I read the article by Townsend et al (May 2004)1 with great interest as well as consternation. Although the authors would have the reader believe that the errors referred to are due to equipment error, based on the examples given, whether or not there is a hardware problem (eg, flow-sensor “zero error”) or a software problem (eg, the inability to delete inaccurate volume-time or flow-volume curves), the individual who is administering the spirometry test and/or the individual interpreting the results should be able to recognize that a problem exists. I submit that the individuals administering the spirometry tests were ill-trained; otherwise, these errors would not have escaped their scrutiny. I was especially disturbed by the data presented on respiratory screening programs for respirator clearance. Why was this not picked up? Again, I submit, human error. The authors point out that the results of the aforementioned tests were useless and “… could be harmful to the employee….” I would ask, if any of the aforementioned cases went to litigation, who would be the defendant, the “spirometer” or the technician and interpreter?