Our HVAC engineer indicated that ASHRAE 55 cannot be met on a healthcare project because it is not applicable for metabolic rates below 1.0.  Isolation room and ICU patients could be sleeping with a metabolic rate of 0.7 or reclining with a metabolic rate of 0.8 so, therefore, it was their assessment that they cannot comply with the credit requirements.  Given this is the healthcare-specific LEED rating system, the presence of patient care spaces should not presumably not preclude compliance (the credit language specifically references patient rooms).  Has anyone else encounter this / how was it addressed?