Do not routinely initiate fluid resuscitation when the burn is less than 15% total body surface area (TBSA).

Partial and full thickness burns affecting less than 15% of the TBSA do not require specific directed fluid resuscitation. Patients with burn injuries under 15% can typically meet their requirements with maintenance intravenous fluid infusions or oral fluid intake alone. There may be other associated indications for fluid replacement, however, such as concomitant trauma, dehydration, alcohol intoxication, or other fluid losses.
 

For more information:

Cartotto R. Fluid resuscitation of the thermally injured patient. Clin Plast Surg. 2009;36(4):569-581. PMID: 19793552.

Gillenwater J, Garner W. Acute Fluid Management of Large Burns: Pathophysiology, Monitoring, and Resuscitation. Clin Plast Surg. 2017;44(3):495-503. PMID: 28576238.

Rae L, Fidler P, Gibran N. The Physiologic Basis of Burn Shock and the Need for Aggressive Fluid Resuscitation. Crit Care Clin. 2016;32(4):491-505. PMID: 27600122.

Saffle JR. Fluid Creep and Over-resuscitation. Crit Care Clin. 2016;32(4):587-598. PMID: 27600130.

Saffle JI. The phenomenon of “fluid creep” in acute burn resuscitation. J Burn Care Res. 2007;28(3):382-395. PMID: 17438489.