Fire Alarm Protocols Explained: Open, Closed and Managed Protocol Systems

fire alarm protocols closed open managed comparison

As a leading Fire Alarm Provider, Midland Fire Security Services are frequently asked what the difference is between different fire detection systems and protocols. We wanted to provide some clear information so that you can make an informed decision when choosing your Fire Alarm provider.

What is a Fire Alarm Protocol?

In fire detection systems a protocol is the language which allows communication between different devices. Sounders, call points and control modules etc. will need to communicate with the Fire Alarm Control Panel using the same protocol.

Typically these systems can be divided into three categories: Open Protocol, Closed Protocol and Managed Protocol

Closed Protocol Fire Alarm Systems

In a Closed Protocol System, the panel and devices are manufactured by the same company. Engineer functions can only be worked on by the manufacturer. System modifications or fault repairs would need to be carried out by the manufacturer directly.


  • Company working on system will be approved and have correct understanding helping meet legislative duties and requirements of BS5839.1 2017.
  • All components made by one manufacturer.
  • All software provided by one company.
  • All technical support & training provided by one company.
  • Software only supplied to trained personnel.
  • All faults must be down the manufacturer or Installer.


  • Lack of choice for consumers.
  • No options commercially, stuck with single supplier so costs tend to be higher for additions, call-outs, service and maintenance.
  • Life time cost of owning the system is higher in most circumstances.

Open Protocol Fire Alarm Systems

In an Open Protocol System, the panel and devices may be manufactured by different companies – as long as they are compatible. Equipment available to anyone via wholesalers and work can be carried out by any contractor.


  • Available for any contractor to carry out modifications and fault finding.
  • Lots of options commercially, so tends to be lower cost.


  • No training required, so no proof of competence.
  • Easy access to software can lead to untrained engineers working on systems.
  • Like all Analogue Addressable fire systems, once a manufacturers equipment is installed, only one equipment supplier can be used.
  • Panels can still be locked out so an end user can be tied to a single supplier.
  • Different manufacturers for panels & devices – when things do go wrong, more than one company may have to be involved to find a solution, software, etc.
  • End users are not always given full functionality of equipment.
  • May not have technical support from the manufacturer.

Managed Protocol Fire Alarm Systems

A Managed Protocol System is a middle ground between Open / closed protocols. Engineer functions can be provided by contractors but only with approval from the manufacturer. This helps ensure systems are set up correctly but gives the client freedom to choose their own contractor from a pre-approved list.


  • Any contractor / company working on the system will be approved and have correct training and expertise – helping meet legislative duties and requirements of BS5839.1 2017.
  • Choice from a wide selection of companies to work on the system.
  • Contractors will have 3rd party accreditations (such as BAFE) as a requirement for approval.
  • Commercially you have choice, usually a lot of options meaning competitive pricing.


  • Limited companies able to work on the system – But more than in a Closed Protocol System.

Can I use equipment from different providers Together?

Once a fire alarm system is installed the field of devices selected dictate that any additional replacement device must use the same protocol. Therefore, devices from other manufactures are not compatible when installed on the same addressable loop.

Does the protocol give freedom of choice?

Customers can choose any protocol for their fire alarm system however once the choice is made they are locked in to the performance of the fire alarm system using that protocol. To change from one protocol to another would involve replacing the entire system.

The most important factor is that the system chosen meets the required legal standards with the ability to expand if the business needs change.

Contact Midland Fire to arrange a free site survey

Midland Fire offer Open and Managed Protocol Systems from reputable manufacturers, giving customers more choice.

If you would like more information please call us on 01283 741000 or email: info@midlandfire.com