Lights used indoors are meant to be used indoors. When using below the standards, the lights get hot and can overheat. If the lights are being used outdoors, a lighting fixture should be used. This is because the light fixture creates a better heat shield between the bulb and the fixture. If the bulbs were kept in their original packaging and stored in a cool, dry place, then the bulbs should be fine for outdoor use. Some fixtures will let you know if it is an outdoor fixtures. The fixture is not meant to be a permanent fixture. It might blow out if exposed to too much snow, rain, etc.