(dating) A prescheduled phone call to another person who knows where one is and who one was going out with. A missed check-in (or using a pre-arranged code phrase for danger) signals one's contact person to call for help.

(Australia, informal, humorous) Inappropriate or unsafe footwear in an industrial workplace.

plural of safety factor

plural of safety catch

A cage for an elevator or mine lift, having appliances to prevent it from dropping in the event that the lifting rope breaks.

(chemistry) A tube to prevent explosion, or to control delivery of gases by an automatic valvular connection with the outer air; especially, a bent funnel tube with bulbs for adding those reagents which produce unpleasant fumes or violent effervescence.

A reflector intended for pedestrians, runners, and motorized and non-motorized vehicles. It aids visibility of a person or vehicle as it reflects light from headlights of vehicles.

plural of safety bicycle

(dated) A style of bicycle that superseded the penny-farthing or ordinary and is now the most common type of bicycle.

plural of safety chain