7. On a company's job application form, there is a column requesting personal data concerning the applicant's spouse/children's occupations. The purpose of this is to ascertain whether the relatives work for one of its competitors. Is this acceptable?

The test is whether the data collected are necessary to fulfill the employer's purpose of ascertaining whether relatives of the job applicant work for a competitor. To find this out, it is only necessary to ask whether or not the applicant's relatives work in the same or a similar field. If they do, further questions could be asked to ascertain whether this should be a source of concern. But if they do not, the employer does not need to know what their actual occupations are, and hence the employer should not collect this information.