Safety locks

Safety locks

Maintenance and safety engineers in manufacturing, utilities, and construction require padlocks that do more than secure assets — they must enforce Lockout/Tagout (LOTO) procedures and protect personnel from hazardous energy release. Master Lock industrial padlocks and safety locks are engineered for these demands, covering both physical security and regulatory compliance across harsh operating environments.

Safety locks
Body Height (mm)
Body Width (mm)
Colour
Product type
Manufacturer
Weikght (kg)
Shackle Height (mm)
Shackle Diameter (mm)
S2394
Code: S2394
On site: 5+ gab On site: 0 gab

Supplier:

16.89 EUR
15.20 EUR (w/o VAT)
XCSZ200
Code: XCSZ200
On site: 5+ gab On site: 0 gab

Supplier:

21.90 EUR (w/o VAT)
420
Code: 420
On site: 5+ pcs On site: 0 pcs

Supplier:

7.94 EUR (w/o VAT)
428
Code: 428
On site: 4 pcs On site: 0 pcs

Supplier:

7.39 EUR (w/o VAT)
S2392
Code: S2392
On site: 4 pcs On site: 0 pcs

Supplier:

9.24 EUR (w/o VAT)
S2391
Code: S2391
On site: 3 pcs On site: 0 pcs

Supplier:

9.24 EUR (w/o VAT)
421
Code: 421
On site: 3 pcs On site: 0 pcs

Supplier:

9.65 EUR (w/o VAT)
S3477
Code: S3477
On site: 1 pcs On site: 0 pcs

Supplier:

45.58 EUR (w/o VAT)
S3476
Code: S3476
On site: 1 pcs On site: 0 pcs

Supplier:

23.56 EUR (w/o VAT)
103003508
Code: 103003508
On site: 1 pcs On site: 0 pcs

Supplier:

104.75 EUR
78.56 EUR (w/o VAT)
483
Code: 483
On site: 1 pcs On site: 0 pcs

Supplier:

54.96 EUR (w/o VAT)
LMPBLSQ55
Code: LMPBLSQ55
On site: 1 pcs On site: 0 pcs

Supplier:

23.00 EUR (w/o VAT)
S2151
Code: S2151
On site: 1 pcs On site: 0 pcs

Supplier:

21.06 EUR (w/o VAT)
1482BP410
Code: 1482BP410
On site: 1 pcs On site: 0 pcs

Supplier:

197.34 EUR (w/o VAT)
497A
Code: 497A
On site: 1 pcs On site: 0 pcs

Supplier:

29.44 EUR (w/o VAT)
S2390
Code: S2390
On site: 1 pcs On site: 0 pcs

Supplier:

9.24 EUR (w/o VAT)
410YLW
Code: 410YLW
On site: 0 pcs On site: 0 pcs

Supplier:

19.64 EUR (w/o VAT)
S806CBL3
Code: S806CBL3
On site: 0 pcs On site: 0 pcs

Supplier:

34.57 EUR (w/o VAT)

Industrial Padlocks and LOTO Safety Locks for Hazardous Environments

This category includes heavy-duty security padlocks and dedicated Lockout/Tagout (LOTO) safety locks for industrial applications. Products are suitable for securing perimeter gates, tool cribs, electrical panels, valves, pneumatic circuits, and heavy machinery during maintenance or servicing operations. Master Lock is the primary brand represented, with over 100 years of engineering in security and safety locking systems, holding a strong position in both North American and European industrial markets.

Product Types and Key Technical Differences

FeatureProSeries Security PadlocksZenex LOTO Safety Locks
Primary purposeAsset protection, access controlHazardous energy isolation (LOTO)
Body materialSolid steel, solid brass, Xenoy™ thermoplasticZenex™ thermoplastic (non-conductive)
Shackle materialBoron-alloy or hardened steelSteel (non-magnetic variants available)
Operating temp.Standard industrial range-56°C to +176°C
Pin cylinder5–6 pin with spool pins (pick-resistant)6-pin (key-retaining mechanism)
Electrical safetyNot ratedNon-conductive, non-magnetic (dielectric)
Colour codingLimitedMultiple colours for worker identification
OSHA complianceNoYes — supports 29 CFR 1910.147

Technical Selection Criteria

When specifying padlocks for industrial use, evaluate the following parameters:

  • Body material: Thermoplastic (Zenex/Xenoy) for chemical, UV, and temperature resistance; aluminium for lightweight use in abrasive environments; stainless steel for corrosive or marine conditions.
  • Shackle specification: Boron-alloy or hardened steel for cut resistance; dielectric shackles for electrical isolation procedures.
  • Keying system: KD (keyed different — each lock has a unique key), KA (keyed alike — one key opens a group), or MK (master key — hierarchical access across groups or entire systems).
  • LOTO-specific features: Key-retaining mechanism (key cannot be removed unless lock is closed), high-visibility colour options, and compatibility with group lockout hasps and lockout stations.
  • Identification options: Laser engraving, adhesive labels, or personalised safety cards with employee name, photo, and authorisation level — critical for multi-shift and subcontractor environments.
  • Accessories: Group lockout hasps, cable lockouts (0.60 m to 15 m), valve and ball valve lockout devices, circuit breaker lockouts, plug lockouts, and lockout stations with or without covers.

Sourcing and Availability

Master Lock industrial safety locks and ProSeries padlocks are available as individual units, starter kits, or complete lockout stations configured for specific trades (electricians, maintenance supervisors, contractors). Custom keying systems, colour configurations, and engraved identification can be specified at order. Warning tags in industrial-grade polypropylene, rated for outdoor UV, chemical, and moisture exposure, are available pre-printed or fully customised. Contact our technical team to specify a keying hierarchy or configure a site-wide LOTO programme.

What is the difference between KD, KA, and MK keying systems in industrial padlocks?

KD (Keyed Different) means each padlock in the system has a unique key — standard for individual LOTO assignments where one worker controls one lock. KA (Keyed Alike) allows a single key to operate multiple locks within a defined group, useful for supervisors managing a specific zone. MK (Master Key) adds a hierarchical layer where a single master key can open all locks across groups or the entire system, while individual keys remain restricted to their assigned lock. For LOTO compliance, KD is typically mandatory at the worker level to enforce the one-employee-one-lock rule.

Are Zenex thermoplastic safety padlocks suitable for use on electrical isolation points?

Yes. Zenex thermoplastic padlocks are specifically designed as non-conductive and non-magnetic, making them appropriate for electrical LOTO procedures on switchgear, circuit breakers, and control panels. The body and shackle materials do not conduct electricity, reducing arc flash and shock risk during energy isolation. Always verify the specific dielectric rating against your site voltage levels and applicable EN/IEC standards before deployment.

What is the key-retaining mechanism in Master Lock LOTO padlocks and why does it matter for safety compliance?

The key-retaining feature prevents the key from being removed from the lock unless the shackle is fully closed and locked. This eliminates the risk of a worker leaving a lock in an open, unsecured state on an isolation point. From a compliance standpoint, it provides an auditable physical control ensuring that energy isolation cannot be inadvertently bypassed — a requirement under OSHA 29 CFR 1910.147 and equivalent European LOTO regulations.

Which Master Lock padlock body material should be specified for outdoor valve lockouts in chemically aggressive environments?

For outdoor applications with exposure to chemicals, moisture, and UV radiation, Zenex or Xenoy thermoplastic body padlocks are the preferred specification — rated from -56°C to +176°C and resistant to most industrial solvents and corrosives. Where mechanical abrasion is also a factor, aluminium-body variants offer additional structural durability. Stainless steel body padlocks with stainless shackles are the correct choice for marine or highly corrosive environments where metal integrity must be maintained long-term.