Model no s AVI1832, AVI2440, AVI3240, AVI3255, AVI3270, AVI3855, AVI3870

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1 Attention: The Certifier Ref: Certification Letter.docx Date: 9 December 2011 Re: Certification of AVI Pizza Oven Hood Model no s AVI1832, AVI2440, AVI3240, AVI3255, AVI3270, AVI3855, AVI3870 To whom it may concern, As per the requirements of the Building Code of Australia Clause A2.2, I hereby certify as a Chartered Professional Engineer of the Institute of Australia (Mechanical College):- 1) That the eyebrow hoods discussed in this certification comply with the relevant Australian Standards listed in the Building Code of Australia. 2) That the certification method complies with Clause A2.2 3) That the ventilation systems described with the model no s AVI1832, AVI2440, AVI3240, AVI3255, AVI3270, AVI3855, AVI3870 are capable of equivalent performance to that required by the Building Code of Australia and it s relevant referenced standard - Australian Standard AS ) That the same ventilation systems comply with the requirements of the Building Code of Australia, Section F (Health & Amenity). The basis of this certification is as follows:- no alterations to the manufacturer plans portrayed on the WOLFE Certification Drawings 1,2 & 3 without experienced engineering input maintenance of the system components in line with the manufacturer s advice no increases to the equipment heat output in the oven model that aligns with the hood model Attached to this certificate is:- a. the current definition of Evidence of Suitability at the time of provision b. Further Discussion, which highlights the calculation methodology, and the calculation results for the derivation of air quantities. c. Further Discussion which highlights compliance with all of the components of the referenced Australian Standard AS d. Required Maintenance activities on which the certification is based. The motivation for not using a conventional kitchen extraction hood includes:- 1. Greater safety surrounding better containment 2. More efficient ventilation service provision Yours sincerely For and on behalf of SEED Rob Lord MIEAust CPEng Director of SEED Chartered Professional Engineer (Institute of Engineers Australia) Mechanical Licence number: rob@seedengr.com ph: ) The use of mechanical ventilation & air conditioning in buildings Mechanical Ventilation for acceptable indoor-air quality. Registered office 24 Ellesmere Street Yeronga ABN

2 Relevant Components of the Building Code of Australia Volume 1 Clause A2.2 Evidence of suitability The following excerpt is provided from within the BCA Volume 1. The components relevant to this certificate are highlighted in BOLD below:- (a) Subject to A2.3 and A2.4, evidence to support that the use of a material, form of construction or design meets a Performance Requirement or a Deemed-to-Satisfy Provision may be in the form of one or a combination of the following: (i) A report issued by a Registered Testing Authority, showing that the material or form of construction has been submitted to the tests listed in the report, and setting out the results of those tests and any other relevant information that demonstrates its suitability for use in the building. (ii) A current Certificate of Conformity or a current Certificate of Accreditation. (iii) A certificate from a professional engineer or other appropriately qualified person which (A) certifies that a material, design, or form of construction complies with the requirements of the BCA; and (B) sets out the basis on which it is given and the extent to which relevant specifications, rules, codes of practice or other publications have been relied upon. (iv) A current certificate issued by a product certification body that has been accredited by the Joint Accreditation System of Australia and New Zealand (JAS-ANZ). (v) * * * * * (vi) Any other form of documentary evidence that correctly describes the properties and performance of the material, (b) Evidence to support that a calculation method complies with an ABCB protocol may be in the form of one or a combination of the following: (i) A certificate from a professional engineer or other appropriately qualified person which (A) certifies that the calculation method complies with a relevant ABCB protocol; and (B) sets out the basis on which it is given and the extent to which relevant specifications, rules, codes of practice and other publications have been relied upon. (ii) Any other form of documentary evidence that correctly describes how the calculation method complies with a relevant ABCB protocol. Page 2 of 12

3 Further Discussion Certification for AVI Pizza Oven Hood What is the ventilation principle behind the AVI Pizza Oven Eyebrow Hood? The prime function of any kitchen canopy is to protect the area surrounding the cooking process from soiled matter and flame to make tolerable and safe the immediate area for people to work in. An air flow is created across the cooking process to capture the fumes created, and the by-products of this vapour shall be collected and contained by means of the filters within the canopy, allowing the cleaner air to be discharged. This is containment. Conveyor pizza ovens allow for the rapid cooking of food products with consistency and ease of operator use. They generally have a large kitchen footprint, a high-input gas burner or electric elements, and a high volume capacity to cook the food at a very high rate. The importance of considering the required ventilation rate as well as the energy input and efficiency for such a powerful appliance cannot be understated. The eye brow hood is also sometimes identified as the pants leg exhaust system. The image below portrays the concept. The entry and exit of the cooking process are each managed by an eyebrow ventilation system and the space in between the two eye brows is provided with an even heat that prevents condensation on any surfaces. Ventilation efficiency is significantly increased with the eyebrow concept as the air quantities required for successful containment are proportional to the area of the eyebrow entry. The eyebrow hood certified in this document has specific features to minimise the eye brow entry area and hence it is capable of significant reduction of exhaust air quantities compared to conventional extraction systems. Page 3 of 12

4 What is the Audit Trail from the Building Code of Australia to the permissible use of this product? The flow chart below is Figure 1.1 General Application of this Standard from AS It establishes that Section 5 and in particular Figure 5.1 is the correct procedure for this application. Page 4 of 12

5 Figure 5.1 of Section 5 allows Local exhaust to be used in lieu for part or all of the general exhaust. It identifies Clause as the legitimate clause for approval and also requires the designer to comply with other elements such as satisfactory discharge of exhaust. Page 5 of 12

6 The clause lists the 5 conditions (a-e) for approval and it is re-presented below:- Page 6 of 12

7 What are the conditions for approval (supplier certification only) and how are they met? Conditions for Approval Effluent shall be collected as close as practicable to the source using special surroundings How are they met? The eyebrow hood style permits the complete surrounding of the cooking process with only the smallest gaps to permit air entry. Local exhaust rates shall be in accordance with relevant Australian Standards or the American Conference of Governmental Industrial Hygienists Industrial Ventilation manual The Australian Standard AS deliberately does not address the airflow rates for local exhaust systems. However, the British Specification for Kitchen Ventilation (HVCA DW/172) does provide for the thermic method and also identifies the use of eyebrow hoods for Conveyor Pizza Ovens. Using the largest oven model XLT , it is derived that an airflow of 420L/s will be required for a 3 bay pizza oven. Certain applicatiosn may require a further 15% increase that is, 483L/s. The exhaust rates specified by the AVI eyebrow hood are 566L/s (i.e. 1200cfm). This airflow rate is the result of Schlieren visualization testing and no reduction in airflows below 566L/s is covered by this certification. Registered office 24 Ellesmere Street Yeronga ABN

8 Conditions for Approval How are they met? The airflow rates from DW/172 is portrayed below. Note that these rates are calculated as per lineal meter :- Local exhaust may be a substitute for general exhaust where the resultant contamination level is equal or less that of general exhaust The schlieren visualization conducted by the Food Service Technology Centre (July 2009) shows no breach of fumes at 1200cfm (566L/s) and hence, it is permissible that this eyebrow hood can replace general exhaust systems. The decision to ventilate the remainder of the kitchen is undertaken by the mechanical designer for the site s installation and is not covered by this certification. Page 8 of 12

9 Conditions for Approval Make-up air openings shall be positioned so as to not be detrimental to capture How are they met? The image below portrays that the hood has clearly defined air intake points. The clearances specified for maintenance (approximately 500mm is nominated in manufacturer s documentation) will permit sufficient air entry without excessive turbulence. Sufficient airflow shall be distributed evenly across the hood The filters within the hood create a self-balancing airflow pattern that stretches across the width of the pizza oven. This criterion is achieved. Page 9 of 12

10 In addition, AS also requires construction related compliance:- Compliance to the kitchen hood references in AS (Appendix C) are valid for the following items:- construction-related items maintenance related items distances between heat sources and grease arresting devices (Continued on the following page) Registered office 24 Ellesmere Street Yeronga ABN

11 Visual inspection of the hoods and review of the workshop drawings confirms construction related compliance with Appendix C:- Compliance with C3.1 is evident. There is a very short stretch of horizontal face adjacent the filter faces but no signs of condensation. This is permissible as Appendix C describes internal surfaces as sloping at 40 0 to the vertical unless the design & performance of hoods prevent the formation of any condensate on such surfaces. Compliance with C3.2 is self-evident. Compliance with C3.3 is evident with the use of the collar or plenum above the hood. Compliance with C3.4.1 is self-evident. As mentioned previously, there is a very short stretch of horizontal face adjacent the filter faces but no signs of condensation. This is permissible as Appendix C describes internal surfaces as sloping at 40 0 to the vertical unless the design & performance of hoods prevent the formation of any condensate on such surfaces. Compliance with C3.4.2 & C3.4.3 is self-evident. Note there are no hood gutters as such there are drains under the filters that are sized to drain captured grease into the removable grease containers. Compliance with C3.4.4 has been demonstrated both on site and with Schlieren visualization testing and thus is self-evident. Compliance with C3.4.5 is self evident. Access is from behind the vapour seal. Page 11 of 12

12 Maintenance & Cleaning Certification for AVI Pizza Oven Hood The following table is provided by the manufacturer s installation manual and this list of activities is the basis of this certification. Note that fire suppression [where installed] will also require maintenance and inspection. Page 12 of 12