Safe Systems of Work (SSoW) & Digital Permits

Under the Electricity at Work Regulations 1989 (EAWR), it is an absolute legal requirement that precautions must be taken to prevent danger when working on or near electrical equipment. The fundamental mechanism for controlling high-risk electrical tasks is the implementation of a formal Safe System of Work (SSoW).

This TMUK Group digital tool allows Qualified Supervisors and Authorised Persons to instantly generate, document, and print formal isolation tracking documentation directly from the field, ensuring compliance and clear communication of responsibilities.

Types of Electrical Safety Documentation

• Electrical Permit to Work (PTW): The primary document issued to a Competent Person. It explicitly confirms that the specified apparatus has been made dead, isolated, securely locked off, and proven dead. It authorises physical work to commence on the conductors.
• Sanction for Test: Because testing often requires the temporary removal of earths or the application of diagnostic voltages, a standard PTW cannot be used. A Sanction for Test specifically outlines the hazards and control measures required when verifying circuit parameters under Guidance Note 3.
• Limitation of Access: Used to control the entry of non-electrical personnel (e.g., cleaners, painters, mechanical fitters) into areas where live electrical hazards exist (such as substations or switch rooms). It defines the strict physical boundaries they must not cross.

The Golden Rules of Safe Isolation

A Permit to Work is only valid if the physical isolation procedure has been executed flawlessly. The issuer must ensure that the source of supply is identified, the switchgear is locked in the OFF position, the key is retained by the person doing the work, and the circuit is proven dead using a GS38-compliant voltage indicator (tested before and after on a proving unit).