Better awareness of FMLA rules and regulations – and regular training to keep information fresh – is important for HR managers and general managers. Staying on top of common mistakes is key. And, of course, employees should be educated in FMLA's particulars, too. Here are key facts and mistakes to keep in mind.

Top barrier: Complex eligibility requirements

Getting eligibility right is a guard against compliance mistakes.

Eligible employers must have 50 or more employees working each day for at least 20 calendar weeks over the previous 12 months or current calendar year at the time a leave is requested. This standing should be reviewed each time a potential leave request is made when an employer's headcount is on the cusp; it can go in and out of eligibility. Smaller employers owned or managed by another must use the integrated employer test to determine if they collectively share enough common interest to be considered one employer for eligibility purposes.

Employee eligibility is dictated by three rules:

• Having worked a minimum of 12 calendar months over seven years, not necessarily consecutive. Accurate record-keeping is key for seasonal or re-hired employees.
• Having worked a minimum of 1,250 hours in the 12 months prior to requesting the leave – whether on a part- or full-time basis.
• A work location that employs 50 within a 75-mile radius. The rule shifts for remote workers to the location that assigns their work. The rule changes to the location that those without a fixed worksite report to. For remote managers, determinants are where they report to or where work is assigned from.

Beware of the complexities

There are a lot of pitfalls to be avoided to successfully comply with FMLA rules.

Many issues concern employee eligibility. Start with this: requirements, specifically the 50/75 rule, can't be waived, altered or ignored. Reading the fine print also helps. Take eligibility for temp-to-hire employees: their joint service time – hours worked and service months – counts toward eligibility when they are hired.

Another common mistake is failure to count leave as FMLA. This happens when FMLA isn't run concurrently with other leave policies, such as paid time off, sick leave or disability. It can result in lost work time and significant costs. This is compounded if employers don't track time qualified as FMLA leave, which occurs when HR isn't kept in the loop on an employee's reasons for the leave.

The intersection of FMLA with other regulated programs are a further complication. It may be necessary, for example, to explore reasonable accommodations after 12 weeks of FMLA unpaid are up for employees with conditions protected under the Americans with Disabilities Act (ADA). Said accommodation could well be an extension of unpaid leave, with the protections of the FMLA.

Related: FMLA: A 30-year celebration (and a call to Congress for paid family and medical leave)

The administrative challenges of the FMLA give plenty of cause for HR headaches. Long term, the cure can be a sound FMLA policy that outlines everything from notice requirements and medical certification rules to how it all aligns with company leave policies.

David Setzkorn is senior vice president and National Practice Leader for Absence Management at global Top 5 insurance brokerage Hub International out of Arizona.