The phrase "and as needed" is correct and usable in written English.
It can be used to indicate that something should be done or provided when it is necessary or required.
Example: "Please review the document and make changes as needed."
Alternatives: "and when necessary" or "and if required".
Up to you and as needed to feel comfortable with your mastery of the course material.
In other organizations, you may be responsible for all the servers and, as needed, the workstations.
They have no resident rabbi; an itinerant rabbi visits from Avignon to officiate during holidays and as needed.
We're not counting the cost there and we're staffing that function as appropriate and as needed to ensure that every ad is fully screened.
The program's success ultimately will rest on whether the administration is willing to intensify its efforts and, as needed, shift gears.
A hallmark of China's success has been its leaders' willingness to revise the country's economic model when and as needed, despite opposition from powerful vested interests.
Emeritus faculty members may be assigned office space as available and as needed, although they have lower priority than active members of the faculty and staff.
*The state would sell revenue bonds totaling many billions of dollars to purchase power in long-term contracts and, as needed, on a day to day basis, to make up for the amounts the utilities cannot supply.
The proportion of PIPs among scheduled and as-needed prescriptions were 9.2% and 11.5%, respectively.
We analyzed data with transitional mixed models controlling for personal temperature and humidity, and as-needed β2-agonist inhaler use.
Daily diary responses included asthma symptom severity (6 levels), morning and evening peak expiratory flow rates (PEFR), and as-needed beta-agonist inhaler use.
