The Canadian Transportation Agency has had several occasions to consider complaints of persons with allergies who object to conditions encountered while travelling by air. The most well-known and litigated cases involve persons who are allergic to nuts(1) and cats. Most recently, the carriage of pets in the cabin has been the focus of agency jurisprudence. On December 15 2011 the agency released an important decision which confirms that carriers may carry cats as pets in the cabin subject to meeting certain conditions designed to accommodate persons who are allergic to cats. This update reviews the history and details of that case.


The Canada Transportation Act gives the agency responsibility for eliminating, within the Canadian transportation network, undue obstacles to the mobility of persons with disabilities. The agency, with the support of the Supreme Court, has given a very broad definition to 'disability'. Around 10 years ago the agency adopted the language and procedures of the World Health Organisation and its International Classification of Functioning and Disability. Any person with an 'impairment' (broadly defined) coupled with an 'activity limitation' or a 'participation restriction' qualifies as a person with a disability, according to the World Health Organisation. The agency has adopted this approach with some modification. In particular, the agency requires that a complaint demonstrate both an activity limitation and a participation restriction in the context of the transportation network in order to qualify.

In May 2002 the agency applied this approach to a number of complaints of persons with allergies – mainly to cats – and determined that an allergy is an impairment, but that there was no evidence that all persons with allergies will experience limitations and restrictions in the transportation network. Therefore, an allergy is not a disability per se. The agency concluded that it would examine complaints on a case-by-case basis.

In February 2010 the agency considered the complaints of three individuals who presented evidence of an allergy to cats. It continued to accept a very broad definition of 'impairment' and concluded that an allergy is in itself an impairment – irrespective, it seems, of the severity of the sensitivity. However, it did impose some restriction on the class of person that qualifies for accommodation in its discussion of the requirement that there be an activity limitation. This limitation must be "significant enough to result in an inherent difficulty in executing a task or action". Thus, a person whose allergic reaction is "limited to throat and eye irritation and a runny nose" will not qualify. On the other hand, a person will not need to establish that his or her condition is "at the most severe end of the spectrum" in order to be considered a person with a disability.

Applying these principles in 2010, the agency found that three complainants were persons with allergies to cats and that in each case the severity of the allergy was enough to reach the disability threshold. The complainants sought a ban on the carriage of all pets in the cabin and argued that the agency should not limit its consideration to cats. The agency did not agree and concluded that it would limit its consideration to the carriage of cats as pets in the passenger cabin. It then proceeded to determine whether the policies of the carriers involved in the case (Air Canada, Jazz and WestJet) constituted an obstacle to the complainants.


The decision, released in December 2011, marked the conclusion of the examination of the obstacle issue. Over the past few years the agency has developed an increasingly defined and formalised approach to the identification of obstacles. Once a person is found to have a disability, the agency will ask what steps are required to meet the person's needs and provide him or her equal access to the national transportation network. These responsive measures are referred to as 'appropriate accommodation'. If appropriate accommodation is found to exist, the person with a disability has not encountered an obstacle. Therefore, in recent cases the agency has, at the obstacle stage of the inquiry, established what it considers to be appropriate accommodation. The carrier is then given an opportunity to provide that accommodation or, alternatively, to demonstrate that providing the accommodation would impose undue hardship upon it.

In this case, all the complainants sought one primary accommodation – a complete ban on cats in the passenger cabin. In its strictest form, this ban would apply regardless of whether a particular flight included among its passengers a person with an allergy to cats. The agency refused to consider such an extreme measure, but did conclude that a ban on cats in the passenger cabin of an aircraft which included among its passengers a person with an allergy to cats would be an appropriate form of accommodation. However, the agency gave consideration to other steps – including ventilation and filtration of cabin air, which can be taken to minimise exposure to cat dander – and concluded that a ban on cats in the cabin is not the only form of appropriate accommodation.

Air Canada and WestJet introduced evidence that cabin air in all their aircraft is filtered through high-efficiency particulate air (HEPA) filters. These HEPA filters are designed to "eliminate 99.97 percent of contaminants with a particle size of 0.3 microns". Particle size is clearly an important consideration. Although some participants in the proceeding sought to cast doubt on the efficiency of the HEPA filters, the agency concluded that the best evidence on file was to the effect that particles of cat dander are approximately 2.5 microns in size and noted that this is several times larger than the smallest particles that the filters can eliminate. Thus, the use of HEPA filters is an important element in a package of alternate appropriate accommodation.

Two other elements of such a package are air circulation and physical separation of the person with the allergy from the cat. A medical doctor who provided advice to the agency noted that "in aircraft cabins that have 20 to 30 air exchanges per hour, the air ventilation removal rates would be more significant and efficient means of allergen elimination". All aircraft in WestJet and Air Canada fleets provide this level of air exchange.

The carriers involved in the proceeding all had policies in place to ensure the separation of cats carried in the cabin from allergic passengers, but the agency determined that these policies should specify a minimum distance of separation, which they did not at the time.

After considering the alternatives put forward, the agency concluded that there are two basic approaches to appropriate accommodation, either of which would be adequate. A carrier may decide to ban the carriage of pet cats in the cabin of an aircraft in which a person with a significant allergy to cats is travelling, but need not do so if it can provide a set of measures including air filtration and circulation and physical separation to address the problem. The majority decided that the separation should be a minimum of five rows. A single member dissented on this point. In his view, the evidence supported no more than two rows of separation.


In this case, as in the decision dealing with the accommodation of persons with allergies to nuts, the agency has shown sensitivity to the fact that it is impossible to eliminate all allergens from an aircraft cabin and to the unacceptable implications of attempting to exclude from the cabin all substances to which some individual may be allergic.

For further information on this topic please contact Gerard A Chouest at Bersenas Jacobsen Chouest Thomson Blackburn LLP by telephone (+1 416 982 3800), fax (+1 416 982 3801) or email ([email protected]).


(1) For further details please see "Nut allergies and air travel".