What is the test for a claim for deliberate indifference to health and safety under the Eighth Amendment?

1. The Eighth Amendment prohibits state actors from acting with deliberate indifference to an inmate's health or safety. See Farmer v. Brennan, 511 U.S. 825 (1994). A claim based on deliberate indifference to health or safety has two elements. First, an inmate must show he was "incarcerated under conditions posing a substantial risk of serious harm." Id. at 834. Second, the inmate must show he was injured as a result of a defendant's "deliberate indifference" to that risk. Id. Under the deliberate indifference standard, plaintiff must demonstrate prison officials knew he faced a substantial risk of serious harm and that they disregarded that risk by failing to take reasonable measures to abate it. Id. at 847.