Best Padlocks for Lockout Tagout (LOTO): A Buyer's Guide for UK Industry
Best Padlocks for Lockout Tagout (LOTO): A Buyer's Guide for UK Industry
A standard padlock will not do for LOTO. This guide covers what to look for, which products from our range are suited to different applications, and answers the questions we get asked most often by safety managers and maintenance teams.
The Problem With Getting This Wrong
Lockout tagout procedures exist for one reason: to stop machinery from being re-energised while someone is working on it. In the UK, that obligation sits under the Provision and Use of Work Equipment Regulations 1998 (PUWER) and, for electrical isolation specifically, the Electricity at Work Regulations 1989. Get it wrong and you are not just looking at a fine — you are looking at a fatality.
The padlock is the last physical line of defence in that process. It is what prevents an isolation point from being re-energised, intentionally or otherwise. Yet many sites still use whatever happens to be in the stores: brass padlocks, combination locks, even cable ties. None of these are suitable.
A proper LOTO padlock does several things a standard padlock does not. It retains its key when open, so the lock cannot be removed from a hasp and left unsecured. It is non-conductive and non-sparking, which matters in electrical and flammable environments. It is colour-coded so ownership is immediately visible at the isolation point. And it is individually keyed — one lock, one key, one worker — so nobody else can remove it.
If your current LOTO programme uses anything other than purpose-built safety padlocks, fixing that is the starting point. Everything else in your procedure depends on it.
What to Look for in a LOTO Padlock
Non-conductive body
For any electrical isolation work, the padlock body must be plastic, nylon, or composite — not brass or steel. Metal bodies create conductivity risk. Non-conductive bodies also tend to be spark-resistant, which matters in environments where flammable gases or dust are present.
Key-retaining mechanism
When a LOTO padlock is open and placed onto a hasp, the key must stay in the lock. This prevents the padlock from being left dangling unlocked on an isolation point — a condition that defeats the entire purpose of the procedure. Most purpose-built safety padlocks have this as standard. If yours does not, replace them.
Individually keyed (keyed different)
Every worker involved in a LOTO procedure gets their own lock. Their key must not operate anyone else's. This is the "one person, one lock, one key" principle. It means a lock can only be removed by the person who applied it, which is what gives the procedure its integrity. Keyed-alike or master-key arrangements undermine this completely.
Colour coding
Colour is used across LOTO programmes to distinguish workers, trades, or isolation types. Red is the most common default. Some sites use a full colour matrix — electricians on yellow, mechanical on green, etc. Whatever your system, it only works if the padlocks come in consistent, clearly distinguishable colours. Faded or scratched locks cause confusion.
Shackle options
The standard shackle suits most applications, but two variants are worth knowing about. A long shackle (typically 70-82mm) gives additional clearance when stacking multiple padlocks on a group hasp or working with larger isolation devices. A wire/cable shackle is flexible and suited to confined spaces, irregularly shaped isolation points, or situations where a rigid shackle simply will not reach.
Engraving
Most safety padlocks accept engraving, either directly on the body or via a tag slot. Engraving the worker's name or ID number onto the lock makes ownership unambiguous during group isolation procedures and speeds up checks.
Our Recommended Products
ASEC Safety Lockout Tagout Padlock — Standard
The workhorse of most LOTO programmes. Non-conductive, non-sparking body, key-retaining function, available in six colours (red, yellow, blue, green, orange, black). The 40mm shackle suits the majority of standard hasps and valve lockout devices. If you are setting up a programme from scratch or standardising across a site, this is the sensible starting point.
Best for: General-purpose LOTO across electrical, mechanical, and hydraulic isolation points.
ASEC Safety Lockout Tagout Padlock — Standard
ASEC Safety Lockout Tagout Padlock — Long Shackle
The same non-conductive body and key-retaining mechanism as the standard version, but with an 82mm shackle height. The extra reach matters when you are stacking multiple padlocks on a group hasp, or working with circuit breaker lockouts and larger valve devices where a standard shackle does not clear the body of the lockout device.
Best for: Group isolation procedures, stacked hasps, and awkward isolation points with limited clearance.
ASEC Safety Lockout Tagout Padlock — Long Shackle
ASEC Safety Lockout Tagout Padlock — Wire Shackle
Where a rigid shackle is impractical, the 3mm flexible wire shackle version handles confined spaces and non-standard isolation points that would not accept a conventional padlock. The body retains the same non-conductive, non-sparking construction.
Best for: Confined spaces, cable entry points, and isolation devices with small or irregularly positioned locking holes.
ASEC Safety Lockout Tagout Padlock — Wire Shackle
ABUS 74/40 Safety Lock
Aluminium body construction, rated to withstand extreme temperatures and resistant to corrosive environments and hazardous chemicals. The ABUS 74/40 is built for the more demanding end of industrial LOTO — chemical plants, high-temperature environments, or any setting where the padlock will face conditions that would degrade a standard plastic body over time. Key-retaining function included.
Best for: Chemical, petrochemical, food processing, and high-temperature industrial environments.
ABUS 74/40 Safety Lock
ABUS T65AL/40
Lightweight vinyl-coated aluminium padlock with a hardened steel shackle and double-bolted locking mechanism. At 99g, it is noticeably lighter than most LOTO padlocks — relevant when workers are carrying multiple locks across a large site. The vinyl coating adds colour identification and protects the body in wet or corrosive conditions.
Best for: Sites where workers carry multiple padlocks, or where weight and portability matter.
ABUS T65AL/40 Coloured Aluminium Padlock
ASEC Electrical Lockout Tagout Kit
For sites that need to get a basic electrical isolation programme operational quickly, this kit contains the core components for standard electrical lockout procedures — padlock, hasp, tags, and the essential accessories — in a single package. Compact enough to store in a van or workshop.
Best for: Contractors, mobile maintenance teams, and smaller sites setting up electrical LOTO for the first time.
ASEC Electrical Lockout Tagout Kit
ASEC Advanced Electrical Lockout Tagout Kit
A comprehensive carry-case kit for complex electrical isolation. Includes a wider range of lockout devices, safety padlocks, tags, and accessories. Suited to facilities with multiple isolation point types — switchgear, MCBs, valves, and cable lockouts — where a single basic kit would fall short.
Best for: Facilities managers and maintenance teams responsible for multi-hazard isolation across a plant or building.
ASEC Advanced Electrical Lockout Tagout Kit
ASEC Mini Lockout Station
Lockout stations are how you keep a LOTO programme consistent. This compact wall-mounted unit holds up to 12 padlocks (sold separately), keeps equipment visible and accessible, and reduces the time workers spend locating their lock before starting an isolation. Placing stations close to the point of use is one of the simplest ways to improve programme compliance.
Best for: Any site running a formal LOTO programme. Position near plant rooms, switchgear rooms, or maintenance access points.
ASEC Mini Lockout Tagout Station
Multi-Unit Orders
If you are equipping a team, standardising across a site, or setting up a new LOTO programme, we can advise on quantities, colour allocation, and keying arrangements. Use the "Spec My Project" option or contact us directly.
FAQ
What is the difference between lockout and tagout? Lockout means physically securing an energy isolation point with a padlock so it cannot be re-energised. Tagout means attaching a warning tag to indicate that equipment must not be operated without a physical lock. UK guidance from the HSE generally favours lockout over tagout wherever practical, because a tag alone can be removed or ignored. Tagout is typically used only where the design of the isolation point makes lockout impossible.
Are LOTO padlocks a legal requirement in the UK? PUWER 1998 requires that work equipment can be isolated from energy sources and that isolation is maintained safely. The Electricity at Work Regulations 1989 impose a similar duty for electrical systems. Neither regulation specifies padlocks by name, but using purpose-built LOTO padlocks is the accepted means of demonstrating compliance. An HSE inspector finding standard padlocks or combination locks in use would treat that as a deficiency.
Can I use a combination lock for LOTO? No. Combination locks allow the code to be known by multiple people simultaneously, which means anyone who knows the combination can remove the lock — including someone unaware that maintenance is in progress. The "one person, one key" principle cannot be enforced with a combination lock.
Do all workers need their own padlock? Yes. Each person involved in an isolation procedure must apply their own lock. If three workers are on a job, three locks go on the hasp. No single person can remove the lock applied by another. This is the core of the procedure's safety logic.
What colours should we use? There is no UK-mandated colour standard for LOTO padlocks. Red is the most widely used default. Many sites adopt a colour-per-trade system. Whatever you choose, document it in your written LOTO procedure and apply it consistently. Inconsistency is where colour coding stops working.
Can LOTO padlocks be used in flammable environments? Non-conductive plastic and composite body padlocks are spark-resistant and suitable for most flammable environments. If you are working in a Zone 1 or Zone 2 ATEX-classified area, check the specific padlock specification against the area classification requirements. The ABUS 74/40 and ASEC non-conductive range are the relevant products here.
How do I manage group lockout procedures? Group lockout uses a hasp — a device that accepts multiple padlocks simultaneously. Each worker in the group applies their own lock. The isolation point cannot be re-energised until every lock has been removed, meaning every worker has finished and cleared the area. We stock non-conductive hasps for electrical applications alongside our LOTO padlock range.
Should LOTO padlocks be engraved? Engraving is not mandatory but strongly recommended. An engraved name or ID number removes any ambiguity about who applied a lock, which matters if a worker leaves a site mid-job or there is a dispute about whether an isolation is still active. Most of our LOTO padlocks accept engraving — contact us if you need this for a bulk order.
All products referenced in this guide are available in our Safety Padlocks collection. For multi-unit orders or site-specific advice, use the Spec My Project option or call us directly.