In this study, the accuracy of a noninvasive hemoglobin sensor(s) will be assessed by comparison to hemoglobin measurements from a laboratory hematology analyzer. Blood samples are collected from healthy volunteers who are enrolled in either a blood draw procedure or a hemodilution procedure wherein blood is repeatedly sampled as the concentration of hemoglobin is reduced in a controlled manner by administering fluids intravenously.

A. Hemodilution Test Procedure

Inclusion Criteria:

• Weight of more than 110 lbs and less than 220 lbs.
• Physical status of ASA I of II
• Able to read and communicate in English
• Has signed written informed consent
• Female, non pregnant. Female subjects will be provided with a pregnancy test free of charge.

Exclusion Criteria

• Age less than 18 yrs and greater than 35 years
• Weight of less than 110 lbs or more than 220 lbs.
• Hemoglobin less than 12 g/dL
• ASA physical status of III. IV, V.
• Pregnant
• Subject has known drug or alcohol abuse
• Subject has skin abnormalities affecting the digits such as psoriasis, eczema, angioma, scar tissue, burn, fungal infection, substantial skin breakdown, nail polish or acrylic nails.
• Subject has experienced a head injury with loss of consciousness within the last year
• Subject has known neurological and psychiatric disorder that interferes with the subjects level of consciousness
• Known or concurrent chronic usage of psychoactive or anticonvulsive drugs within the last 90 days, or any use in the last 7 day (i.e. tricyclic antidepressants, MAO inhibitors, Lithum, neuroleptics, anxiolytics or antipsychotics, except SSRIs).
• Subject has any medical condition which in the judgment of the investigator, renders them inappropriate for participation in this study, such as Reynauds Syndrome.
• Hypertension: Systolic BP >140 mmHg or Diastolic BP > 90 mmHg.
• Baseline heart rate < 50 bpm.
• Inability to tolerate sitting still or minimal movement for up to 90 minutes
• Discretion of investigator

B. Blood Draw Test Procedure

Inclusion Criteria:

-Subjects must understand and consent to be in the study.

Exclusion Criteria

• Subjects less than 18 years of age.
• Subjects who do not understand the study and the risks involved.
• Anyone deemed ineligible by test personnel.