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24 hours a dayu is the most popular phrase on the web.

24 hours per day 13,060,000 results on the web	24 hours a dayu 168,400,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
2.3. the transport must be authorised by the competent authorities, who must be contactable 24 hours per day, 7 days per week, is designed to be operational 24 hours per day and 7 days per week; Hence, many are 'on call' 24 hours per day, 7 days a week, 52 weeks of the year, with little or no opportunity to enter paid employment or to enjoy a normal social life. the emergency must be documented by the veterinary surgeon on call 24 hours per day, 7 days per week; Ability to work 24 hours per day on more than one site for 10 days. Ability to work on one site 24 hours per day for 7 days. 2.1. the emergency must be documented by a veterinary surgeon, on call 24 hours per day, 7 days per week, the transport operation must be authorised by the competent authorities who must be reachable 24 hours per day, 7 days per week;	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

24 hours per day

13,060,000 results on the web

24 hours a dayu

168,400,000 results on the web

More popular!

2.3. the transport must be authorised by the competent authorities, who must be contactable 24 hours per day, 7 days per week,
is designed to be operational 24 hours per day and 7 days per week;
Hence, many are 'on call' 24 hours per day, 7 days a week, 52 weeks of the year, with little or no opportunity to enter paid employment or to enjoy a normal social life.
the emergency must be documented by the veterinary surgeon on call 24 hours per day, 7 days per week;
Ability to work 24 hours per day on more than one site for 10 days.
Ability to work on one site 24 hours per day for 7 days.
2.1. the emergency must be documented by a veterinary surgeon, on call 24 hours per day, 7 days per week,
the transport operation must be authorised by the competent authorities who must be reachable 24 hours per day, 7 days per week;

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.