I finally found the definition of suitable.
9.3.4 Less favourable financial situation A claimant, by accepting the earnings offered by an employer, should not be put in a less favourable financial situation in comparison with the less favourable of; the financial situation they were in while receiving benefits the financial situation they were in during their qualifying period For example, taking into account the claimant's EI benefits including any working while on claim provisions, employment may not be suitable if accepting the employment means that transportation and child care expenses are so high that the claimant would be in a less favourable financial situation than the lesser of what they are receiving on EI, and what they were earning during their qualifying period. Assuming the claimant is normally entitled to $400.00 a week in EI benefits. If the claimant is offered employment earning $300.00 per week, after the working while on claim earnings of $150.00 are deducted, the claimant would receive $250.00 per week in EI benefits. However, if the claimant's transportation and child care expenses exceed $150.00 per week (or one-half of the offered earnings) the claimant could be in a less favourable financial situation by accepting the employment, therefore the employment may not be suitable. By not accepting the employment this claimant could be entitled to $400.00 in EI benefits. By accepting employment with expenses of $125.00 per week, the claimant would net $425.00 (EI benefits of $250 + $300 employment income minus expenses of $125). With net earnings of $425.00, compared to $400.00 if the employment was refused, the claimant is in a more favourable situation by accepting the employment and so the employment remains suitable. However, if there were expenses of $175.00 per week, the claimant would net a total of only $375.00 (EI benefits of $250.00, + $300.00 in employment income minus expenses of $175.00). In this latter circumstance the net income of $375.00 would be less than the $400.00 the claimant could be entitled to by not accepting the employment, thereby putting the claimant in a less favourable financial situation and making the employment possibly unsuitable. The Commission would then have to examine the financial situation the claimant was in during their qualifying period. If the claimant's net weekly earnings in the qualifying period had been $375.00 or less, then offered employment that nets $375.00 or more would remain suitable. However, if the net weekly earnings in the qualifying period were more than $375.00 then the claimant would be in a less favourable situation by accepting employment that netted only $375.00 per week thus this employment would not be considered suitable.
I think this is the hope I was looking for.