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)
3MKGRN
Code: 3MKGRN
On site: 0 pcs On site: 0 pcs

Supplier:

19.13 EUR (w/o VAT)
A1107KABLK
Code: A1107KABLK
On site: 0 pcs On site: 0 pcs

Supplier:

33.94 EUR (w/o VAT)
A1165BLU
Code: A1165BLU
On site: 0 pcs On site: 0 pcs

Supplier:

29.57 EUR (w/o VAT)
3MKLHGRN
Code: 3MKLHGRN
On site: 0 pcs On site: 0 pcs

Supplier:

23.42 EUR (w/o VAT)
3MKBLU
Code: 3MKBLU
On site: 0 pcs On site: 0 pcs

Supplier:

19.13 EUR (w/o VAT)
K1
Code: K1
On site: 0 pcs On site: 0 pcs

Supplier:

3.26 EUR (w/o VAT)
A1107KABLU
Code: A1107KABLU
On site: 0 pcs On site: 0 pcs

Supplier:

33.94 EUR (w/o VAT)
A1165BRN
Code: A1165BRN
On site: 0 pcs On site: 0 pcs

Supplier:

29.57 EUR (w/o VAT)
3MKLHBLU
Code: 3MKLHBLU
On site: 0 pcs On site: 0 pcs

Supplier:

23.42 EUR (w/o VAT)
2940EURDLH
Code: 2940EURDLH
On site: 0 pcs On site: 0 pcs

Supplier:

19.21 EUR (w/o VAT)
K15
Code: K15
On site: 0 pcs On site: 0 pcs

Supplier:

3.26 EUR (w/o VAT)
8413CBL13
Code: 8413CBL13
On site: 0 pcs On site: 0 pcs

Supplier:

48.75 EUR (w/o VAT)
A1107KABRN
Code: A1107KABRN
On site: 0 pcs On site: 0 pcs

Supplier:

33.94 EUR (w/o VAT)
A1165CLR
Code: A1165CLR
On site: 0 pcs On site: 0 pcs

Supplier:

29.57 EUR (w/o VAT)
3MK
Code: 3MK
On site: 0 pcs On site: 0 pcs

Supplier:

18.69 EUR (w/o VAT)
K17
Code: K17
On site: 0 pcs On site: 0 pcs

Supplier:

3.26 EUR (w/o VAT)
A1107KACLR
Code: A1107KACLR
On site: 0 pcs On site: 0 pcs

Supplier:

33.94 EUR (w/o VAT)
A1165GRN
Code: A1165GRN
On site: 0 pcs On site: 0 pcs

Supplier:

29.57 EUR (w/o VAT)
K1RSV
Code: K1RSV
On site: 0 pcs On site: 0 pcs

Supplier:

3.26 EUR (w/o VAT)
A1107KAGRN
Code: A1107KAGRN
On site: 0 pcs On site: 0 pcs

Supplier:

33.94 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.