Sam Jackman, Co-CEO at Shared Access, explains why mobile connectivity should be considered right from the design stage of a building to ensure the safety of workers
Imagine a maintenance engineer working alone in the basement of a large office building. They have an accident or suddenly become unwell and need assistance. They reach for their mobile phone, only to find there is no signal. It’s a scenario that raises an important question for anyone responsible for managing a building. Do you know where people can and cannot make a mobile call on your premises?
We usually talk about poor mobile coverage as an inconvenience. Calls dropping out during meetings, messages not arriving or the frustration of having to walk outside to speak to someone. But in some circumstances, being unable to communicate can have much more serious consequences.
We spend considerable time making buildings safer, from fire protection and access control to surveillance systems and emergency procedures. Yet, I’m not convinced we always give the same attention to whether people can reliably communicate from every area where they might need help. This matters particularly for people working alone.
The places we tend to overlook
When building owners think about mobile coverage, they’re understandably concerned about the areas their tenants and visitors use most frequently. Reception areas, offices, meeting rooms and shared spaces are usually the first places where poor reception becomes apparent. But what about the areas people don’t routinely visit?
Basement plant rooms, underground car parks, service corridors, and back-of-house facilities are all essential to the operation of a commercial building. They are also places where engineers, cleaners, security personnel, and maintenance contractors may work without anyone else nearby. Unfortunately, they are often among the most difficult environments for mobile signals to penetrate.
Concrete, steel, and other building materials can significantly weaken mobile signals. Underground locations present an obvious challenge, but coverage can also be affected by the specialist glazing and insulation used in modern energy-efficient buildings. Ofcom’s Connected Nations 2025 report acknowledges that indoor coverage can vary considerably depending on building materials, wall thickness, and even where someone is standing. It’s entirely possible to have excellent mobile reception on the street outside, or even on the upper floors of a building, while having little or no usable signal elsewhere.
There’s another complication. Coverage can vary considerably between mobile operators. Just because one person’s phone works in a particular location doesn’t mean everybody else’s will. For a building owner, this means that a few successful phone calls from reception are not sufficient evidence that mobile coverage is reliable throughout the property.
What does this mean for lone workers?
Lone working is more common in buildings than we might initially assume.
A cleaner working outside office hours, a security officer patrolling an underground car park, or an engineer checking equipment in an isolated plant room may all be working without direct supervision.
The Health and Safety Executive’s guidance on lone working is clear: employers must assess the risks and maintain contact with workers. It also advises regularly testing communication systems and emergency procedures to ensure they are effective. Reliable communication is fundamental to those arrangements. Yet how many employers know whether their staff can make a mobile call from every part of the building in which they work? And how many building owners have assessed the coverage available in basements, plant rooms, and other areas where people may be working alone?
Nor should we assume that an emergency call will always connect simply because a phone may be able to access another operator’s network. Emergency calling depends on there being a suitable network signal available in the first place. For me, this is where mobile connectivity needs to become part of the wider conversation about building safety rather than being treated solely as an occupier amenity.
What about people’s lives outside work?
There’s another aspect of reliable mobile connectivity that I think deserves more attention. People don’t stop being parents, carers, or family members when they walk into their workplace. What happens when a school needs to contact a parent because their child has had an accident? Or when a care home needs to reach someone urgently about an elderly relative? These aren’t business communications, but they matter enormously to the people involved.
Many employers restrict personal devices from accessing their corporate Wi-Fi networks for security reasons. It’s another reminder of why employees should have reliable mobile coverage in their workplace, independently of the organisation’s IT infrastructure.
I don’t think we should underestimate the reassurance that comes from knowing someone can reach you if something important happens at home.
Who is responsible?
One of the difficulties is that several different organisations may be involved in managing the risks associated with a building. The landlord owns the asset. A facilities management company may operate it. Individual occupiers employ people within it, while external contractors undertake maintenance, cleaning, and specialist engineering work. Each has different responsibilities and it’s important not to confuse them.
An employer has duties towards its workers, including those working alone. A building owner or operator has responsibilities relating to the premises and risks under its control. Contractors also need to understand the environments in which their employees will be working.
The problem arises when everybody assumes somebody else has checked the communications infrastructure. An employer might reasonably expect a modern commercial building to have mobile coverage. A landlord might assume, wrongly, that mobile operators will provide the coverage needed throughout the property. A facilities manager may not discover the extent of the problem until an employee or contractor raises a concern.
Mobile networks are designed to provide coverage across wide geographical areas. They cannot always deliver the level of indoor coverage required by a particular building, especially in underground or heavily shielded locations.
Where those limitations exist, building-specific infrastructure is needed.
Start by finding out where the gaps are
For building owners and facilities managers, the first step is relatively straightforward: understand the mobile coverage you actually have. That means assessing more than the offices and other heavily occupied spaces. Plant rooms, basements, underground car parks, stairwells, and service corridors should all be considered, particularly where people may be working alone or need to call for assistance.
Professional mobile coverage surveys can identify weak-signal areas, assess performance across different mobile networks, and establish where improvements are needed.
The results should inform discussions between building owners, facilities managers, employers and contractors, particularly where poor reception could prevent someone from calling for help.
Where coverage gaps are identified, the next step is to determine what in-building mobile infrastructure is needed to address them. Depending on the size, construction and layout of the property, this might involve relatively straightforward improvements or a more comprehensive system designed to deliver reliable coverage across multiple mobile networks.
A small office will have different technical requirements from a large, multi-storey building with extensive underground facilities, but the principle should be the same: people should be able to make and receive mobile calls wherever they are in the building.
This shouldn’t be a one-off exercise. As buildings change and mobile networks evolve, coverage needs to be monitored and maintained to ensure it continues to meet the needs of the people using the space.
Don’t leave it until the building is occupied
For new developments and major refurbishments, mobile coverage needs to be considered at the design stage alongside other essential building infrastructure.
Understanding how construction materials might affect reception, identifying potential problem areas such as basements and underground car parks, and allowing space for the necessary cabling and equipment can make installation considerably easier and less disruptive.
Yet mobile connectivity is still too often addressed once a building is occupied and people start complaining about poor reception. By then, the opportunity to incorporate the necessary infrastructure during construction has passed, potentially making improvements more complicated and costly.
Of course, existing buildings shouldn’t be overlooked. Mobile coverage can be improved in occupied properties and, where blackspots exist, building owners should take steps to address them rather than accepting poor reception as an unavoidable characteristic of the property.
Mobile connectivity is essential building infrastructure
Reliable mobile coverage should be a basic expectation in any modern building, not something that only receives attention when occupiers complain or a problem arises.
For building owners, developers and facilities managers, my advice is to make mobile connectivity part of the conversation about operational risk. Ask where people work alone. Establish how they are expected to communicate. Check whether those arrangements work in practice. And where gaps exist, make sure somebody takes responsibility for resolving them.
We’re increasingly good at designing buildings that are efficient, intelligent, and attractive to occupiers. We should be equally confident that the people responsible for keeping those buildings running can call for help when they need it.
We also shouldn’t overlook the importance of people being contactable when something happens beyond the workplace. Sometimes, the most important test of a building’s connectivity isn’t how quickly someone can download data – it’s whether they can make or receive a call when it really matters.
Please note, this article will also appear in the 28th edition of our quarterly publication.
