The conditions under which employees have to work. This includes matters such as permitted breaks, the state of heating, lighting, and ventilation of workplaces, the safety and comfort of machinery, vehicles, and other equipment, normal manning levels, and disciplinary procedures. These conditions are affected by legislation, for example under the Health and Safety at Work Act, by collective bargaining between employers and trade unions representing workers, and by voluntary improvements by employers who believe that better working conditions pay for themselves in terms of staff morale and loyalty, as well as productivity.