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BCC Ruling No.. 98-10-615

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BUILDING CODE COMMISSION DECISION ON B.C.C. Ruling No. 98-10-615

IN THE MATTER OF Subsection 24 (1) of the Building Code Act, 1992.

AND IN THE MATTER OF Articles 7.2.5.5. and 2.6.4.1. of Regulation 61, as amended by O. Reg. 400/91, 158/93, 160/93, 383/94, 20/95 and 395/96 (the "Ontario Building Code").

AND IN THE MATTER OF an application by Mr. Bruce Lasby, Operations Administrator, Thomasfield Homes Ltd., 295 Southgate Drive, Guelph, Ontario vs. Mr. Bruce Poole, Chief Building Official, City of Guelph, to determine whether a combination microwave and exterior vented hood fan installed approximately 355 mm (14 in) above the top of a stove burner complies with Article 9.33.2.1. of the Ontario Building Code in various units at 1550 Gordon Street and Lot 67, Plan 856, Hse #56, Guelph, Ontario.

APPLICANT
Mr. Bruce Lasby, Operations Administration
Thomasfield Homes Ltd.
Guelph, Ontario

RESPONDENT

Mr. Bruce Poole
Chief Building Official
City of Guelph, Ontario

PANEL
Mr. Roy Philippe (Chair)
Mr. Ross Thomson
Mr. Lawrence Glazer

PLACE
Toronto, Ontario

DATE OF HEARING
March 4, 1998

DATE OF RULING
March 4, 1998

APPEARANCES
Mr. Bruce Lasby
Thomasfield Homes Ltd.
Guelph, Ontario
The Applicant

Mr. Bruce Poole
Chief Building Official
City of Guelph, Ontario
The Respondent

RULING

1. The Applicant

Mr. Bruce Lasby, Operations Administrator, Thomasfield Homes Ltd., Guelph, Ontario was issued an order under the Building Code Act, 1992 to rectify the installation of microwave units at certain new residential structures at various sites at 1550 Gordon Street and Lot 67, Plan 856, Hse #56, Guelph, Ontario.

2. Description of Construction

The Applicant has constructed numerous new residential units in the City of Guelph. The construction of the subject units includes complete cabinetry in the kitchens, as well as the installation of certain appliances. The Applicant proposes to install combination microwave oven/hood exhaust units above the stove burners, at a minimum height in accordance with the manufacturers specifications.

The appliances in question are described as standard microwave units with integral exhaust fans and lights mounted on the underside. The exhaust fumes are vented through ducting within the fan hood and are then are expelled to the upper rear of the microwave, at which point they are forced through standard exhaust ducts. The combination microwave/fan appliances project only 25 to 50 mm (1 to 2 in) beyond the face of the cabinetry.

3. Dispute

The issue at dispute between the Applicant and Respondent is whether the installation of the subject microwave units complies with Article 9.33.2.1. of the Ontario Building Code. This provision requires that a vertical clearance of not less than 750 mm (2 ft, 6 in) must be provided above stove ranges. The Applicant is installing the microwave units as per the manufacturers instructions. The City is not prepared to accept the installation of the microwave units at less than 600 mm (24 in).

4. Provisions of the Ontario Building Code

Sentence 9.33.2.1. Vertical Clearance

1. Except as provided in Sentence(2), a vertical clearance of not less than 750 mm (2 ft 6 in) shall be provided above the elements or burners of electric-and gas-fired domestic ranges.

5. Applicant's Position

The Applicant submitted that the combination microwave/hood fan units are being installed properly - in accordance with the manufacturers specifications. In fact, they are installing most of the subject appliances at approximately 475 to 500 mm (19 to 20 in) above the burner, at least 125 mm (5 in) higher than the manufacturers' permissible minimum installation.

In their view, the OBC and Article 9.33.2.1. in particular, refer only to the clearance of the combustible cabinets above the surface of the cooktop. They also note that the local area fire departments do not have standards regulating the clearance between stoves and microwaves. This is because, as the Applicant argues, the issue of clearance between these two appliances is set by the manufacturers who have had the installation configurations tested by accredited testing agencies. (The Applicant provided material from UL and CSA which indicated that the cooktop to microwave height should be done in accordance with the manufacturer's installation instructions.) It is not an area that is covered by government regulation. They do point out, however, that the proposed installation of the combination microwave/hood fan units is approved by Ontario Hydro.

The applicant further argues that installing the microwave units at the location required by the Respondent would dangerous since users would be required to remove hot items from an unsafe height. In the case of children, they would handling hot food above their heads.

6. Chief Building Official's Position

The Respondent submitted that the proposed installation of the subject appliances do not conform to OBC Article 9.33.2.1. In their view, the Code is clear in its requirements; 750 mm (30 in) clearance above a range, or with a metal exhaust fan hood which extends 125 mm (5 in) beyond the face of the cabinetry the clearance can then be reduced to 600 mm (24 in), as per Sentence 9.33.2.1.(2). Under no circumstance does the Code allow a reduction of clearance to less than 600 mm (24 in).

The Respondent indicated that they had contacted the CSA and had inquired about the testing conducted on the microwave to cooktop clearance. They noted that the relevant test had only used full radiant heat to simulate the cooking elements. Testing with flame was not done. This discrepancy, the Respondent believes, is serious enough to ignore the manufacturer's installation specifications and rely upon the additional clearance set out in the OBC.

The Respondent also submitted that discussions with the Guelph Fire Prevention Office revealed that a number of fires have occurred in kitchens due cooking accidents or grease build up and are then propagated by the cabinetry. By locating the microwave closer to the cooktop, they argue that there is an increased chance for cooking accidents (fire ignition and scalding) since inadequate working space would be provided. As well, the closer proximity may cause greater grease build up to occur.

They also note that the pending 1997 version of the OBC has been amended to clarify this provision that a 750 mm (30 in) clearance is required to any building finish unless protection measures are provided. But in no case can the clearance be less than 600 mm (24 in).

Lastly, the Respondent recommends that the subject appliance make application to the Building Materials Evaluations Commission to have the product assessed and possibly tested. Otherwise, they feel that the proposed microwave installation represents a potential reduction of current safety standards which may place occupants and property in these residential units at risk.

7. Commission Ruling

It is the decision of the Building Code Commission that the installation of the combination microwave and exterior vented hood fan with clearances above the top of the stove burner installed in accordance with the manufacturers instructions provides sufficiency of compliance with Article 9.33.2.1. of the Ontario Building Code.

8. Reasons

i. The clearances required in Article 9.33.2.1. of the Building Code are clarified in the 1997 Building Code to be specific to framing, finishes and cabinets.

ii. The certification agencies for electrical hazards require installation instructions including clearances to stove burners.

iii. These products have been available for a period of time.

Dated at Toronto this 4th day in the month of March, in the year 1998 for application number 1998-01.



_________________________________________________________________

Mr. Roy Philippe, Chair





_________________________________________________________________

Mr. Lawrence Glazer





_________________________________________________________________

Mr. Ross Thomson