Detection and monitoring in the workplace of alcohol and drug consumption

2026-01-26T18:26:00
Portugal

Key points of ACT Technical Note 14

Detection and monitoring in the workplace of alcohol and drug consumption
January 26, 2026

The Authority for Working Conditions (“ACT”) has recently published Technical Note 14, which addresses the detection and monitoring in the workplace of excessive alcohol and psychoactive substance consumption. Specifically, this note clarifies the legal framework, limitation and best practices applicable to employers.

Below is a summary of the key points of this note, analyzed from labor and data protection perspectives.

Framework

Psychoactive substance consumption may endanger employee health and safety, as well as that of others. For this treason, addressing this issue is essential as part of a comprehensive occupational health and safety (“OHS”) risk prevention strategy.

Employers are obligated to organize OHS services and provide continuous health and safety conditions. In contrast, employees must comply with health and safety standards, cooperate to improve OHS, and attend scheduled appointments and tests prescribed by occupational health physicians.

Monitoring procedures for psychoactive substances must be integrated into the OHS process. The ACT emphasizes that these procedures should only be performed by health professionals, primarily occupational health physicians, who are bound by confidentiality obligations.

Regulating the prevention and monitoring of psychoactive substance consumption

Employers may regulate the prevention and monitoring of alcohol and other substance consumption through internal regulations; however, these regulations must not impose excessive or generalized restrictions.

Internal regulations must clearly and proportionately define: the target substances, their limits and scientific rationale; the circumstances under which testing will occur; the professionals involved in implementing these measures; the purpose and frequency of testing; employees’ opportunities for counter-testing; notification of test results to the employee; procedures for handling positive results; and confidentiality mechanisms.

Employers must consult the employee committee before adopting such regulations. If no such committee exists, employers must instead consult inter-union committees, trade union committees or trade union representatives. Regulations will only take effect once they have been communicated to the employees.

Limits to monitoring in the workplace

Monitoring psychoactive substance consumption in the workplace must respect employees’ fundamental rights, including moral and physical integrity, privacy and personal data protection. Also, the monitoring must align with the company’s OHS and HR policies.

The ACT advises that screenings, when part of a prevention and monitoring program, must serve as a last resort and must comply with applicable legal and contractual obligations.

Processing personal data

Tests and assessments to monitor psychoactive substance consumption are permissible within the scope of preventive and occupational health. Specifically, they may be carried out to assess professional fitness, diagnose or provide health care, meet legal OHS obligations, or prevent risks to employees or others.

Conducting medical tests and medical examinations for the detection of psychoactive substance use involves processing employees’ personal data, including their health data. For this reason, conducting such tests and assessments is subject to the General Data Protection Regulation (“GDPR”) and the GDPR Implementation Law.

When processing health data, employers must adhere to the principles of minimization, necessity, proportionality, confidentiality, lawfulness, fairness, transparency, and storage limitation.

From minimization and proportionality standpoints, the ACT states that monitoring the consumption of psychoactive substances is not permissible when the associated risks are minimal.

Also, maintaining widespread, detailed records of consumption (potentially enabling the creation of employee profiles) is considered excessive and potentially discriminatory.

For specific job categories, surveillance measures and the recording of diagnostic support tools or tests may be adopted to prevent harm to the physical integrity of employees or others. This is particularly pertinent for professionals who perform high-risk duties, such as energy technicians or heavy and light goods transport drivers.

Lawful procedures to monitor psychoactive substance consumption are limited to those conducted for preventive or curative health purposes. Also, these procedures must follow the applicable rules and involve the processing of personal data by a health professional bound by a duty of confidentiality. These procedures must be justified or carried out at the explicit request of the employee.

Handling test results

The ACT clarifies that the detection of a blood alcohol level cannot, in isolation, determine an employee’s fitness for work. Occupational health physicians must arrive at such decisions based on direct observation of the employee and clinical criteria.

Employers may only receive essential information pertaining to fitness/non-fitness, not detailed test results.

Also, an employee’s refusal to undergo tests cannot be equated with a positive result and must be assessed under the applicable disciplinary regime.

The ACT also notes that, in cases of non-fitness, occupational health physicians may propose alternative duties that the employee can perform.

Behavior-based assessment

The ACT emphasizes that “it is the breach of the employee’s work duties, and not mere non-fitness resulting from a test, that can justify a disciplinary procedure and any application of a disciplinary sanction.”

Consuming psychoactive substances outside working hours and the workplace, provided it is unrelated to work, does not constitute a disciplinary infraction.

Practical recommendations for employers

  • Develop a prevention and monitoring program integrated into OHS, focused on raising awareness among employees.
  • Establish clear and proportionate internal regulations governing substance monitoring.
  • Conduct testing only when justified.
  • Define procedures for temporary removal due to non-fitness, reassignment to compatible roles, and behavioral assessments in disciplinary procedures.
  • Collaborate closely with the occupational health department in structuring and executing prevention and monitoring programs.
  • Enter subcontracting agreements with OHS service providers.         
  • Data protection best practices:
      • Prioritize data minimization, proportionality and limited storage durations. Do not develop detailed substance consumption profiles for employees.
      • Provide employees with transparent information, supported by suitable legal grounds.
      • Implement security measures to ensure the confidentiality and integrity of personal data, guaranteeing secrecy.
      • Perform data protection impact assessments to manage risks associated with processing employees’ special category data.
      • Restrict access to health data; specifically, only health professionals bound by confidentiality duties may process special category data, while HR teams must be limited to receiving medical fitness results.
January 26, 2026