Figure 3-1 Logical sequence of banknote verification: recognition-denomination-authentication.

It is instructive to describe the "ideal" feature for recognizing; denominating; and, if possible, authenticating banknotes as a model to compare with "real" features. The committee gained some insight by summarizing the attributes of an ideal counterfeit-deterrent feature as they were described in previous reports (NRC, 1993; Church and Littman, 1992). These attributes are as follows:

• difficult to duplicate;

• difficult to simulate;

• easily recognized by the general public;

• durable (i.e., the feature is useful even after considerable wear);

• easy to produce at low cost;

• can cocirculate with current banknotes;

• acceptable to the public (aesthetically pleasing);

• machine readable; and

• nontoxic and nonhazardous.

While the previous NRC study concentrated on optical or visible features to deter counterfeiting (NRC, 1993), many of these attributes are also desirable in a feature to be used by visually disabled people to recognize and denominate U.S. banknotes. An ideal feature for visually disabled people would also

• reliably indicate the denomination of the banknote;

• reliably indicate the orientation of the banknote;

• address the needs of the whole population, from blind people to the normally sighted; and

• be easy to use (i.e., not require a device or extended handling).

The list of features to evaluate was very long, and each feature had several variations. In the present study to evaluate and compare a disparate group of possible features, the committee took a similar approach to that taken in the consideration of counterfeit-deterrent currency features. That is, the committee identified a set of requirements that may be stated initially in vague or general terms, converted the requirements into indicators or criteria; weighted the criteria in terms of their relative importance; and scored or ranked the alternatives with reference to the criteria.

In addition to the purely "technical" evaluation described above, the committee considered the target populations for the individual features. A feature that might be of considerable assistance to those with normal or low vision might not benefit blind people at all. Since there may be a relatively large population that would benefit from the feature, the committee chose to recommend that feature despite the fact that it would not be universally useful. The committee also considered features that may be of principal benefit to people who are blind, which might not be particularly useful to those with some vision. The committee attempted to ensure that their list of recommended features provided overlapping coverage, so that each of the target groups would gain significant benefits from the redesigned banknotes if those recommended features were included.

Figure 3-2 Evaluation criteria used to determine the effectiveness of proposed currency features.

For example, punching holes in banknotes, with the number of holes indicating denomination, would be assessed as a general concept in the technical success probability category, with some positive and some negative attributes. In the implementation success criteria category, the shape of the hole (for example, star-shaped, round, or oval) would need to be known for evaluation against criteria such as feature survivability or note durability. The committee's assumption about how a particular feature would be implemented was noted when the feature was evaluated. The various ways a feature could be implemented are discussed in chapters 4 and 6.

The committee gave more weight to certain criteria in each category. In the first category, features that would be useful to people who are blind and those with low vision were given more weight. In the function category, the major weight was placed on denomination, as opposed to authentication, recognition, or orientation. Authentication (in the committee's strict definition) is not thought to be more of a problem for visually disabled people than for the rest of the population, but features that could be used for authentication as well as denomination were rated more highly than features that were only useful for denomination. Orientation of banknotes is necessary for many vending machines and for bank deposits (mostly from businesses, where large amounts of cash are regularly brought into the bank), so it is included as a desirable attribute but not an essential one.

In the final two categories, technical success risk and implementation success risk, the criteria were not strictly ranked but were thought of as "high" weight or "low" weight. In the category for technical success criteria, the criteria considered to be most important were

• reliability of readings;

• ease of use;

• compatibility with security features;

• no requirement for a device other than a person's senses; and

• resistance to simulation.

Table 3-1 Population Category

______________________________________________________________________________________
Category                                Description of a Successful Feature           
______________________________________________________________________________________

Blind                                   Blind people can use the feature              

Low Vision                              People with low vision can use the feature    

Normally Sighted, Adverse Lighting      Normally sighted people can use the feature   
                                        in low light                                  

Normally Sighted, Normal Lighting       Normally sighted people can use the feature   
                                        in normal light                               
______________________________________________________________________________________

Table 3-2 Function Category

______________________________________________________________________________________
Category           Description of a Successful Feature                                 
______________________________________________________________________________________

Recognition        Feature can be used to differentiate banknotes from other           
                   similar-sized paper                                                 

Denomination       Feature can be used to determine the value of the banknote          

Authentication     Feature can be used to determine if the note is a genuine U.S.      
                   banknote                                                            

Orientation        Feature can be used to orient banknotes for use in vending and      
                   other machines                                                      
______________________________________________________________________________________

Table 3-3 Technical Success Criteria

______________________________________________________________________________________
Category                      Description of a Successful Feature 
______________________________________________________________________________________

Reliability of Readings       Readings do not give "false positives," (i.e., they do 
                              not indicate that a note is a denomination other than its
                              true value) or "false negatives" (reject valid banknotes)
                                               
Ease of Use                   Feature is easy to use, especially in a situation        
                              where there is little time to examine money 
             
No Requirement for Device     A person's senses can be used to evaluate the            
                              banknote, with no requirement for any device or machine  

Applicability to Current      Feature could be applied to currency presently in        
Banknotes                     circulation or production without a redesign             

Compatible with Security      Feature is compatible with security features scheduled   
Features                      for implementation in the new currency design or         
                              recommended in the previous report (NRC, 1993)           

Ability to Cocirculate        Notes can cocirculate with present notes without         
                              confusion, misidentification or compromise of            
                              automated money-handling machines                        

Resistance to Simulation      Feature cannot be easily simulated or corrupted to       
                              indicate another denomination                            
______________________________________________________________________________________

Table 3-4 Implementation Success Criteria

______________________________________________________________________________________
Category                      Description of a Successful Feature                     
______________________________________________________________________________________

Unit Cost                     Unit cost for note production (cost per note) is low    

Capital Cost                  Capital cost to BEP and Federal Reserve is low          

Durability of Banknote        The feature will not significantly reduce durability    
                              below that of present banknotes                         

Survivability of Feature      Feature will serve its intended use after wear and      
                              tear of handling and circulation                       

Availability and              Technology to manufacture banknotes with the feature    
Manufacturability             is available now                                       
 
Proven Banknote Technology    Feature has been used before on banknotes in other      
                              countries                                               
______________________________________________________________________________________

In the category for implementation success criteria, the most important criteria were

• survivability of the feature;

• durability of the banknote;

• capital cost; and

• availability and manufacturability.

Capital costs were considered too high at the point where a complete line of additional printing equipment would be required. A new line of equipment may also have an impact on unit costs. Changes to existing operating equipment or modifications to parts of the equipment were considered to be acceptable in terms of capital and unit costs.

The list of proposed features was organized generally into groups, including substrate based, edge modification, tactile marking, visual marking, and other. The proposed features were evaluated against the criteria described in these tables, using a "yes," "no," or "maybe" to indicate whether the feature met each criterion for success, whether it did not meet the criterion, or whether the committee was not able to evaluate whether the proposed feature met the criterion. For the cost criterion, the full costs of implementation, including costs beyond those incurred by the BEP, were considered to be outside the scope of the present work. The ideal feature for use by visually disabled people would have been rated "yes" in all categories.

If a feature was evaluated a no or a maybe for a certain criterion, the committee discussed whether the shortcoming of that feature was a fundamental limitation of the feature or whether the technology required for the feature to be useful and realizable could benefit from further development work. Features that fit into the latter category were noted as candidates for future research (see Chapter 5). Compatibility with security features may be highly important for the near term. Incompatibility with security features proposed for implementation in the long term is not as serious a negative factor, since research and development work to be done for the security feature may determine a way to improve compatibility.

Further criteria were needed for any feature that required the use of a device for denominating banknotes. Some features, while not accessible to a person's unaided senses, may make it easier to design a simple and convenient device to denominate banknotes. This type of device could have widespread use in the vending community and may be necessary for those who cannot use other features implemented. Features in this category will be evaluated in Chapter 4, along with features that allow for unaided banknote denomination. The types of devices that the committee envisions will be developed are also discussed in Chapter 4. An additional set of criteria was developed for the evaluation of the devices themselves.

When considering the use of devices, the committee identified various criteria that would contribute to successful implementation of a device. In addition, the committee outlined various performance-related criteria that need to be fulfilled when a device is operated in a realistic environment.

The criteria for evaluating devices were the following (in no specific order):

• ability to recognize and denominate;

• highly accurate;

• private;

• small/portable;

• low maintenance;

• inexpensive/good value;

• rapid response;

• low power consumption; and

• long lived.

Future development of denomination devices might emphasize the ability to authenticate banknotes as well as to denominate them. The term "inexpensive" is coupled with "good value" to indicate that the amount that a person would be willing to pay for a device is directly related to how useful that device would be. That is, a small, easily used device might be a good value at a higher price than a larger, slower device. If a device receives a satisfactory rating for all of the above criteria, then its operational characteristics for performance should include:

• a low-false-reject rate;

• independence of note orientation;

• an acceptable operating temperature/humidity range; and

• easy use by untrained/unskilled individuals.

Church, S., and D. Littman. 1992. Presentation by Sara Church, Bureau of Engraving and Printing, and Dan Littman, Federal Reserve System, to the Committee on Next-Generation Currency Design. October 21, 1992.

NRC (National Research Council). 1993. Counterfeit Deterrent Features for the Next-Generation Currency Design. NMAB-472. National Materials Advisory Board, NRC. Washington, D.C.: National Academy Press.