As long as your role pays you for being accessible. The rates vary but should be between 10% to 20% of your hourly pay for the hours you're on call. For example, if you make $50/hour normally you should be getting at least $5/hour for being on call. Think of it like being a babysitter. Most times they just sit around and watch TV or do their homework or chat with their boyfriend. But it's the chance of there something going wrong that they're paid for. I hope you're getting paid for being around in case something goes wrong too.