Whenever one works around anything that can make hair lengths fan (such as opening oven doors, any machine with a motor (whether
the motor itself is exposed or not such as lathes, drill presses, grinders, car engines, household fans), anything with heat (such as torches, welding
equipment, jeweler tools, lighting pilot lights, BBQs) or any recreational vehicle (such as go karts, and with unusually longer lengths, perhaps even bicycles), it is best to contain the hair in a reliable manner to prevent the hair being caught up in the equipment which could potentially result in major injury, including scalping. Hair should be drawn back in a reliable method to prevent falling or slipping such that any formerly contained hair could fall out in whole, or in part, and place one at risk. This may well mean that a ponytail for hair length is insufficient as hair fringe and bangs may remain vulnerable, and hair, during the course of a day can fall out.
Ponytailed hair means it’s only bound at one point yet the remaining length is loose hair which has a wide circumference it can still fall. Ponytailed hair can still fall forward if one is leaning over, or for example, in a kitchen with an open gas flame, can still fan out when one turns and the air flow from body movement can cause a pulse in the flame to a higher level and singe some hair. Same holds true with oven doors: ponytailed hair can fall forward on to hot surfaces when leaning over and get singed. Care around any flame should be taken including proximity to tools for lighting cigarettes and cigars. Often it is best to not only bind the hair; but also, position the hair inside a cap or bandanna such that the full head of hair is completely covered. This scenario is good not only around machinery but may well be a good idea in instances of working outdoors all day long, or when working in areas where fine dust and particulate matter is swirling about (paint, spraying, powder coating, laying tar) to prevent the hair being caked with such particles. Many industries have requirements for hair being contained to prevent worker injury. This likely includes those working in food services, construction, utilities, and machine shops of various sorts. Anytime one works in an area that can move the air flow, hair should be bound for safety of the person as hair is a very light weight substance and responds to the slightest of breezes. Of course, many professions do require containing the hair for reasons of public health, and a prime example is the food industry. Many sports may require similar constraints for reasons of safety to keep hair out of eyes and blocking one''s view, and to prevent being caught in sports equipment or trees and shrubs, or matted hair in severe weather conditions or water. This would include not allowing hair to fly loose on the backs of motorcycles and open-topped sports cars for longer tresses.