What is an occupational disease?
Article 157 of the General Social Security Law links occupational disease to three elements: the work performed, an activity included in the regulatory table, and exposure to the agent or substance specified for that disease. Royal Decree 1299/2006 contains this table and regulates notification and registration criteria. For self-employed workers covered for occupational contingencies, the relationship with the activities and agents listed in the table also applies.
This is a legal definition for recognizing a contingency. From a prevention perspective, the analysis is broader: a health condition may be caused or aggravated by work, even if its administrative classification requires other evidence or is legally framed differently.
Differences with work accident and work-related illness
Workplace accidents are usually associated with an event or injury connected to work, while many illnesses develop after repeated exposures and may manifest after a latency period. However, the boundary does not depend solely on whether the damage is sudden or slow. The General Social Security Law allows certain illnesses not included in the list of covered illnesses to be considered workplace accidents when it is proven that work was their sole cause.
“Work-related illness” is a broader preventive expression: it includes injuries in which working conditions contribute to, aggravate or accelerate the process, even if they do not meet the closed requirements of article 157. It should not be used as an automatic synonym for the legal contingency “occupational disease”.
How is it classified in Spain?
Annex 1 of Royal Decree 1299/2006 organizes the table into six groups according to the agent: chemical , physical , biological , diseases caused by inhalation of substances and agents , skin diseases , and diseases caused by carcinogenic agents . Each entry links the disease, the agent, and the main activities capable of producing it.
Annex 2 contains a supplementary list of diseases suspected of being occupational and whose possible future inclusion should be considered. This list alone does not constitute the same classification as the table in Annex 1. Updating the table is the responsibility of the Government through the established procedure; therefore, a company’s information sheet cannot replace an examination of the current regulations or an assessment of the specific case.
How it is detected, reported, and investigated
Detection can be based on symptoms, health surveillance , healthcare, environmental findings, or case clusters. The managing or collaborating entity responsible for occupational risk coverage prepares and processes the report in accordance with Order TAS/1/2007; the company must provide the corresponding information. The electronic communication system is known as CEPROSS.
The notification does not close the preventive investigation. Tasks and exposures, products, equipment, times, process changes, collective and individual protection measures, and work history in other positions must be reconstructed. Other potentially exposed individuals are also identified. The INSST proposes a multidimensional approach to the causes, which is useful for avoiding simplistic explanations focused solely on individual behavior or the last position held.
How to prevent it
Prevention begins before harm occurs: identifying agents and conditions, assessing exposure, and applying the prevention hierarchy. First, the risk is avoided; then, the agent or process is replaced, action is taken at the source through containment, extraction, or safe automation, and organizational measures are implemented. Personal protective equipment is an additional barrier when residual risk requires it.
Information and training must be tailored to actual exposure. Health surveillance is focused on job-specific risks, respects confidentiality and privacy, and can help detect early effects. Collective results, without identifying individuals, are used to review the assessment. The company maintains the required documentation and reviews measures when harm occurs or there are indications of insufficient prevention.
Practical example
In a workshop with presses, an individual presents with hearing loss consistent with continuous noise exposure. The investigation goes beyond simply verifying whether they used hearing protection. It reviews historical measurements, exposure times, maintenance, enclosures, shift scheduling, protection selection and fitting, training, and audiometric monitoring. It also analyzes other individuals who have worked in similar conditions.
If the disease, the agent, and the activity described in the table are present, it can be processed as an occupational disease. Regardless of the administrative outcome, the occurrence of the case requires a review of the assessment and prioritization of controls at the source: reducing machine noise, insulation, maintenance, and limiting exposure. Follow-up verifies that the measures effectively reduce exposure.
Regulatory framework in Spain
Law 31/1995 defines work-related injuries and mandates the protection, assessment, planning, reporting, and monitoring of health based on risks. Royal Legislative Decree 8/2015 establishes the concept of occupational disease for Social Security purposes. Royal Decree 1299/2006 approves the table, its updates, and the notification and registration criteria; Order TAS/1/2007 implements the electronic reporting system.
Specific exposure standards—for example, those relating to chemical, biological, or carcinogenic agents, noise, or asbestos —define preventive measures and, in some cases, health monitoring. The assessment of a case falls to the competent authorities; the company and its prevention organization must provide reliable data and address the underlying causes without waiting for the harm to recur.
