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Title I of the Americans with Disabilities Act of 1990 (the "ADA")(1)requires an employer(2)to provide reasonable accommodation to qualified individuals with disabilities who are employees or applicants for employment, unless to do so would cause undue hardship. "In general,an accommodation is any change in the work environment or in the way things are customarily done that enables an individual with a disability to enjoy equal employment opportunities." There are three categories of "reasonable accommodations":
"(i) modifications or adjustments to a job application process that enable a qualified applicant with a disability to be considered for the position such qualified applicant desires; or
(ii) modifications or adjustments to the work environment, or to the manner or circumstances under which the position held or desired is customarily performed, that enable a qualified individual with a disability to perform the essential functions of that position; or
(iii) modifications or adjustments that enable a covered entity's employee with a disability to enjoy equal benefits and privileges of employment as are enjoyed by its other similarly situated employees without disabilities."
The duty to provide reasonable accommodation is a fundamental statutory requirement because of the nature of discrimination faced by individuals with disabilities. Although many individuals with disabilities can apply for and perform jobs without any reasonable accommodations, there are workplace barriers that keep others from performing jobs which they could do with some form of accommodation. These barriers may be physical obstacles (such as inaccessible facilities or equipment), or they may be procedures or rules(such as rules concerning when work is performed, when breaks are taken, or how essential or marginal functions are performed). Reasonable accommodation removes workplace barriers for individuals with disabilities. When an individual decides to request accommodation, the individual or his/her representative must let the employer know that s/he needs an adjustment or change at work for a reason related to a medical condition. To request accommodation, an individual may use "plain English" and need not mention the ADA or use the phrase "reasonable accommodation." So yes, you have a medical disability and a reasonable accommodation does not put an undue hardship on your employer (providing a simple heater). It seems that your employer has possibly discriminated against you by not allowing you a heater and you could have a claim under the ADA with the EEOC.
As for the times you were written up, you would need to prove that you were being discriminated against as part of a protected class (this could be a person with a disability), you would also need to show that these writ ups were not valid which can be VERY difficult. You should probably stick to the ADA claim but if the discrimination continues you should know that a claim for discrimination might be possible. Document everything from now on for evidence.
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