Which Safety/Lockout Padlock Suits Your Requirements?

Safety padlocks are designed to lock equipment, valves, or electrical junctions to prevent accidental operation during maintenance or repair work. They can also be used to restrict access to specific areas while work is being carried out. Preventing unexpected re-energisation of machinery is a core part of industrial safety, especially in environments where multiple people are working simultaneously.

Why Colour-Coding Matters

Coloured safety padlocks help identify who is working on a machine at a glance. A colour can represent:

A trade or role (e.g., electricians, mechanical engineers)
A team or contractor
A specific location or work area

This visual clarity reduces confusion and helps ensure that equipment is not reactivated while someone is still working on it.

Keying Systems: Choosing the Right One

Selecting the appropriate key system is essential for safe lockout/tagout procedures.

Key Differ (KD)

Each padlock has its own unique key.
Ideal where multiple personnel are working in the same area.
Prevents one worker from opening another person’s lock.
Supports safe, independent isolation.

Keyed Alike (KA)

One key opens all padlocks within the same keyed-alike group.
Suitable when a single employee needs to control multiple locks.
Each worker still has their own colour/key group.
Ensures efficient operation without compromising safety.

Master Key (MK) Option

Used in more complex lockout systems.
Individual locks operate under KA or KD, but a single master key can open all locks.
The master key must be kept in a secure place and used only in emergencies by authorised management.

Using Lockout Hasps for Multiple Workers

When several individuals are working on the same equipment, a lockout hasp allows multiple padlocks to be attached to a single isolation point. This ensures the equipment cannot be re-energised until every worker has removed their padlock, confirming work is complete.

Example Recommendation: Zenex S31 Safety Padlock (40mm)

The Zenex S31 is widely used in lockout/tagout environments.

Key features include:

Supplied with “Danger – Locked Out – Do Not Remove” warning label as standard.
Additional writable labels included for personal identification.
Available in six colours for clear visual coding.
Choice of keyed alike or key differ.
Constructed from Xenex alloy, resistant to chemicals, UV and impact.
Temperature resistance from -70°F to +350°F.
Key-retaining design (key cannot be removed unless locked) for safe use.
Key differ versions offer over 100,000 configurations, making accidental cross-keying extremely unlikely.