The employer must genuinely believe that the qualification is essential to the job. The decision must be based on objective evidence, and the employer has explored reasonable accommodations.If a company requires airline pilots to have perfect vision, it must honestly and in good faith demonstrate that this requirement is reasonably necessary for safety—not just a preference or assumption.

This principle ensures that BFOQs are used narrowly and responsibly, protecting both business needs and employee rights.

Indirect descrimination - Height and weight may relate to disability or specific ethnic groups. Using postal codes may amount to systemic discrimination as it may relate to race, ancestry, or place of origin. Tribunals will consider impact, not just intent. Even if a category isn't listed, if the effect of a policy or decision result in unfair treatment of a protected group, it can still be challenged. Increasingly courts recognize intersectionality and implicit bias.