Short answer. Eight hours a day. Article 83 of the Labor Code provides that the normal hours of work of any employee shall not exceed eight hours a day. A special rule covers health personnel: eight hours a day for five days a week, with at least thirty percent additional pay when the exigencies of the service require a sixth day.
What the law says
The normal hours of work of any employee shall not exceed eight (8) hours a day.
Labor Code, Article 83 — Normal Hours of Work. Read the full provision →
A ceiling, not a quota
The article's first sentence is the general rule: The normal hours of work of any employee shall not exceed eight (8) hours a day. Read the verb carefully — shall not exceed. Eight hours is the maximum that counts as a normal day's work, not a number every workday must reach; an employer is free to set a shorter workday. What the ceiling controls is the boundary between normal work and work beyond it: hours past the eighth are no longer part of the normal day, which is why they are dealt with, and compensated, separately under the Code.
The special rule for health personnel
The article carves out hospital and clinic workers in larger settings — cities and municipalities with a population of at least one million (1,000,000) or hospitals and clinics with a bed capacity of at least one hundred (100). These personnel shall hold regular office hours for eight (8) hours a day, for five (5) days a week, exclusive of time for meals. The Code then prices the exception to its own rule: where the exigencies of the service require six days or forty-eight hours of work, the employee is entitled to an additional compensation of at least thirty percent (30%) of their regular wage for work on the sixth day.
Who counts as health personnel
The article defines its own coverage, and the list is long: resident physicians, nurses, nutritionists, dietitians, pharmacists, social workers, laboratory technicians, paramedical technicians, psychologists, midwives, attendants and all other hospital or clinic personnel. The closing phrase matters most — all other hospital or clinic personnel sweeps in workers beyond the named professions, so the five-day rule and the thirty-percent premium are not limited to medical staff in the strict sense. Whether the workplace itself meets the population or bed-capacity thresholds is the first question; who the worker is comes second.
Reading your own workday against the article
Start with your actual schedule: count the hours you are required to be at work, and note that for health personnel the article computes the day exclusive of time for meals. If your required hours regularly exceed eight, the excess is not simply absorbed into the normal day. One caution on citations: the Labor Code's articles have been administratively renumbered, so the same provision is sometimes cited under a different number in other sources — the substance of the rule is what matters. An employee who suspects a violation should bring payslips and the written work schedule to a consultation, since those two documents usually decide the question.