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BCC Ruling No. 00-07-739

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

AND IN THE MATTER OF Sentence of Regulation 403, as amended by O. Reg. 22/98, 102/98, 122/98, 152/99, 278/99, 593/99 and 597/99 (the "Ontario Building Code").

AND IN THE MATTER OF an application by Mr. Mike Godawa, Principal, Keen Engineering Co. Ltd., Toronto, Ontario, for the resolution of a dispute with Mr. Bruce Poole, Chief Building Official, City of Guelph, Ontario, to determine whether the as-constructed acid vents serving plumbing fixtures of more than one laboratory room comply with Sentence of the Ontario Building Code at the Southern Crop Protection and Food Research Centre, 93/95 Stone Road West, Guelph, Ontario.

Mr. Mike Godawa, Principal
Keen Engineering Co. Ltd.
Toronto, Ontario

Mr. Bruce Poole
Chief Building Official
City of Guelph

Mr. Kenneth Peaker (Chair-Designate)
Mr. James Lischkoff
Mr. Fred Barkhouse

Toronto, Ontario

February 17, 2000

February 17, 2000

Mr. Paul Dowsett, Partner
Scott Morris Architects
Toronto, Ontario
Agent for the Applicant

Mr. Rob Reynen
Supervisor of Inspection Services
City of Guelph
Designate for the Respondent


  1. The Applicant

Mr. Mike Godawa, Principal, Keen Engineering Co. Ltd., Toronto, Ontario, has received an order to comply under the Building Code Act, 1992, to remedy certain alleged deficiencies at the Southern Crop Protection and Food Research Centre, 93/95 Stone Road West, Guelph, Ontario.

  1. Description of Constrution

The Applicant has recently completed a partial renovation of, and construction of a new addition onto, an existing building known as the Southern Crop Protection and Food Research Centre. The addition is described as one storey in building height, approximately 9,796 m2 in building area and is classified as a Group F, Division 2 occupancy. The building is of noncombustible construction and is equipped with a sprinkler system and a fire alarm system, but not a standpipe and hose system.

The addition is intended as a research facility and has been designed to contain ten separate laboratory areas. Each laboratory is equipped with several plumbing fixtures. The entire new addition is leased by a single tenant, Agriculture and Agri-Food Canada. All laboratories are supervised by a single director of operations.

The construction in dispute involves the as-constructed acid waste vent system. This system, which is entirely separate from the sanitary drainage venting, has been designed and installed so that the ten laboratories are served by a venting network that terminates in four openings to the exterior. Thus, the four connections to the open air in the as-built acid waste vent system each serve multiple plumbing fixtures in multiple laboratory rooms.

  1. Dispute

The issue at dispute between the Applicant and Respondent is whether the as-constructed acid vents serving plumbing fixtures of more than one laboratory room comply with Sentence of the OBC. According to this provision, vent piping serving a corrosive waste drainage system or dilution tank must extend separately to the open air. At issue is whether Sentence simply requires that the vents serving a corrosive waste drainage system be separate from the sanitary drainage venting, as is the case in the Southern Crop Protection and Food Research Centre, or whether each vent serving an acid waste plumbing fixture must extend independently of other such vents to the exterior.

  1. Provision of the Building Code

Sentence - Venting of Corrosive Drain Piping and Dilution Tanks

    1. Vents connecting to the corrosive drain piping or dilution tank shall extend independently to and terminate in open air.

  1. Applicant's Position

The Agent for the Applicant submitted that his interpretation of Sentence is that it only requires that the acid waste venting system be separate from that of the sanitary drainage vents. He argued that the intent of this Code provision is to prevent corrosive fumes from entering the sanitary plumbing venting system, thereby eliminating a potentially hazardous mix of gases. In his opinion, this Sentence does not, in any way, require that each and every plumbing fixture designed to handle corrosive substances is to be separately vented to the exterior from all other like vents. In fact, he argued that since the Code is silent on how many acid waste vents are required to extend to the exterior, it would be permissible to interconnect all corrosive plumbing fixtures to one single vent terminating in the open air.

To support his position, the Agent referenced a letter he received from the National Research Council's Canadian Codes Centre in Ottawa stating the intent of National Plumbing Code provision 5.5.3.(1), which is identical to OBC It states that "to prevent corrosive fumes from entering the sanitary venting system, vents serving corrosive drains, should be independent of sanitary venting system." It does not make any mention of extending the individual acid vents to the exterior, he noted. The Agent also quoted from a letter submitted to the Applicant by Peter Hughes, a Principal at Keen Engineering, the mechanical engineers for the project, which he indicated articulated their position well. Referring to the wording in Sentence the letter states:

"This means that acid vents, the word "vents" is plural not singular connected to drain piping (the word "piping" is plural not singular) indicates the entire system independent from the regular sanitary vent system [original emphasis] not each fixture vent shall terminate to open air.

"There is no way or has it ever to my knowledge meant taking each and every single vent from each and every fixture separately piped to atmosphere, just think about how ridiculous this would be if you had a multi-storeyed building with hundreds of fixtures, there would be a maze of vertical vent pipes looking like a salt shaker top building with the hundreds of vent pipes sticking through the roof [sic].

"If any building in North America has a [sic] acid waste vent system installed this way then the Engineers and building officials in my opinion would likely be open to legal action due to the additional costs that they have placed on the owner without justification or code requirements.

"An example of how wrong it is to interpret the code the way you have mentioned is as follows:

"If each fixture vent must be separate to the roof and atmosphere then why would not each fixture waste not be separate to the acid neutralizer chamber.

"I have been designing plumbing systems for over thirty years and have sat in so many plumbing code committees and plumbing task forces, never have I heard of such a [sic] interpretation.

"In conclusion the wording in the code is similar wording used in most North American codes and is meant to tell the designers that acid vent systems must be independently piped up to atmosphere and not connected to the regular sanitary vent system, that's all the wording means. Perhaps it's not a well-worded clause but there is no other meaning intended."

The Agent then focussed his arguments on the safety of the as-built acid venting system in the Southern Crop Protection and Food Research Centre. He argued the system is very safe primarily because the separation between the sanitary and corrosive plumbing venting systems, as required in Sentence, has been achieved. The dilution tank is also separately vented. As a result, no volatile mixture of gases will occur between these systems.

Furthermore, he noted that in accordance with the Industrial Health and Safety Act there was a single director responsible for the entire facility, its staff and laboratory activities. The director's responsibilities include purchasing of all substances, monitoring the use of chemicals during experiments and disposal of waste products, including discharge into the plumbing fixtures. The Agent submitted a letter from this director indicating that due to the nature of the experiments conducted in the labs, the materials discharged into the corrosive fixtures will be compatible in vapour and liquid form and will thereby not create a hazardous condition. Thus, the Agent concluded by stating that the interconnecting of corrosive vents serving these subject labs will provide perfectly safe venting.

  1. Respondent's Position

The Respondent submitted that Sentence of the OBC could be read that each trap serving every fixture requires separate and individual venting to exterior. However, as a Code provision, the Sentence, he noted, lacks clarity. As he explained, since Sentence was introduced into the OBC in its 1997 version, he and his colleagues have had some doubt as to its intent, specifically how it is to be applied. In an effort to gain an understanding of this issue, the building department obtained a verbal interpretation from the Ontario Plumbing Inspectors Association in 1998. The interpretation of that body was that "each trap serving a fixture, which handles corrosive waste, was to be individually vented to the open air."

The Respondent also indicated that previous correspondence with the technical staff in the Ministry's Housing Development and Buildings Branch supported a similar view in that all fixture traps in a single lab may, under the right conditions, be safely interconnected. Moreover, any interconnection between separate labs depends on good design, good engineering practice and appropriate supervised use.

For these reasons, and because of past experience with other labs, the municipality took the position that they were prepared to accept that all the fixtures in a single lab could be collectively vented. However, interconnecting venting among different labs creates a hazardous situation due to the fact that scientists in different rooms will have little idea what is being poured into a sink in another lab. The municipality, the Respondent noted, does not have the authority nor the staff and expertise to control what chemicals are used and how they are mixed. In fact, they have no control over the operation of the building. Their responsibility ends with occupancy. And if a lab were to be leased to another similar tenant there would be no change of use triggered. Because of this, the Respondent argued that he would prefer to see a passive life safety system built under the OBC, i.e. adequate venting to the exterior, that does not rely on regulating the behaviour of individuals now and into the future.

  1. Commission Ruling

It is the decision of the Building Code Commission that the acid vents serving plumbing fixtures of more than one laboratory room complies with Sentence of the Ontario Building Code at the Guelph Food Research Project, 93/95 Stone Road West, Guelph, Ontario, provided:

a) That no hazardous chemical interaction occurs in the subject corrosive waste venting system.

  1. Reasons

a) It is our interpretation that Sentence of the Ontario Building Code does not require each trap serving a plumbing fixture capable of handling corrosive waste to be separately and individually vented to the exterior. It simply requires that the acid waste venting system be separate from that of the sanitary venting and that it extend to the exterior.

b) The Code is silent regarding the number of exterior termination points required of an acid waste venting system.

Dated at Toronto this 17th day in the month of February, in the year 2000, for application number 1999-90.


Mr. Kenneth Peaker, Chair-Designate


Mr. James Lischkoff


Mr. Fred Barkhouse