Can a prison officer be held liable for negligence or gross negligence for failing to provide medical staff with medical equipment?

825, 834 (1994). A showing of negligence or gross negligence is not sufficient. Id. at 835-36; Wood v. Housewright, 900 F.2d 1332, 1334 (9th Cir. 1990). Rather, a prisoner must show that the defendant acted with "deliberate indifference" to his health or safety. Farmer, 511 U.S. at 834. To do so, the prisoner must establish that the defendant knew of and disregarded an excessive risk to his health or safety. Id. at 837, 842 (knowledge can be inferred from the obviousness of the risk). A prison official may thus be free from liability if he or she did not know of the risk or took reasonable action in response to the risk. Id. at 844.