Both FMLA and ADA have been designed to grant leave, but characteristically they are very different from each other. While securing an FMLA leave is not difficult, it does not incorporate any provision for hardship. The provisions of ADA kick in when a serious health condition is recognized under FMLA that also has an element of disability. An employee may come under the purview of an ADA disability if his impairment limits one of his or her major life activities, which may affect his walking, talking, lifting, eating, thinking, breathing etc.



The Period of Leave
Under FMLA, an eligible employee is entitled to no more than 12 weeks of intermittent leave or leave for a block over a 12-month period. However, under ADA, it may extend beyond 12 weeks. The number of ADA leaves depends a lot on the prevailing circumstances and facts, can differ from one to another and even become more than 12 weeks.
ADA is the Last Resort
FMLA leave can go on concurrently with most types of leave such as vacation leave, disability leave, sick leave etc, but not ADA leave. The basic difference between ADA and any other leave is that to avail ADA, you need to exhaust all types of leaves you have. This is not the case with FMLA.
No Finite Leave Policy in ADA
There is no finite leave policy under ADA like in FMLA, where you are supposed to get 12 weeks of leave in a year for medical and similar emergencies. Under ADA, however, there is a finite element that is best defined by the employer himself. There is a maximum amount of leave that the employer can permit, for examples six months.
No Eligibility Criteria for ADA
To avail FMLA leave, you need to be eligible for it, and not everyone is eligible. Employees who have worked for at least a year and who have rendered at least 1,250 hours in a period of 12-months are only covered under FMLA regulations. However, every employee is covered under ADA, even if he or she has just joined the organization. ADA protects even the part-timers.
No Questions Asked
To grant FMLA leave, the employer can ask precise questions related to medical emergencies and the medical certification form. However, medical questioning under ADA is prohibited. There are some exclusions though, such as the questions asked to seek documents for ADA disability. Questions can also be asked by the employer to understand how to reasonably accommodate an employee.
Under ADA, the employer may also consider reassigning jobs to an employee who has developed some inability. So, if one has developed some kind of physical incapacity, the employer can look at all the vacancies in the organization at that material time and ask the individual whether he or she can perform any of the essential functions related to any of those jobs. So under ADA, the employee has the scope of finding a suitable position for him in the same organization, even if he develops an inability.
Conclusion
In essence, ADA is a comprehensive measure to accommodate incapacitated employees rather than work leave.