Short answer: A narrow gap can be worse than no gap because it admits grease and food but not a hand, brush, panel or inspection view. Either close it hygienically or make it genuinely accessible.
A 20–80 mm void catches grease but cannot accept a hand, brush or removable panel. The common misconception is that any gap satisfies cleaning access. This article turns that assumption into specific checks that can be recorded on the drawing, survey or commissioning sheet.
Model-specific rule: Do not publish a universal ‘minimum cleanable gap’; use the exact task and local food-safety requirements. Where gas, electricity, refrigeration, guarded components, hot oil, pressure or safety controls are involved, use the appropriately competent engineer and never bypass a safety device.
The dead-gap problem
Small voids beside fryers, ovens and counters collect aerosol, crumbs and wash water. The surface may be visible at the front while contamination remains along the full depth.
- Inspect the deepest point, not the front edge.
- Test the chosen brush or tool.
- Check whether a removable part must pass through the gap.
Choose closure or access
A hygienic closure must tolerate heat, movement and cleaning. An access gap must be large enough for the task and must not conflict with the manufacturer’s service or ventilation requirement.
- Define how the junction will be sealed.
- Confirm material and temperature suitability.
- If open, state the cleaning method and verification.
Avoid inventing a universal number
The cleanable width depends on depth, obstruction, tool, hand access and the component being removed. A copied figure can produce a gap that satisfies a note but fails the real task.
- Measure depth and access angle.
- Use the exact removal envelope.
- Agree the method with the hygiene plan.
What the site evidence may show
| Observation | Hidden issue | Next check |
|---|---|---|
| Gap admits debris | Tool cannot reach full depth | Close or enlarge it |
| Seal applied at front only | Contamination enters from rear | Detail the complete junction |
| Manufacturer gap retained | No cleaning method exists | Coordinate service and hygiene needs |
A practical verification sequence
- Confirm the exact duty and model. Record what the appliance or space must achieve at peak service and use the current model-specific installation information.
- Draw the complete interface. Include moving parts, service/removal access, connections, adjacent equipment and the real operator or trolley position.
- Measure under a representative condition. Static, empty or isolated tests can hide the issue. Record the operating state, value, unit and test point.
- Correct and prove. Repeat the same test after any change and retain the evidence with commissioning or O&M information.
Checks to record:
- Gap width.
- depth.
- obstruction.
- cleaning-tool size.
- panel-removal direction.
- seal material.
- heat movement..
Explain the design choice: hygienically close/seal the junction or create genuinely usable access based on the equipment and cleaning method. The result should be a measurable decision rather than a generic note such as “allow sufficient space” or “services by others”.
Common mistakes to avoid
- Specifying a gap without naming its purpose.
- Sealing only the visible front edge.
- Using combustible or unsuitable infill beside heat.
- Blocking a service or ventilation opening.
Frequently asked questions
What is the minimum cleanable gap?
There is no reliable universal number. It must work for the depth, obstruction, tool and task.
Is zero gap always better?
Only where the junction is hygienically closed and equipment requirements still allow it.
Who should approve the detail?
Coordinate the equipment supplier, fabricator, installer and food-safety requirements before manufacture.
Related Kitchen Install Guide reading
- Where Should Floor Gullies Go in a Commercial Kitchen?
- Electrical Services Through Wet and Hot Kitchen Areas
- What Makes a Stainless-Steel Joint Hygienic?
Record the installation detail before handover
Use the KIG 318 Commercial Kitchen Installation Checklist to record equipment interfaces, measured conditions, outstanding actions and acceptance evidence.
Sources and further guidance
- Regulation (EC) No 852/2004, Annex II
- GOV.UK: Starting a food business
- HSE: University kitchen ergonomic case study
Last reviewed: 14 August 2026. This article provides general commercial-kitchen design and installation information. It does not replace the exact manufacturer instructions, a site-specific design, risk assessment or work by competent specialists. Stop use and obtain competent help where equipment or services may be unsafe.