EHEDG hygienic design training

International (Europe-based) · European Hygienic Engineering & Design Group · professional · unverified source

37practice questions written to this syllabus
4subjects

Format

Unverified. Hygienic design courses and certificates for engineers and food technologists.

Over the years

Unverified: only the home page was confirmed. The guidelines themselves are cited in the food-plant-design-utilities subject.

Official source: https://www.ehedg.org/

Subjects this exam draws on

Transport Phenomena in Food Processing: Fluid Flow, Heat & Mass Transfer3 questionsMechanical Unit Operations: Size Reduction, Mixing & Separation2 questionsFood Plant Design, Hygienic Engineering, Utilities & Automation20 questionsFood Plant Sanitation, Cleaning & Pest Management12 questions

Five practice questions, worked

Original questions written to this exam's published syllabus and pattern. Not past papers.

1. Orifice plates are seldom used to meter milk in hygienic process lines mainly because they

  1. cannot measure any liquid denser than water at room temperature
  2. work only at flows below 1 L/h
  3. measure temperature, not flow
  4. are hard to clean and cause permanent pressure loss
Answer and working

D. are hard to clean and cause permanent pressure loss

Orifices create crevices and dead zones and large permanent losses; magnetic and Coriolis meters are preferred for hygienic duty.

Transport Phenomena in Food Processing: Fluid Flow, Heat & Mass Transfer · Fluid statics and the Bernoulli equation

2. Hygienic design of food conveyors requires

  1. porous wooden surfaces to absorb moisture
  2. smooth, crevice-free surfaces that are easy to clean
  3. hidden lubrication points above the product
  4. fixed guards that cannot be removed for cleaning or inspection by the crew
Answer and working

B. smooth, crevice-free surfaces that are easy to clean

Smooth, non-absorbent surfaces, no harbourage points and easy dismantling or CIP are required; lubricants must not contaminate product.

Mechanical Unit Operations: Size Reduction, Mixing & Separation · Material handling: conveyors and elevators for foods

3. In a ready-meal plant, where is the boundary between low-risk and high-risk areas ideally placed?

  1. At the goods-inwards dock, because raw materials are the only source of contamination in the plant
  2. At the canteen entrance, so that staff change clothing only at meal breaks and not between rooms
  3. At the lethal step itself, such as a through-wall oven loaded on the raw side and emptied on the cooked side
  4. At the dispatch door, so that all production rooms share one zone and staff can move freely inside it
Answer and working

C. At the lethal step itself, such as a through-wall oven loaded on the raw side and emptied on the cooked side

The best barrier is the cooking equipment: raw product enters on the low-risk side and cooked product leaves on the high-risk side, so nothing crosses the wall uncooked. A single shared zone or a boundary at the canteen or dock leaves cooked product exposed to raw-side contamination.

Food Plant Design, Hygienic Engineering, Utilities & Automation · Plant layout: product, process and hygienic zoning

4. Why are low-foaming non-ionic surfactants chosen for CIP detergents?

  1. Foam causes pump cavitation and poor contact in closed circuits
  2. Non-ionic surfactants are the only ones that saponify fat
  3. Foam makes the detergent more alkaline and corrosive
  4. Foam is needed only for sanitising, not for cleaning
Answer and working

A. Foam causes pump cavitation and poor contact in closed circuits

In circulated systems foam entrains air, causes pump cavitation and loss of flow and can prevent liquid contacting surfaces. Foaming is wanted only in open foam cleaning. Non-ionics do not saponify; alkali does.

Food Plant Sanitation, Cleaning & Pest Management · Detergents: chemistry and selection

5. An open conveyor frame is being specified. Which construction meets hygienic design principles?

  1. Box sections and angle iron welded into a closed frame that keeps water out of the interior
  2. Open frame of round tubes, minimal horizontal surfaces and floor clearance for cleaning beneath
  3. A frame sitting flush on the floor so that nothing can get underneath it during production
  4. Flat horizontal shelves under the belt to collect fallen product for later recovery
Answer and working

B. Open frame of round tubes, minimal horizontal surfaces and floor clearance for cleaning beneath

Round tubes shed water and soil, open frames can be seen and cleaned, and clearance from the floor allows cleaning beneath. Hollow box sections and angle iron trap soil and are hard to inspect, horizontal ledges collect debris, and frames flush to the floor create inaccessible crevices.

Food Plant Design, Hygienic Engineering, Utilities & Automation · Hygienic design of equipment: EHEDG and 3-A principles

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