A union argued that an axle box of a truck was a confined space and so entitled workers working in one to a confined space premium under the collective agreement. The employer disagreed. An arbitrator noted that the collective agreement didn’t define “confined space.” But based on the employer’s code of practice for confined space entry, an axle box didn’t qualify as a confined space. Axle boxes didn’t have limited or restricted entry or exit, which may complicate the provision of first aid or rescue efforts. And this factor is significant in determining whether a space was a confined space, concluded the arbitrator [SMS Equipment Inc. v. UNIFOR, Loca1707A,  CanLII 57998 (AB GAA), Oct. 3, 2014].