Fire detection is a specialism that overlaps with electrical work without being the same trade. An excellent electrician can be entirely competent at the wiring and not competent to decide a category, position a detector or sign a commissioning certificate. The distinction matters because the paperwork they produce is what your compliance rests on.
What the work actually involves
Designing to a category, selecting detector types for each space, siting devices against the standard's rules, programming cause and effect, commissioning the installation and issuing certificates that a third party will later rely on. The physical installation is the least specialised part. The judgement calls before and the paperwork after are what the specialism consists of.
How competence is evidenced
Third party certification schemes audit firms against published scheme documents for named activities, and publish who holds what. That is the checkable evidence. Individual engineers may also hold qualifications and scheme cards. Neither guarantees a good job, but a firm with no certification for the activity you are buying has nothing independent standing behind its certificate.
The four questions
Which category and grade is this system, and who decided. Are you certificated for the activity you are quoting for, and can I see the scope. What certificate will I hold at the end, and what will it say if defects remain. Who holds the cause and effect matrix. A firm that answers all four plainly is one that has done this before.
When you need a designer rather than an installer
A new system, a change of use, a subdivision or a building that has grown needs somebody to decide the category before anybody prices devices. Asking three installers to quote without a design produces three different systems at three prices that cannot be compared. Paying for the design first is usually cheaper than the difference between those quotes.
Questions people ask about fire alarm engineer
Can my electrician install a fire alarm?
They may be competent to install the wiring while not being competent to design the system or commission it. The certificates that matter are design and commissioning, so check who will sign those.
What certification should a fire alarm engineer have?
Look for third party certification of the firm for the specific activity, design, installation, commissioning or maintenance, and check it on the certification body's own register rather than on the website.
Do I need a separate designer?
For new work, a change of use or a significantly altered building, yes. Without a design there is no category, and without a category nobody can say whether the installed system is right.