The answer will depend on whether the Hearing Loss Association of America is a qualified charitable organization and whether you attended the convention as a selected delegate.
IRS Publication 526 Charitable Contributions says this about attending conventions:
If a qualified organization selects you to attend a convention as its representative, you can deduct your unreimbursed expenses for travel, including reasonable amounts for meals and lodging, while away from home overnight for the convention.
You can't deduct personal expenses for sightseeing, fishing parties, theater tickets, or nightclubs. You also can't deduct travel, meals and lodging, and other expenses for your spouse or children.
You can't deduct your travel expenses in attending a church convention if you go only as a member of your church rather than as a chosen representative. You can, however, deduct unreimbursed expenses that are directly connected with giving services for your church during the convention.
Thank you. What if you are not an employee? I am a board member of a chapter of the Hearing Loss Association of America. While at the convention, I lined up speakers and collected information on new tech developments, all of which I brought back to the chapter. If this is permissible, where would I enter this on TurboTax? Thank you.
You don't have to be an employee of the organization; just it's designated representative at the convention.
Enter your travel expenses under Deductions & Credits > Charitable Donations > Mileage and Travel Expenses.
This is reported on Schedule A for Itemized Deductions.
Here's more info from the IRS on Charity-Related Travel.