321J.11  Taking sample for test.
  Only a licensed physician, licensed physician assistant as defined in section 148C.1, medical technologist, or registered nurse, acting at the request of a peace officer, may withdraw a specimen of blood for the purpose of determining the alcohol concentration or the presence of a controlled substance or other drugs. However, any peace officer, using devices and methods approved by the commissioner of public safety, may take a specimen of a person’s breath or urine for the purpose of determining the alcohol concentration, or may take a specimen of a person’s urine for the purpose of determining the presence of a controlled substance or other drugs. Only new equipment kept under strictly sanitary and sterile conditions shall be used for drawing blood.
  The person may have an independent chemical test or tests administered at the person’s own expense in addition to any administered at the direction of a peace officer. The failure or inability of the person to obtain an independent chemical test or tests does not preclude the admission of evidence of the results of the test or tests administered at the direction of the peace officer. Upon the request of the person who is tested, the results of the test or tests administered at the direction of the peace officer shall be made available to the person.
86 Acts, ch 1220, §11; 88 Acts, ch 1225, §26; 98 Acts, ch 1138, §19