Matthew Holliday, NSI’s Director of Technical Services & Field Operations, explains why false alarms from intruder systems are resurging.

A challenge faced by the security industry 30 years ago has recently re-emerged – false alarms from intruder systems.

Back in the mid-’90s this had become a serious concern.

Yet despite being successfully resolved by industry-wide action at the time, the past 18 months has seen a fresh increase in false alarms being erroneously referred for police response, largely due to technical vulnerabilities in dual path signalling systems.  

These systems, using primary and backup signal paths, help Alarm Receiving Centre (ARC) operators to verify alarm activations before alerting the police.

However, the recent rise in concurrent signal path failures has placed significant pressure on the police and insurers, as well as ARCs which monitor the ‘Type A’ remotely generated signals received from these dual path systems.   

End user customers can also be adversely affected if the intruder alarm system protecting their site or premises exceeds the current limit on false alarms prescribed by the National Police Chiefs’ Council’s (NPCC) requirements for security systems, namely two false activations received by the police in a rolling 12-month period.

A third activation within that timescale swiftly results in the demotion of Type A systems from ‘Level 1 – Immediate’ police response to ‘Level 3 – Withdrawn’.

This exposes sites to increased risks and potential insurance costs, since they must then rely on keyholder-only response for a minimum of 90 days.

During this period various NPCC conditions, including the upgrade of systems to meet current standards and passing of compliance checks e.g. an NSI Certificate of Compliance, must be met before the alarm system can be restored to ‘Level 1’ police response.   

Why false alarms are reoccurring? 

The widespread use of GSM (Global System for Mobile Communications) technology by alarm system installers is a key factor behind this false alarms issue.

Wireless 2G, 4G and 5G technologies are a popular choice for installers, given their cost-effectiveness, ease of installation and reliable performance as a transmission medium.    

However, reliance on GSM radio for both signalling paths is a significant cause of false alarms, especially in remote locations, where GSM base stations are often sparsely distributed, increasing the likelihood of communication failures.  

IP-based communications for broadband have also contributed to the problem.

While IP technology enables high-speed data transfer, it lacks the reliable, ‘always on’ connectivity required for alarm signalling.

With analogue PSTN lines being phased out by early 2027, many installations are switching entirely to IP protocols, which are more susceptible to short-term outages and require constant on-site power.

These changes reduce reliability when compared with more robust PSTN or copper wire systems, which are remotely powered by landline phone exchanges.  

In these situations, ARCs often err on the side of caution, interpreting IP-related outages as potential tampering or sabotage of the alarm signalling path rather than temporary technical or communication issues.

This cautious approach has led to a sharp increase in line fault failures being mistakenly flagged for police response.

As a result, police, insurers and ARCs are experiencing significant strain, with ARC operators dedicating disproportionate time to managing these false alarms.  

To address this recurring challenge, a multifaceted approach is essential.

This includes conducting site-specific risk assessments, implementing improved maintenance procedures and adopting tailored technology solutions.

The limitations of a ‘one-size-fits-all’ approach to signalling have become evident, underscoring the urgent need for adaptable solutions designed to meet the unique requirements of each site.  

Industry task force action  

To tackle the issue, an industry-wide task force including NSI, police, insurers, ARCs, trade associations and other stakeholders is developing best practices to guide installers.

The group plans to release new guidance by January 2025, offering practical solutions such as the deployment of extended radio aerials and high-gain antennae to help overcome location-specific signalling limitations.

It will also outline procedures to mitigate radio frequency interference, which can compromise radio signalling paths and lead to false alarms.   

This guidance could form the basis of a broad industry agreement, enabling its rapid adoption across the sector.

It will also act as an interim measure while relevant standards and codes of practice are updated to incorporate these solutions.

Key standards under consideration include BS 8243:2021, which covers the design, installation and configuration of Intruder and Hold-up Alarm Systems designed to generate confirmed alarm conditions; and PD 6662:2017, which incorporates a series of European BS EN 50131 alarm product standards, along with system requirements from BS EN 50131-1 for Intrusion and Hold-Up alarm systems.  

Third-party inspection  

Once adopted the new guidance is likely to become an essential element of inspection processes conducted by NSI and other certification bodies.

This includes both the initial approval of service providers and the annual surveillance audits required to maintain third-party certifications.

These independent audits provide reassurance to security system buyers and specifiers, verifying their NSI-certified providers consistently meet the high standards of professionalism and competence demanded by customers and other stakeholders.  

NSI is keen to highlight the important role certified alarm installers play in reducing false alarms caused by line faults and encourages them to collaborate closely with equipment suppliers and manufacturers to address dual path signalling issues.

Resolving these issues requires a unified effort across the entire industry, with the effective implementation of solutions standing to benefit all parties.  

Back to the future  

Reducing false alarms has been an industry priority for the past 30 years, with major advances achieved since the introduction of the landmark 1995 ACPO Intruder Alarm Policy, the precursor to today’s NPCC security systems requirements.

By 2020, over 1.1 million false alarm calls to police had been eliminated, despite the number of registered alarms increasing during the same period by 796,078 (source: Secured by Design).   

Interestingly, line faults were also a significant issue in 1995, prompting severe penalties for installations with recurring issues.

At that time, just two faults within a 12-month period could result in an alarm being downgraded to ‘keyholder response only’ status.  

Today’s industry challenges with dual path signalling echo those earlier obstacles, highlighting the need for a similar proactive and coordinated approach.

By updating standards and working collaboratively the industry can arrest this recent setback in false alarms, while maintaining the trust of police, insurers and buyers alike.  

This article was originally published in the January 2025 Edition of Security Journal UK. To read your FREE digital edition, click here.