the port of entry.  
The FDA District Office directory is available on the Internet at 
http://www.fda.gov/ICECI/Inspections/IOM/ucm124008.htm. 
 
49. Q.  Is the importer required to report adverse events to FDA and to the manufacturer? 
 
  A.  Yes.  Under the Medical Device Reporting regulations (21 CFR 803), importers must 
report to FDA and provide a copy of the report to the manufacturer if one of the 
importers marketed devices may have caused or contributed to a death or serious injury. 
21 CFR 803.40.  Such report must be submitted as soon as practicable, but not later than 
30 days after the importer receives or otherwise becomes aware from any source of such 
information. Similarly, the importer must report to the manufacturer if one of the devices 
marketed by the importer has malfunctioned and such device or a similar device 
marketed by the importer would be likely to cause or contribute to a death or serious 
  16  Contains Nonbinding Recommendations 
 
injury if the malfunction were to recur. 21 CFR 803.40. The report must be submitted 
on Medwatch Form 3500A, 21 CFR 803.40.  You can find additional information on 
Medical Device Reporting at 
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/default.htm.  
 
Optical Laboratories and Retail Stores 
 
50. Q.  Are there regulatory requirements for optical laboratories that surface (optically shape 
lens) perform edge cutting, or cast/mold lenses to a specific individual prescription?  
 
 
  A.  U.S. optical laboratories that meet the definition of manufacturer must comply with all 
applicable provisions of the Federal Food Drug & Cosmetic Act. However those 
laboratories whose major responsibility is to render a service necessary to provide the 
consumer with a device or the benefits to be derived from the use of a device are exempt 
from registration under 21 CFR 807.65(i).  Foreign optical laboratories, however, are 
not exempt from registration under 21 CFR 807.65.  21 U.S.C. 807.40.  Foreign optical 
laboratories must submit an Establishment Registration and Device Listing (21 CFR 
807.40(a) and 807.22) using FDAs Unified Registration and Listing System (FURLS).  
Foreign manufacturers must also provide the name, address, and phone number of their 
U.S. Agent (21 CFR 807.40(b)).  Instructions on how to register, list and information 
about U.S Agent requirements are available on the Internet at: 
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYour
Device/RegistrationandListing/default.htm.   
 
All manufacturers (as referenced in Question #21) of impact resistant lenses for 
eyeglasses or sunglasses and of finished eyeglasses or sunglasses, including importers of 
such lenses and glasses, must follow the Quality System regulation (21 CFR 820) and 
report adverse events under Medical Device Reporting (21 CFR 803).  Optical 
laboratories are exempt from Medical Device Reporting under 21 CFR 803.19(a)(3).  
 
51. Q.  Do the impact test regulations apply to retail stores that fabricate lenses? 
 
  A.  FDA considers retail stores that fabricate lenses by coating and/or surfacing to be 
manufacturers of impact-resistant lenses.  Therefore, such retailers must document 
impact resistance (21 CFR 801.410(c)(3)).  You may perform impact testing on site or 
you may contract with a third party testing lab.  Retail stores that only perform edging 
are not considered manufacturers. 
Dispensing Untested Lenses 
 
52. Q.  Under what circumstances may retailers dispense lenses that are not impact resistant? 
 
  A.  You may dispense lenses that are not impact resistant when a physician or optometrist 
determines that impact-resistant lenses will not fulfill the visual requirements of a 
  17  Contains Nonbinding Recommendations 
 
particular patient.  The physician or optometrist must direct this in writing and give 
written notification to the patient (21 CFR 801.410(c)(1)). 
 
53. Q.  May a retailer supply a nonimpact-resistant lens if a patient requests it or if the 
patient/customer agrees to assume all responsibility? 
 
  A.  You may only provide nonimpact-resistant lenses when the physician or optometrist 
determines that impact-resistant lenses will not fulfill the visual requirements of the 
patient.  In such cases, the physician or optometrist must give notice in writing to the 
patient, explaining that the patient is receiving a lens that is not impact resistant. 21 CFR 
801.410(c)(1). 
 
54. Q. What are some reasons a physician or optometrist may prescribe nonimpact-resistant  
            lenses for a patient?  
 
  A.  Physicians or optometrists may invoke the special exemption provisions of the regulation 
based on professional judgment.  For example, a patient's prescription cannot be filled by 
impact-resistant lenses because the physician or optometrist knows from previous 
experience that the weight of the heavy lenses may cause headaches, undue pressure on 
the bridge of the nose or ears, and pressure sores.  The physician or optometrist may 
determine that the visual requirements of the patient cannot be met by use of impact-
resistant lenses.    
 
55. Q.  Are there situations in which a retailer may provide nonimpact-resistant lenses? 
 
  A.  FDA believes it is appropriate to exercise  its enforcement discretion with respect to a 
retailer who provides nonimpact-resistant lenses in an emergency situation  with the 
knowledge and consent of the patient and the eye care professional.  For example, a 
surgeon's eyeglasses break just before a scheduled surgery and the lenses need to be 
replaced immediately.  If there is no alternative, FDA would consider exercising 
enforcement discretion with respect to a retailer who may provide the surgeon with 
nonimpact-resistant lenses on a temporary basis with the knowledge and consent of the 
patient and eye care professional. 
Frames and Designs 
 
56. Q.  What are the FDAs requirements for the physical properties of lenses or the design of 
             lenses? 
 
  A.  The regulation requires only that lenses be made impact resistant and are impact tested.  
FDA has no other device specific property or design requirements imposed on lenses by 
regulation. 
 
57. Q.  Are there additional requirements for rimless eyewear? 
 
  18  Contains Nonbinding Recommendations 
 
  A.  No.  Rimless eyewear must meet the same requirements as framed eyewear, including 
impact testing.  
 
58. Q.  What are the FDA regulations for spectacle frames? 
 
  A.  A spectacle frame is a device made of metal or plastic intended to hold prescription 
spectacle lenses worn by a patient to correct refractive errors.  Spectacle frames are 
regulated as Class I medical devices classified under 21 CFR 886.5842.  They are 
exempt from Premarket Notification (510(k)).  You can find the regulatory requirements 
for spectacle frames in Sunglasses, Spectacle Frames, Spectacle Lens and Magnifying 
Spectacles 21 CFR 886.5842 - 886.5850. 
 
Labeling
 
 
59. Q.  What are the labeling requirements for sunglasses or eyeglasses?  
     
  A.  General labeling requirements can be found in 21 CFR 801.1 - 801.16 and can be 
accessed on the Internet at: 
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/showCFR.cfm?CFRPart=801.  
 
60. Q.  Can labeling for sunglasses or eyeglasses include the terms shatterproof or shatter-
resistant?  
     
  A.  Yes, provided that such a claim is truthful and not misleading and meets all regulatory 
and statutory requirements for labeling and Premarket Notification. The terms 
shatterproof or shatter-resistant are not equivalent to the term impact resistant.  
Lenses that pass impact testing may be labeled as impact resistant.  Impact-resistant 
lenses may break or shatter under certain conditions.  Impact-resistant testing does not 
demonstrate that the lens is either shatterproof or shatter-resistant.  The manufacturer, 
therefore, should not make labeling claims such as shatterproof or shatter-resistant 
based solely on impact testing. 
 
Additional Regulatory Requirements 
 
61. Q.  When would a Premarket Notification 510(k) be required for lenses or sunglasses?  
 
  A.  Nonprescription sunglasses (21 CFR 886.5850), prescription spectacle lenses (21 CFR 
886.5844), and magnifying spectacles (21 CFR 886.5840) are Class I devices and 
exempt from Premarket Notification 510(k).  However, a 510(k) would be required if 
the device falls outside the limitations of the exemption (21 CFR 886.9).  FDA would 
consider changes that could significantly impact safety or performance or that constitute 
a new intended use to be outside the limitations of the exemption, and thus, a submission 
of a 510(k) notification would be required.  
  19  Contains Nonbinding Recommendations 
 
 
You should submit a 510(k) when you have a health-related claim or performance-
related claim that has not previously been cleared by FDA in a 510(k).  The following 
are examples of the type of health-related claims that could require the submission of a 
510(k):  protects against the formation of cataracts, prevents cataracts and other ocular 
disorders, improves visual acuity, or treats color blindness.  An example of a 
performance-related claim that could require a 510(k) is labeling that the lenses are 
shatterproof.  FDA would consider such statements as claims that go beyond those 
made by exempted legally marketed devices of that generic type.   
 
Consumer Information 
 
62. Q.  Are eyeglasses and sunglasses safe to use for sports? 
 
  A.  No.  You should wear sports goggles that meet appropriate safety standards for the sport.  
You should not wear sunglasses or eyeglasses as personal protective equipment for 
sports or in situations requiring industrial safety lenses that could result in an impact to 
the face.  
 
63. Q.  Where can consumers report serious injuries related to medical devices? 
   
A.  Consumers may voluntarily report device-related deaths, injuries, and product problems 
to the Medical Device Reporting Office (MEDWATCH) of FDA.  Consumers should use 
the MedWatch FDA Voluntary Form 3500 available on the Internet at 
http://www.fda.gov/Safety/MedWatch/default.htm to report problems.  For information 
about a medical product, please call 1-888-INFO-FDA (1-888-463-6332).  Written 
correspondence may be mailed to: 
     
MedWatch 
5600 Fishers Lane 
Rockville, MD  20852-9787 
 
APPENDIX A.   
21 CFR  801.410  Use of impact-resistant lenses in eyeglasses and sunglasses.  
http://frwebgate.access.gpo.gov/cgi-bin/get-
cfr.cgi?TITLE=21&PART=801&SECTION=410&TYPE=TEXT 
 
APPENDIX B.  
Drop Ball Test Unit (Impact Tester) 
http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocumen
ts/ucm150003.htm 
 
APPENDIX C.   
Certification Statement of Impact Resistance  
  20  Contains Nonbinding Recommendations 
 
http://www.fda.gov/downloads/MedicalDevices/DeviceRegulationandGuidance/Guidan
ceDocuments/ucm095296.pdf   
 
  21