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Master Suite System FAQ

Get clarity on master suite systems with this FAQ from your local Brookwood locksmith – we've got your security needs covered.

Common Master Key System Questions

What is a master key system?

A master key system is a hierarchical locking system where multiple locks can be opened with a single "master key," while individual keys exist for specific locks. This system allows for tiered access control.

Why would I need a master key system?

Master key systems simplify key management, especially in facilities with numerous locks and different access needs. They reduce key clutter and make it easier to control who can access which areas.

Who uses master key systems?

They are ideal for various facilities, including hospitals, schools, businesses, and residential properties. Anyone managing multiple locks and varying access levels can benefit.

How do master key systems work with different access levels?

In a master key system, there are individual keys for specific locks (also known as 'differs') and master keys that open multiple locks. Sub-master keys may also be used for groups of locks. For example, a cleaner might have a key to access only cleaning cupboards while a supervisor has a sub-master key to access several different room on a floor and the manager has the master key to access the whole building.

Restricted vs. Non-Restricted Master Key Systems

What is a restricted master key system?

A restricted system offers enhanced security by controlling key duplication and distribution, requiring authorisation from an 'authorised key signatory' to create new keys.

How does a restricted system work?

A restricted system utilises unique pinning configurations. Key duplication is controlled and requires authorisation from the 'authorised key signatory'. 'Differs' key individual locks, while master and sub-master keys open multiple locks.

What are the benefits of a restricted system?

Enhanced security, control over key duplication, peace of mind, and tailored access levels are key benefits of this system. These are all especially important for sensitive areas and organisations where security is paramount

What is a non-restricted master key system?

A non-restricted system also uses the concept of master and individual keys, however it does not control key duplication, meaning anyone can get a copy of the key cut.

Why choose a non-restricted system?

Non-restricted systems are ideal for customers who want the organisational benefits of master key access but do not require tight control over key duplication, for example in a small office or personal residence. Keys are easy to get cut when extra keys are needed.

What is the difference between a restricted and non-restricted system?

The crucial difference is key duplication control. Restricted systems prevent unauthorised duplication, while non-restricted systems do not.

EVVA EPS Master Key Systems

EVVA Access to Security Logo

What is EVVA EPS?

EVVA EPS is a patented, high-security locking system that's designed and engineered for customised access control. It's a pin-based system with multiple security layers.

What are the advantages of EVVA EPS?

EVVA EPS offers high security, patented key profile, customisable configurations, modular design, and flexibility. Key duplication is carefully controlled.

How does the EVVA EPS system differ from other master key systems?

EVVA EPS offers a patented profile, preventing unauthorised key duplication. It allows for granular control and customised access levels, including tailored sub-master keys.

What is the 'patented, multiple-overlap key profile' in EVVA EPS?

This refers to the unique key design that prevents standard key-cutting machines from making copies. It's a crucial security feature.

What is a security card in the EVVA EPS system?

The security card is required for the authorisation of duplicate keys for the restricted system, providing an added level of control.

What are the active and additional scanning positions in an EVVA EPS cylinder?

These are internal security components within the cylinder that check key authorisation. They comprise of five active scanning components and up to 20 additional scanning positions.

What is the modular system of EVVA EPS?

This allows us to adjust cylinder lengths or assign a particular function to cylinders making the system flexible and customised to the clients needs.

Is the EVVA EPS system fire-rated?

Yes, EVVA EPS cylinders comply with EN 1303:2005 in lock security class 6 and attack resistance class 2. They are also suitable for EI 30 and E 30 fire and smoke control doors.

What is the TS07 3-star optional variant of EVVA EPS?

The TS07 3-star variant is a high-security option that meets a high security specification to protect against lock snapping. You can order EPS keys in this configuration from our workshop.

Key Cutting & Ordering

How are keys cut for a restricted EVVA EPS system?

Keys for restricted systems are cut from code, and require authorisation from a named key signatory listed on the systems security card.

Where can I get restricted EVVA EPS keys cut?

Typically, restricted section keys can only be cut by either the locksmith who owns the lock system or the lock manufacturer themselves. Other locksmiths or key cutting services are not authorised to cut restricted section keys outside of their own systems. This tight control helps maintain the integrity of the security system as well as ensuring keys are only handled by trusted and experienced locksmiths.


At OC Services we retain control over the production and distribution of keys for our master suite systems. All keys are cut at our Brookwood showroom by our experienced locksmiths. This provides a convenient and secure way to get duplicate keys for your system. 

Can keys for EVVA EPS restricted system be ordered remotely?

Yes, with authorisation from a key signatory, we can receive written requests via email or post. Once the request has passed the verification process, keys will be cut and posted directly to the named recipient.

Where can I get non-restricted Evva EPS keys cut?

Non-restricted keys can be cut by any reputable locksmith, however it advisable to contact the company named on the key in the first instance.

Benefits of Master Key Systems 

What are the overall benefits of a master key system?

Benefits include: streamlined key management, enhanced security (especially with restricted systems), reduced key clutter and customised access control.

How can a master key system provide peace of mind?

A restricted master key system offers peace of mind thanks to the control over key duplication and the security it offers.

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