When does a person with an occupational injury have a disability under the ''regarded as'' portion of the ADA definition?

When does a person with an occupational injury have a disability under the ''regarded as'' portion of the ADA definition? A person with an occupational injury has a disability under the ''regarded as'' portion of the ADA definition if s/he: (1) has an impairment that does not substantially limit a major life activity but is treated by an employer as if it were substantially limiting, (2) has an impairment that substantially limits a major life activity because of the attitude of others towards the impairment, or (3) has no impairment but is treated as having a substantially limiting impairment.