Those new to the field might think that interviewing a candidate for a job would be a straightforward task: ask candidates questions, get answers and make a hiring recommendation or decision.

But HR and hiring managers must be careful to ask the right questions, and avoid those that are off limits. Questions that would be fine among casual acquaintances often are inappropriate for a job interview; conversely, those who look to avoid a mistake may hesitate to probe subjects that should be discussed.

So where's the middle ground? Experts who spoke with HR Dive helped to create a concrete list of guidelines that can help you get the information you need without exposing you — and/or your organization — to legal risk.

Know which topics are off limits

Some questions should obviously be avoided, Jeffrey Beemer, business lawyer at Dickinson Wright, told HR Dive. These are questions that ask directly or indirectly about protected classes including age, race, ethnicity, gender, national origin, marital status and disability status.

"Questions that are asked in an interview don't necessarily violate the law in and of themselves," Beemer said. "The problem is when an employer asks about an applicant's membership in a protected class or that would lead to the discovery of whether someone is in a protected class." If the applicant is then not hired, she can say that information was used in a discriminatory way, Beemer said.

While it's a simple concept, the execution can be trickier, especially when the intent is not to violate discrimination laws, but to build a rapport with a candidate.

If a candidate appears obviously pregnant, for example, a natural instinct might be to ask when she's due. Or if someone has an interesting accent, it may be tempting to ask where they are from — but don't, said Jenn Betts, employment attorney at Ogletree Deakins. "It's human nature to want to be friendly and build a connection, but part of being an HR professional is recognizing what is and what is not an appropriate thing to say," she said.

Avoid the unnecessary questions

While few applications still ask an applicant's age, many still get an approximation by asking the applicant when they graduated from college. While this is not an obvious age question, it still solicits information that is protected, and therefore should be avoided, Betts said. It also does not provide information that is useful in assessing the candidate's qualification for the job.

Likewise, salary history questions have long been used to determine whether a candidate's previous salary was in range for a given job. But research showing that this practice may perpetuate gender and racial pay gaps has prompted a growing list of states and localities to ban such questions. What's more, not all state and local laws are uniform in spelling out what employers can ask and how they can use the information. Given this picture, Betts said, HR professionals should focus on salary expectations instead.

Ask the sticky 'accommodation' questions

Newer HR professionals may worry they can't ask any personal questions, yet it is sometimes their responsibility to do so. One area that can make interviewers uneasy is disability accommodations.

Interviewers can ask a candidate about accommodation, but it's how you do it that is key, Sarah Riskin, labor and employment attorney for Nilan Johnson Lewis, told HR Dive. If you're interviewing for a job that requires using heavy machinery and a candidate has an obvious physical disability, you can ask specific questions, she said; "You can ask about an essential function."

For example, an interviewer could say, "An essential function of the job is X. Are you able to do that with or without a reasonable accommodation?"

Riskin said she advises interviewers not to ask about the disability itself or why an accommodation is needed, but to focus on the candidate's ability to perform the job.

Interviewers should be asking all candidates the same questions for consistency, Riskin said. But interviewers also do not have to ignore an obvious disability that could prevent an individual from performing the essential functions of a job. "As a matter of federal law — and every state could be different — if there's an obvious disability that makes you question if someone can do the job, you're entitled to ask specifically to make sure they can do the job," she said.

Sidestep interviewing minefields

Even if an HR professional diligently focuses on keeping an interview on track, a candidate can inadvertently steer the conversation off the rails. Suppose, for example, the interviewer asks, for job-related reasons, whether or not the candidate speaks another language. The candidate not only answers the question, but describes how she learned the language, how she grew up in a certain country, or perhaps her experience moving to the U.S.

Because this information could tap into an existing bias, it is important to redirect quickly, Riskin said. Interviewers can pivot, saying, "That's really interesting. I'm glad you speak that language. Let's talk more about the other requirements of the job," she suggested.

Maintain accurate, updated job descriptions

The ability to ask job-focused questions relies on having accurate and updated job descriptions, Betts said. Some companies have outdated job descriptions that have little to do with the current requirements of the job. To be safe, make sure the description is for what the position is really doing, Betts said.

In creating these job descriptions, hone in on essential job functions. If the job requires that candidates be able to stand for six hours, lift 20 pounds or other tasks, include them. And if it doesn't truly require those tasks, they should be excluded. Then, when you look at the job description alongside your interview questions, you can ask yourself:

• What is the purpose of each question?
• Is there underlying information I'm trying to get and, if so, can I ask for it directly?
• Does the question provide information on the candidate's ability to complete an essential job function?

This review will help new and experienced interviewers avoid the questions they shouldn't ask and tackle the ones they should, Beemer said. "The trained HR professionals don't get squeamish. They are well-prepared and have a plan of how they're going to cover [these issues] with all applicants during the interview process."