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Restaurants · Hospitality · HoReCa

Drain flies.
Odour in the kitchen.
Inspection on the way.

A HACCP plan can be perfect on paper — but if Psychoda drain flies are coming up out of the gully behind the line, it will not survive the next inspection. Green Drain™ physically breaks the breeding cycle in the P-trap and keeps sewer odours behind its silicone seal.

HACCP Int. RG-04NSF/ANSI 2No chemicalsNo drain flies30s installation
0
Fly from the drain
0
Fragrance
5 years
Life
30 s
By the drain
Problem & solution

Why a standard P-trap fails in a kitchen.

A professional kitchen has multiple floor drains. The main line uses them all day. Auxiliary drains — pantries, storage-room corridors, employee washrooms — not always.

Without Green Drain™

  • Traps run dry during seasonal closures and the low season.
  • Fruit flies (Drosophila) and drain flies (Psychoda) reproduce in the P-trap biofilm — a cycle of about 7 days.
  • Flies rise from the drain and land on the preparation — a critical control point in the HACCP plan.
  • Sewer gases (H₂S, NH₃) pass through the dry sump and give off a "kitchen smell" that guests can detect.
  • The sanitation inspector requires an active pest control measure in the drains during inspection.

With Green Drain™

  • Mechanical barrier — the fly simply can't get through the silicone barrier.
  • No breeding in the P-trap — water flows through, but there's no standing water for eggs.
  • No chemicals, no pouring of substances — lower risk to staff health and safety.
  • Listed under the HACCP International programme (RG-04) — basis for a drain pest-control measure
  • Resistant to grease, detergents, and kitchen chemicals
Croatian HoReCa context

Seasonality is a structural risk.

Croatian coastal hospitality establishments often operate only seasonally. According to the Croatian Chamber of Trades and Crafts, in September 2024 there were 11,792 registered hospitality and tourism trades — 165 more, or 1.4 %, than a year earlier. Seasonal closures mean dried-up P-traps — and the flies and smells of the first days of opening.

~7 days
Reproduction cycle of the Psychoda fly in the P-trap (entomological data)
2–4 weeks
Time in which an unused trap runs dry
HACCP International
Listed under RG-04 — basis for a pest-control measure
EC 852/2004
Food Hygiene Regulation — the HACCP obligation for all HoReCa
Codex
Codex Alimentarius — the international HACCP framework
0
No maintenance chemicals — for about five years
Data Sources and Regulatory Framework (2024–2025 data)

Statistical data were taken from official sources: State Statistical Office (data.dzs.hr) Croatian Institute of Public Health (hzjz.hr), Ministry of Labor, Pension System, Family and Social Policy (mrosp.gov.hr), Agency for Science and Higher Education (azvo.hr), Ministry of Tourism and Sports (mint.gov.hr). Regulatory framework: EUR-Lex for EU directives and regulations — Regulation (EU) 2017/745 (MDR), Regulation (EC) No 178/2002 (general principles of food law), Regulation (EC) No 852/2004 (food hygiene — HACCP obligation), Regulation (EC) No 1935/2004 and Regulation (EU) No 10/2011 (food contact materials), Regulation (EU) No 528/2012 (BPR), Directive 2014/34/EU (ATEX). Standards: EN 1253-1 (floor P-traps, water seal ≥50 mm), EN 1253 Parts 6/7/8 (gullies with a water seal below 50 mm, with mechanical closure, and combined types; 2023 editions), ASSE 1072-2020 (floor drain trap seal protection devices) and NSF/ANSI 2 (food equipment). HACCP International RG-04 is a private certification programme operated by HACCP International, not an official certification issued by a public authority. Tourism data taken from the DZS publication for H1 2025, healthcare data from the HZJZ report 2024, data for education from DZS publications for the 2023/2024 and 2024/2025 school years, data for nursing homes from the MROSP report, and announcements of EU-funded construction in 2025. Revision date: May 2026.

Implementation

From audit to opening day in seven days.

Ideal timing — March/April, before the kitchen is serviced for the season. Installation is part of the standard wet cleaning.

01

Mapping

We map every drain by zone: line, prep, stores and washrooms.

02

Sizes

We measure the internal diameter of the grate. Most kitchen gullies take a GD 3 or a GD 4.

03

7-day test

We fit four samples before the season and the head chef judges the result.

04

The whole kitchen

Pre-season wet cleaning — same-day installation.

Model Recommendation

Recommended sizes by area of the restaurant.

A professional kitchen in Croatia operates according to EN 1253 and HACCP standards. Most Croatian hospitality establishments built in the last 20 years have 3″ (75–85 mm) traps in the lines and 4″ (102–110 mm) traps in the central drains under the dishwashing shelves. Older establishments (canteen-type) often have 55–65 mm.

Green Drain™ Recommended for your industry.

  • Line (griddle, fryer, garde manger, plancha)GD 3Standard 3″ size in new construction, critical CCP for flies.
  • Main bay under the sink (3-bay sink area)GD 4Highest throughput, grease-resistant and CIP-compatible.
  • Guest and staff washroomsGD 2 + GD Uri-Tabs™ in the urinal block
  • Exterior terrace with drainage (Adriatic facilities)GD 3Keeps insects out, keeps odours behind the seal.
💬 Not sure of the exact size? Send us a photo of your sink drain — our technical team will respond with a written recommendation within the same business day, free of charge.
Check out Green Drain™ → Request a quote
GD 2
50–58 mm · guest/staff sanitary fixtures
GD 2.5
55–65 mm · older buildings, bar
GD 3
75–85 mm · line, preparation
GD 3–3.5
80–89 mm · traditional P-traps
GD 4
102–110 mm · main channels
GD 5
120–135 mm · stewarding
Questions

What we get asked most.

Will the sanitation inspector accept this as a CCP measure?

Green Drain™ is listed under the HACCP International programme as RG-04, an equipment category suitable for controlling pests and odours from drains. This is a private certification scheme, not an approval issued by a public authority; whether to include the measure in a HACCP plan remains the operator's decision. We will send the technical documentation and SDS in advance for your HACCP file.

What if the grate comes off for cleaning?

The seal stays in the drain — the grate lifts off above it. At the annual service the seal can be lifted out, rinsed and dropped back in.

Will this stop the water at high flow?

No. GD 3 leaks over 105 L/min, GD 4 over 340 L/min — more than the kitchen line can deliver at once.

Complete solution

Three products.
One protection portfolio.

Green Drain™ doesn't work alone — for maximum drain control it's combined with GD Uri-Tabs™ (urinals) and GreenSwirl™ (drain unblocking).

Ready for Free audit?

We come to the site, map the drains, and provide a written recommendation — no cost, no obligation.