Sysmatics
info@sysmatics.co.uk Email Us
Process Services Service Request Legionella Schematics Case Studies About
info@sysmatics.co.uk
Specialist service

Legionella schematic drawings for L8 & HSG274 risk assessments.

Outsourced schematic production for UK risk assessment companies, water hygiene contractors and FM providers. You send the survey — we return a clear, accurate, report-ready schematic of the water system.

Request a Quote Email info@sysmatics.co.uk
The requirement

Why every Legionella risk assessment needs a schematic

Under the Approved Code of Practice Legionnaires' disease: The control of legionella bacteria in water systems (ACOP L8) and the supporting HSE guidance HSG274, a suitable and sufficient risk assessment must describe the water system it covers — and that description is expected to include an up-to-date schematic diagram.

The guidance is explicit that a site survey of the water systems should be carried out, including an asset register of the associated plant, and that this should be accompanied by a current schematic showing the layout of the system — including any parts temporarily out of use, since intermittently used sections and dead legs are exactly where unnoticed microbial growth occurs.

HSG274 also lists the validity of the schematic as one of the things an assessor should check: the drawing needs to cover all parts of the system where water may be used or stored. A schematic that is missing, out of date, or unreadable is a recurring weakness in assessment files.

ACOP L8 describes schematic diagrams as not formal technical drawings — they are intended to be read without specialist training, giving someone unfamiliar with the site a quick understanding of the relative positions and connections of the relevant components. Paraphrased from ACOP L8 (4th edition), paragraph 40, and HSG274 Part 2.

That distinction is the whole design brief. A Legionella schematic is not an architectural drawing and not a scaled services layout. It is a communication tool — and it succeeds or fails on whether a responsible person, a contractor or an inspector can follow the water through the building without needing the drafter to explain it.

Drawing content

What we show on every schematic

We draft from your survey data to reflect the system as found. Typical content, adapted to the site and to your house standard:

  • Incoming mains supply and point of entry
  • Cold water storage tanks, with capacity and location noted
  • Calorifiers, water heaters and combination units
  • Hot water flow and return circuits, including subordinate loops
  • Cold water distribution and risers by floor or zone
  • Near and far sentinel outlets identified for monitoring
  • Thermostatic mixing valves (TMVs), showers and spray outlets
  • Isolation, regulating and drain valves
  • Pumps, strainers, filters and softeners
  • Dead legs, blind ends and sections out of use, clearly flagged
  • Outlet counts by room or area where required
  • Key, legend, revision block and drawing reference

Systems we draw

  • Hot and cold water services (HSG274 Part 2)
  • Evaporative cooling systems and cooling towers (Part 1)
  • Other risk systems — spa pools, humidifiers, air washers, vehicle washes, water features (Part 3)

Building types we handle

From single-tank commercial units through to complex, multi-riser estates.

  • Offices, retail and hospitality
  • Schools, universities and public buildings
  • Residential blocks and student accommodation
  • Healthcare and care settings, where vulnerable occupants raise the stakes
  • Industrial sites and multi-block estates
How it works

Send the survey. Get the drawing back.

No new software for your assessors to learn and no change to how they work on site.

1

You survey

Your assessor surveys the site as normal — asset lists, field notes, photographs, marked-up floor plans or an existing outdated drawing.

2

We draft

We produce the schematic to your house style, so drawings across your portfolio stay visually consistent regardless of who surveyed.

3

You review

You check it against the survey and mark up anything that needs adjusting. Revision rounds are included in your service tier.

4

We issue

Final drawing supplied as PDF, JPG/PNG or editable DXF, referenced and revision-numbered, ready to drop into your report.

Formats and revisions

PDF
Report-ready, print-accurate, the usual choice for issuing with an assessment.

Image (JPG/PNG)
For embedding directly into report templates, portals and log books.

DXF / editable CAD
So your own team can update the drawing as the system changes, without coming back to us.

Because water systems change, we keep your source files so revisions after remedial works, dead-leg removals or system modifications are quick and inexpensive rather than a redraw from scratch.

Why outsource

Assessors assess. We draw.

Drafting is slow, repetitive work that pulls qualified assessors away from chargeable site time. Handing schematic production to a dedicated drawing office removes that bottleneck without adding permanent headcount.

  • Faster reports — drawings are produced in parallel while the assessment is written.
  • Lower cost per drawing than in-house production time.
  • Consistency across your whole portfolio, however many assessors you field.
  • Scalable capacity for tender wins and seasonal peaks without hiring.
  • White-label — drawings carry your title block and branding, not ours.

Start a service request

Sysmatics drafter producing a technical schematic drawing
Questions

Frequently asked questions

About Legionella schematic drawings and how we work.

What must a Legionella schematic drawing show under HSG274 Part 2?
A useful schematic identifies all the water system components relevant to legionella risk: cold water storage tanks (CWST), calorifiers and water heaters, thermostatic mixing valves (TMVs), recirculating hot water loops, dead-legs and little-used outlets, incoming mains, sentinel points and system zoning. It should show flow direction and allow someone unfamiliar with the site to understand the whole system at a glance. HSG274 Part 2 treats the schematic as a description of the system rather than a formal technical drawing, and we produce ours to that standard.
Are Legionella schematic drawings a legal requirement?
ACOP L8 has special legal status: follow it and you are doing enough to comply with the law; depart from it and you must show you have complied in some other way. It states that the risk assessment should include an up-to-date schematic diagram showing the layout of the plant or system, including parts temporarily out of use. HSG274 also lists checking the schematic's validity among the assessor's tasks. In practice an assessment without a current schematic is difficult to defend. The duty sits with the dutyholder and the assessor; our role is to produce the drawing.
What survey information do you need to produce a schematic?
We work from marked-up floor plans, site photographs, handwritten notes, asset registers or a site visit report. You do not need to supply a finished CAD drawing. The more detail the better: location and type of tanks, pipe sizes and materials, isolation points, TMV locations, redundant outlets and dead-legs, and building zones. Where something is unclear or looks contradictory we raise a query rather than guessing.
What is the typical turnaround time?
Standard turnaround is around 5 to 7 working days from receipt of complete survey information. Rush production within 48 hours is available on request, and recurring programmes can be placed on an ongoing rolling schedule. Turnaround depends on the clarity and complexity of the survey, so more detailed input generally means faster output. Exact timescales are confirmed with your quote.
What file formats do you provide?
Drawings are delivered as PDF, image (JPG/PNG) and DXF or DWG editable CAD, chosen per requirement. Editable CAD lets you import the drawing into your own environment to annotate or maintain it as the system changes; PDF and image formats drop straight into reports and log books. All formats are suitable for inclusion in risk assessment documents and written schemes of control.
Does Sysmatics carry out Legionella risk assessments or remedial works?
No. Sysmatics is an outsourced drafting partner and we produce schematic drawings only. We do not carry out risk assessments, sampling, testing or remedial works. ACOP L8 requires that the person carrying out the risk assessment is competent to do so, and that responsibility stays with your assessor. We convert your survey data into clear, standards-aligned drawings that support your assessment and compliance documentation.
Can you update an existing schematic instead of redrawing it?
Yes. Updating after remedial works, dead-leg removal or system changes is routine. If we produced the original we hold the source file, which makes revisions quicker and cheaper than a redraw. We can also rebuild legacy or inherited drawings into a consistent modern format.
Will the drawings carry our branding?
Yes. We work white-label by default: your title block, your drawing numbering convention and your house drawing standards, so the output is indistinguishable from in-house production.
How is our client and site data protected?
Survey data and drawings are used solely to produce your deliverables, handled confidentially and issued back to you. We do not redistribute client material or use it as portfolio content without written permission. See our Privacy Policy for detail.
Get started

Send us a survey and see the difference.

Happy to produce a sample drawing from one of your existing surveys so you can judge the quality before committing to a programme.

Request a Quote info@sysmatics.co.uk

Note: references on this page to ACOP L8 (Legionnaires' disease: The control of legionella bacteria in water systems, 4th edition) and HSG274 Parts 1–3 are provided for context only and are paraphrased from the published HSE documents. They do not constitute legal or compliance advice. Dutyholders and risk assessors should refer to the current published guidance at hse.gov.uk/legionnaires. Sysmatics Ltd produces drawings to support the assessment process; it does not carry out Legionella risk assessments.