This information is an excerpt from Section C of the January 2024 version of the NHPA Rules/Regulations Guidelines Specifications
The use of hand signals is optional. but very helpful to scorekeepers who may have difficulty hearing verbal calls, for a wide variety of reasons. Though there may be more than one hand signal for some calls, the following are based on written survey results, and from discussions and the recommendations of many scorekeepers.
Calls/Signals for Cancellation Play:
View the entire rule here: (Review Rule 6, Section B.1 – Calling the Score)
Alternate hand signals, for some calls, can be found in Newsline Magazine articles and/or on the NHPA website.