The ADA does not override health and safety requirements established under other Federal laws even if a standard adversely affects the employment of an individual with a disability. If a standard is required by another Federal law, an employer must comply with it and does not have to show that the standard is job related and consistent with business necessity. For example, employers must conform to health and safety requirements of the U.S. Occupational Safety and Health Administration. However, an employer still has the obligation under the ADA to consider whether there is a reasonable accommodation, consistent with the standards of other Federal laws, that will prevent exclusion of individuals with disabilities who can perform jobs without violating the standards of those laws. If an employer can comply with both the ADA and another Federal law, then the employer must do so.

The ADA does not override State or local laws designed to protect public health and safety, except where such laws conflict with the ADA requirements. If there is a State or local law that would exclude an individual with a disability from a particular job or profession because of a health or safety risk, the employer still must assess whether a particular individual would pose a "direct threat" to health or safety under the ADA standard. If such a "direct threat" exists, the employer must consider whether it could be eliminated or reduced below the level of a "direct threat" by reasonable accommodation. An employer cannot rely on a State or local law that conflicts with ADA requirements as a defense to a charge of discrimination.

Yes. The ADA permits employers to establish qualification standards that will exclude individuals who pose a direct threat -- i.e., a significant risk of substantial harm -- to the health or safety of the individual or of others, if that risk cannot be eliminated or reduced below the level of a "direct threat" by reasonable accommodation. However, an employer may not simply assume that a threat exists; the employer must establish through objective, medically supportable methods that there is significant risk that substantial harm could occur in the workplace. By requiring employers to make individualized judgments based on reliable medical or other objective evidence rather than on generalizations, ignorance, fear, patronizing attitudes, or stereotypes, the ADA recognizes the need to balance the interests of people with disabilities against the legitimate interests of employers in maintaining a safe workplace.

An employer may not ask or require a job applicant to take a medical examination before making a job offer. It cannot make any pre-offer inquiry about a disability or the nature or severity of a disability. An employer may, however, ask questions about the ability to perform specific job functions and may, with certain limitations, ask an individual with a disability to describe or demonstrate how s/he would perform these functions.

An employer may condition a job offer on the satisfactory result of a post-offer medical examination or medical inquiry if this is required of all entering employees in the same job category. A post-offer examination or inquiry does not have to be job-related and consistent with business necessity.

However, if an individual is not hired because a post-offer medical examination or inquiry reveals a disability, the reason(s) for not hiring must be job-related and consistent with business necessity. The employer also must show that no reasonable accommodation was available that would enable the individual to perform the essential job functions, or that accommodation would impose an undue hardship. A post-offer medical examination may disqualify an individual if the employer can demonstrate that the individual would pose a "direct threat" in the workplace (i.e., a significant risk of substantial harm to the health or safety of the individual or others) that cannot be eliminated or reduced below the "direct threat" level through reasonable accommodation. Such a disqualification is job-related and consistent with business necessity. A post-offer medical examination may not disqualify an individual with a disability who is currently able to perform essential job functions because of speculation that the disability may cause a risk of future injury.

After a person starts work, a medical examination or inquiry of an employee must be job-related and consistent with business necessity. Employers may conduct employee medical examinations where there is evidence of a job performance or safety problem that they reasonably believe is caused by a medical condition, examinations required by other federal laws, return-to-work examinations when they reasonably believe that an employee will be unable to do his job or may pose a direct threat because of a medical condition, and voluntary examinations that are part of employee health programs.

Information from all medical examinations and inquiries must be kept apart from general personnel files as a separate, confidential medical record, available only under limited conditions.

Tests for illegal use of drugs are not medical examinations under the ADA and are not subject to the restrictions of such examinations.