Most buildings have water-safety roles written down somewhere. There is a named duty holder, perhaps a responsible person, a water treatment contractor on a service contract, and site staff who open the building each morning. On paper it looks covered. In practice, tasks still slip through the cracks: the monthly temperatures stop being recorded after a staff change, a remedial action sits unactioned because each party assumed the other owned it, and nobody can say with certainty who signs off the annual review.
A RACI matrix is a simple way to close those gaps. It takes the roles you have already appointed and maps them, task by task, so that for every job there is no doubt about who does it, who answers for it, who must be asked, and who must be told. It is an organising tool, not a legal device, but it works well alongside the duties set out in the Approved Code of Practice and the governance expectations in BS 8680 [1][2].
What RACI means
RACI assigns four distinct relationships to each task:
- Responsible (R): the person or party who actually carries out the work. There can be more than one R on a task where the work is shared.
- Accountable (A): the single person who is answerable for the task being done correctly and on time. There should be exactly one A per task.
- Consulted (C): those whose input is sought before or during the task. This is a two-way conversation, not a notification.
- Informed (I): those who are kept updated on progress or completion. This is one-way.
The discipline comes from separating “does the work” from “answers for the work”. A contractor can be Responsible for sampling. That does not make the contractor Accountable for whether sampling happens at all.
A worked matrix for common tasks
The table below shows how typical water-safety tasks might map across common roles. Treat it as a starting template to adapt to your own site and contracts, not a fixed prescription. The exact allocation depends on who you have appointed and what your contracts say.
| Task | Duty holder | Responsible person | Deputy RP | Water treatment contractor | Site staff |
|---|---|---|---|---|---|
| Commission the risk assessment | A | R | C | C | I |
| Monthly temperature monitoring | I | A | R | C | R |
| Weekly flushing of low-use outlets | I | A | C | I | R |
| Routine sampling | I | A | C | R | I |
| Remedial works (e.g. removing dead legs) | A | R | C | R | I |
| Record keeping and logbook upkeep | I | A | R | C | R |
| Annual scheme review | A | R | C | C | I |
Reading across the “monthly temperature monitoring” row: the responsible person is Accountable for it happening, site staff and the contractor may both be Responsible for taking readings, the deputy supports delivery, the contractor is Consulted on method, and the duty holder is Informed through reporting. Every cell answers a question that, left unwritten, tends to produce the “I thought you were doing it” gap.
What nobody tells you: the A cannot be outsourced
Here is the point that often gets lost when a matrix is drawn up by committee. You can outsource the R. You cannot outsource the A.
It is straightforward to put a contractor’s name in the Responsible column for sampling, monitoring or remedial works, and that is exactly what contractors are for. The temptation is then to slide the Accountable letter across to them as well, on the reasoning that they are the experts and they are being paid. That is the move that quietly fails.
Accountability stays inside your organisation. It sits with the duty holder or the responsible person they appoint, because the legal duty to manage the risk rests with the person who has control of the premises and cannot be signed away through a contract [3]. Engaging a competent contractor is sensible and, for many sites, necessary. But if the contractor stops attending, mis-records a result, or quietly drops a task, the answer to “who was accountable?” is still you, not them. The ACoP is explicit that responsibilities must be appointed and clearly defined, and that competence must be assured for whoever holds them [1].
So when you build the matrix, apply one hard rule to every row: exactly one A, and that A is always a named individual within your duty-holding organisation. If a row has the A pointing at an external contractor, the matrix is describing a transfer that does not legally exist. Move the A back inside, and keep the contractor as the R.
This is also why BS 8680 frames clear allocation of roles as a governance matter for the water safety group rather than a paperwork exercise. Governance is about who answers for the system as a whole, with roles allocated explicitly in the water safety plan [2].
Building your own matrix
A few practical steps keep the exercise honest:
- List real tasks, not job titles. Break the work down to the level at which things actually go wrong: each monitoring activity, each record, each review and sign-off.
- Map roles to the people you have actually appointed. Use the structure of duty holder and responsible person roles as your backbone, then add deputies, contractors and site staff.
- Assign one A per row first. Do the accountability column before anything else. If two people both feel accountable, that is two people who can each assume the other has it.
- Fill in R, then C and I. Be sparing with Consulted: if everyone is consulted on everything, decisions stall.
- Embed it in the plan. The matrix belongs inside your water safety documentation, not in a separate file nobody opens. See developing a comprehensive water safety plan for where it fits.
- Review it when people change. A RACI matrix dates the moment someone leaves. Revisit it at each scheme review and after any staffing or contractor change.
Where the matrix sits legally
A RACI matrix is an organising and communication tool. It is not itself a legal requirement, and completing one does not, on its own, discharge any duty. What the law and guidance require is that responsibilities are appointed and clearly understood, that those holding them are competent, and that the risk is actually managed [1][3]. A matrix simply makes those requirements visible and harder to fudge. The relationship between good practice and the legal minimum is worth understanding in its own right, as covered in water safety plans: best practice vs legal requirement.
Used well, the matrix turns a list of names into a working map of who does what, so the next staff change or contract handover does not reopen the same gaps.
Frequently asked questions
What does RACI stand for in water safety?
RACI stands for Responsible, Accountable, Consulted and Informed. Responsible is the party that carries out a task, Accountable is the single person answerable for it, Consulted are those whose input is sought, and Informed are those kept updated. Applied to water safety, it maps each control task against your appointed roles so that responsibilities are clearly defined, which the ACoP expects [1].
Can I make a contractor accountable for Legionella control?
You can make a contractor Responsible for carrying out tasks such as sampling or remedial works, but accountability generally stays with the duty holder or responsible person. The legal duty to manage the risk rests with whoever has control of the premises and is not transferred by a service contract [3]. Engaging a competent contractor is encouraged, but it does not move the A in your matrix outside your organisation.
How many people should be accountable for one task?
Exactly one. The strength of RACI comes from having a single Accountable person per task, so there is never ambiguity about who answers if the task is missed. Multiple people sharing the A tends to recreate the very gap the matrix is meant to close, where each assumes the other is handling it.
Is a RACI matrix a legal requirement?
No. A RACI matrix is a voluntary organising tool, not a legal requirement, and completing one does not by itself discharge any duty. What is required is that responsibilities are appointed, clearly defined and held by competent people, and that the risk is actually controlled [1][2]. The matrix is a practical way to demonstrate and maintain that clarity.
Sources
- HSE, Approved Code of Practice and guidance L8, Managing the risk: management responsibilities, training and competence, p.14. https://www.hse.gov.uk/pubns/books/l8.htm
- BSI, BS 8680:2020 Water quality: Water safety plans code of practice, clause 4.2 Governance. https://knowledge.bsigroup.com/products/water-quality-water-safety-plans-code-of-practice
- HSE, Health and Safety at Work etc. Act 1974, general duties of employers and persons in control of premises. https://www.legislation.gov.uk/ukpga/1974/37/contents