Nearly a century ago, the international community came to a clear consensus about the importance of people having a break or a day off from work during the week. In fact, shortly after its formation, the International Labour Organization (ILO) passed a convention to ensure that workers receive a full twenty-four hours of rest each week. Passed in 1921, the ILO's C14 Convention was created in response to profound concerns about the sweatshop hours that had emerged with industrialization. To date, 119 countries have ratified this treaty. This was not the only agreement that recognized the importance of time away from work. The Universal Declaration of Human Rights was adopted unanimously by the United Nations in 1948 and was reaffirmed by 171 countries in the Vienna Declaration of 1993. The importance of a day of rest is affirmed in article 24, which states that "everyone has a right to rest and leisure, including reasonable limitation of working hours and periodic holidays with pay."
Largely because of the disruption of circadian rhythms, working at night has negative health consequences for workers. Studies from a range of countries and industries have found that shift work is associated with sleep deprivation, fatigue, malaise, and an increased risk of physical and mental health disorders. Moreover, shift work is associated with higher divorce rates and poorer outcomes for children. Evening and night work can be costly for employees and their families not only in terms of their dependents' social, emotional and educational well-being, but also in terms of family economics. High-quality alternative care for dependent children or an elderly or disabled family member at night is scarce and often expensive. The ILO's Night Work Convention (Number 171) 1990 offers a number of approaches that can be taken at the governmental and firm level. These include mandating that workers deemed unfit for night work due to health reasons should, where feasible, be transferred to similar jobs that are done during the day time (Article 6). Alternatives to night work should also be made available to pregnant and nursing women as well as new mothers (Article 7) when night work, the disruption of circadian rhythms and stress are the least well tolerated.
In order to address the need for reasonable work hours and to minimize excessively long shifts, a significant number of countries have passed legislation to limit overtime. Other nations guarantee a wage premium for overtime work, meaning that wages for overtime hours are paid at a higher rate than regular hours. Some nations have adopted a dual-approach by both limiting mandatory overtime and offering premiums for overtime hours. At an international level, the UN's International Covenant on Economic, Social, and Cultural Rights (ICESCR) has declared that all countries should "recognize the right of everyone to the enjoyment of just and favorable conditions of work which ensure, in particular, reasonable limitation of working hours and periodic holidays with pay, as well as remuneration for public holidays." Only 157 countries have accepted the ICESCR.