Use sunscreen with spf of 50. U can apply at home also. Windows and fluorescent bulbs can let through uv rays that can cause damage to your skin ? so unless you're in a windowless room with no light, your skin is receiving uv radiation.
Diploma In Trichology - Cosmetology, PG Diploma In Clinical Cosmetology (PGDCC), Diploma In Aesthetic Mesotherapy, PG Diploma In Clinical Research
Aesthetic Medicine Specialist, Ahmedabad
Actually, it depends on your skin type. In indian conditions spf 30 is more than enough. But at present senerio, spf 50 is compulsary. And cipla, rambaxy, Dr. Reddy, gsk. All these are leading brands in india providing very good sunscreen.