Interviewers introduced the questions on firearm safety by stating, "The next questions are about safety and firearms. Firearms include pistols, shotguns, rifles, and other types of guns. Do not include guns that cannot fire, starter pistols, or BB guns." The survey form also directed interviewers to read if necessary: "Sometimes the use of firearms can lead to injury, which is a health problem."

IPUMS NHIS recoded responses were created from a cascade of 5 questions (asked based on the response to a prior question) to indicate if:

• "1," no ammunition was stored in home

• "2" if all the ammunition was stored apart from the gun in a locked place

• "3" if some ammunition was stored with the gun in an unlocked place

If the respondent asked for clarification of the questions about ammunition storage, the Field Representative's Manual further instructed interviewers to, "Explain that this includes any ammunition, not just that specific to the firearm(s) kept at home."