"Casual basis," when applied to babysitting services, means employment that is irregular or intermittent and that is not performed by an individual whose vocation is babysitting. Casual babysitting services may include the performance of some household work not related to caring for the children, provided that the work is incidental (i.e., does not exceed 20 percent of the total hours worked on the particular babysitting assignment).
Iowa Admin. Code r. 875-219.4
29 CFR 552.5.