BS6173 and DW172 Checklist

DW172 & BS6173: A Simple Checklist for Commercial Kitchen Extract

If you work around commercial kitchens, you’ve probably heard DW172 and BS6173 mentioned a lot. They’re not just box-ticking standards - they’re what keep kitchen extract systems safe, compliant, and actually fit for purpose.

The problem is, they can feel a bit heavy when you’re just trying to sense-check a job or move a project forward.

So here’s a straightforward way to look at it.

What are DW172 & BS6173 (in plain terms)?

• DW172 is all about how your kitchen extract system is designed and built - airflow, ductwork, grease control, cleaning access, all of that.

• BS6173 focuses on safety, particularly gas interlocks and making sure extraction is working properly before cooking equipment can run.

Together, they cover performance and safety - both need to be right.

A Simple Checklist to Run Through

When you’re looking at a project - whether it’s early design or reviewing something already installed — these are the key things worth checking:

1. Canopy design & coverage

Is the canopy actually sized and positioned correctly for the cooking equipment?
If it’s too small or poorly placed, everything else struggles.

2. Airflow rates

Are you moving enough air for the cooking duty?
Heavy-duty cooking (chargrills, fryers, wok burners) needs more extraction than light use.

3. Grease filtration

Are proper grease filters in place and suitable for the application?
This is a core part of DW172 - and it directly affects fire risk and system performance.

4. Access for cleaning

Can the system actually be cleaned?
Access panels, removable sections, and sensible routing matter more than people think.

5. Fire safety / interlocks (BS6173)

Is there a gas interlock in place?
Does the system prove airflow before allowing gas to the appliances?
This is a big one for compliance and safety.

6. Discharge location

Where is the air actually going?
If the outlet is poorly positioned, you’ll likely run into odour complaints or planning issues.

7. Odour control

Do you need it - and if so, is it suitable?
City centres, basements, or tight sites usually need additional filtration like ESP, carbon, or UV.

8. Ductwork design

Is the ductwork sized correctly, routed sensibly, and accessible?
Long runs, sharp bends, and no access = problems later.

9. Planning & site constraints

Are there local authority requirements or restrictions?
Things like discharge height, proximity to neighbours, and noise can all come into play.

Why this matters (beyond compliance)

A lot of issues we see aren’t because people ignore standards - it’s because things get missed early on.

That usually leads to:

• Costly changes later

• Planning pushback

• Odour complaints

• Systems that just don’t perform properly

Running through a simple checklist like this early on can save a lot of time and hassle.

You don’t need to overcomplicate DW172 and BS6173.

If the system is:

• Capturing properly

• Moving enough air

• Safe to operate

• Easy to maintain

• And not causing issues outside the building

…you’re on the right track.