Electric energy is an invisible and fatal hazard. Unlike a moving machine or working at height, electricity emits no sound and cannot be seen before contact. Due to this unpredictability, any intervention in electrical installations requires an extreme level of control and planning. 

The basis of this control lies in the NR10 electrical safety standard, which requires documentation, rigorous planning, and a formal release for workers to perform tasks on the electrical grid. 

In this article, we will detail how the authorization for electrical work works, when a Work Permit (PT) is indispensable, how NR-10 guidelines connect with the rest of your company's safety ecosystem, and what changes with the new revision of the standard. 

NR10 Electrical Safety: The pillar of prevention 

Regulatory Standard 10 (NR-10) establishes the minimum requirements and conditions to guarantee the health and safety of workers who interact directly or indirectly with electrical installations and services involving electricity. 

Its basic premise is de-energization. The general rule of the standard is that electrical interventions can only occur with the system completely de-energized (and locked out). Working on energized circuits is the exception and requires technical justifications, special protocols, and double protection barriers.

NR10 work authorization: Who can intervene in the grid? 

In the industrial environment, simply having training in the electrical field is not enough to perform interventions. NR-10 establishes that technical knowledge is only the first step, not the guarantee of authorization to work. 

To work on the grid, professionals must have the nr10 work authorization, which is a formal document granted by the company. See the classification of profiles required by the standard: 

Only authorized workers can perform electrical interventions, and the authorization status must always be explicitly displayed on the employee's badge. 

The role of the Work Permit (PT) in electrical services 

Even if a worker is qualified, registered, and authorized by the company, they cannot simply open a panel and start maintenance. This is where operational lockout comes in: the Work Permit. 

The issuance of the PT is mandatory, according to NR-10, for services performed in High Voltage (HV) or on energized electrical installations. The document acts as an immediate checklist at the job site, certifying that the appropriate personal protective equipment (PPE) is being used and that the area has been properly signed and isolated. 

If your operation needs to structure this flow, understanding in detail what a Work Permit is will help define the responsibilities of whoever issues, verifies, and executes the task. 

The Planning: The Preliminary Hazard Analysis (PHA) 

Before the Work Permit is signed on the factory floor, the task had to be planned. No complex electrical activity proceeds without a Preliminary Hazard Analysis (PHA). 

The PHA is the technical study where the safety engineer or technician details the steps of the maintenance, predicts failures (such as electric arc, shock, or short circuit), and defines the necessary barriers (flame-resistant clothing, insulating gloves, and appropriate tools). Since it is the foundation of all safe planning, knowing exactly what a preliminary hazard analysis (PHA) is and how to structure this document prevents unwanted surprises and accidents at the time of execution. 

What changes with the New NR-10 (2026 Update)? 

To reinforce accident prevention and demand even more rigorous planning from companies, the Ministry of Labor and Employment published the fifth revision of NR-10 (MTE Ordinance No. 737, of May 29, 2026). 

The new wording focuses on modernizing requirements and harmonizing with the current Occupational Health and Safety regulatory structure (such as the PGR), improving the way electrical risks are managed. 

Important deadlines and adjustments: 

• The new NR-10 will enter into force on June 1, 2027 (one year after its publication). 

  
  

• There will be specific and distinct deadlines for adjusting existing electrical installations. 

  
  

• An official tripartite body was created to monitor the implementation and evaluate the practical effects of these changes in work environments. 

Simultaneous Risks: NR-10 and other critical activities 

In industries, risks rarely exist in isolation. It is common for the authorization for electrical work to need to be combined with other high-risk work permits. 

If your electrical team needs to intervene in complex environments, the documentation and precautions multiply. See the main intersections of NR-10 with other standards: 

• Maintenance on poles or towers: When the intervention occurs above two meters, the rules and equipment for work at height (NR-35) must be applied simultaneously with NR-10. 

  
  

• Use of grinders or welding near electrical grids: The presence of sparks near wiring adds a fire hazard, requiring specific protections and authorization for hot work (NR-34). 

  
  

• Repairs in underground galleries or confined panels: Interventions in locations with restricted ventilation demand, in addition to electrical lockout, the rigorous atmospheric measurements required for confined spaces (NR-33). 

  
  

Ensuring full compliance with NR-10 is not just a matter of avoiding fines, but of saving lives. Structure clear processes, ensure that only authorized personnel touch installations, prepare for the new updates to the standard, and never skip documentation rigor when issuing PHAs and Work Permits.