Which condition should prevent a nail service?

Onychomycosis, a fungal infection of the nails, should prevent a nail service because it poses a risk of spreading the infection to other clients or the technician performing the service. Fungal infections can result in discoloration, thickening, and separation of the nail from the nail bed, and they often require medical treatment before any cosmetic nail services can be safely performed. Providing nail services on a client with onychomycosis not only compromises their health but can also lead to contamination of tools and equipment, potentially affecting the hygiene of the salon environment.

In contrast, conditions like nail polish, hangnail, and minor abrasions may not pose risks that would prevent a nail service. Nail polish is a cosmetic product that can simply be applied after performing necessary prep work. A hangnail can typically be managed with proper technique using sanitized tools. Minor abrasions may require extra care but are not definitively indicative of an infection or health concern that would necessitate cessation of service.