NASA-STD-3001 Technical Brief

Relevant Technical 

Requirements

Crew Selection and 

Recertification

OCHMO-TB-034

Rev A

NASA-STD-3001 Volume 1, Rev C

[V1 3001] Selection and Recertification

OCHMO-STD-100.1A, NASA Astronaut 

Medical Standards, Selection and Annual 

Recertification

Executive Summary

Crew Selection and Recertification is 

designed to ensure the health, safety, 

and occupational longevity of NASA 

career astronauts. The standards used 

reflect the medical requirements to 

successfully complete specific mission 

tasks and the multifaceted training and 

performance required. These include, 

but are not limited to, flying in high 

performance aircrafts, extreme 

environment analogs, exposure to 

hypobaric and hyperbaric conditions, 

exposure to unique environments (e.g., 

microgravity), and conducting 

specialized operations (e.g., extravehicular activities, robotic arm 

operations). Health risk assessment is a 

complex and dynamic process, and the 

medical requirements and screening 

procedures take into account the fact 

that the risk for a medical event 

increases with mission duration. Even 

after a thorough astronaut selection 

process, a well-designed medical system 

is still necessary for healthcare issues 

that arise during spaceflight.

2021 NASA Astronaut Candidates

NASA Astronaut selection standards include 

testing for longevity of career, which may be 

reconsidered for non-career astronauts.
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

NASA Astronaut Medical Standards, Selection and Annual Recertification, OCHMO-STD-100.1A

This NASA Technical Standard provides medical requirements and clinical procedures designed to ensure 

crew health, safety, and occupational longevity of NASA career astronauts. It is used for selection and 

annual recertification of astronauts and reflects the medical requirements to successfully complete 

specific mission tasks and the multifaceted training and performance required of an astronaut. NASA 

policy for establishing standards to protect the health and safety of crew and for providing health and 

medical programs for astronauts during all phases of spaceflight is authorized by NPD 1000.3 - The NASA 

Organization, and by NPD 8900.5B - NASA Health and Medical Policy for Human Space Exploration.

The NASA Astronaut Medical Standards, Selection and Annual Recertification applies to all NASA career 

astronaut candidates. The following graphic details the NASA Medical Requirements, Disqualifying 

Criteria, Acceptance Process, and Waiver Process for recertification for NASA Career Astronauts:

2

Background

Medical Requirements

Requirements for Selection and Annual Recertification

Disqualifying Criteria

NASA Review Process

Aerospace Medicine Board (AMB) Chair

Chief Health and Medical Officer (CHMO)

Multilateral Space Medicine Board Chair

Waiver Process (Recertification Only)

Examining Physician

Aerospace Medicine Board Chair

Chief Health and Medical Officer

View the NASA Astronaut Medical Standards, Selection and Annual Recertification document: 

https://www.nasa.gov/organizations/ochmo/aerospace-medical-certification-standard/

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

Candidate astronauts undergo a 

comprehensive medical evaluation as part 

of their selection and annual 

recertification. The medical evaluation 

process includes an extensive medical 

history and physical examination by 

aeromedical physicians and clinical 

specialists, laboratory screening tests, 

special diagnostic tests, and psychiatric 

evaluation. The specific medical evaluation 

procedures used are designed to select 

and certify individuals who are free from 

medical conditions that may: compromise 

the astronaut’s health and safety, 

compromise the completion of mission 

objectives, and be seriously aggravated or 

progress as a result of the performance of 

duties during training (e.g., in the Neutral 

Buoyancy Laboratory [NBL] and U.S. Air 

Force T-38 aircraft) or spaceflight 

exposures.

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Laboratory Testing

Special Assessments and Imaging 

Procedures

Full Aeromedical Physical 

Examination

Comprehensive Medical 

Questionnaire

Selections Overview

Evaluation

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

This may be completed using the NASA Medical Survey or other similar questionnaire(s).

Comprehensive Medical Questionnaire

The following areas are included but not limited to:

• Past medical history and background information

• Psychosocial and Psychiatric history including:

 DWI and drug-related convictions

• Personal habits/lifestyle

• Travel history (past year)

• Medication review, including:

 non-prescription and herbal medications

 food supplements

 vitamins and minerals

• Symptomatic review of all body systems

• Physical activities and sports

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Reference Data

Full Aeromedical Physical Examination

The following areas are included but not limited to:

• Vital signs: height, weight, pulse and blood pressure (recumbent, sitting, & standing), body 

temperature, respiratory rate

• Head and face (nares/nasal mucosa, sinuses, maxillary and frontal), oropharynx

• Ears (external meatus, tympanic membrane, and response to valsalva)

• Eyes (general appearance, extra-ocular movements, pupil reactivity, and ophthalmoscopic 

exam)

• Neck (thyroid, vascular exam, motion)

• Heart and lungs (cardiovascular exam, including cardiac auscultation, carotid and venous 

upstrokes and peripheral pulses)

• Abdomen (auscultation, palpation of major organs and herniations)

• Rectum/anus (to include prostate exam for males, rectal vault and occult blood testing)

• Genitourinary exam (appearance, general exam, and herniations)

• Breast/chest exam

• Pelvic exam (for female candidates)

• Extremities (to include range of motion and general strength assessments on a 1-5 scale)

• Spine (general appearance and mobility) 

• Skin (includes lymphatics and identifying body marks)

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

5

Laboratory Testing

Clinical laboratory studies are performed to establish baseline values and to aid in the detection of any 

progressing disease. They are limited to those tests pertinent to the identification of the presence of, or 

predilection for disease states, that might compromise individual health, mission effectiveness, or 

safety. 

Laboratory Tests on Selection of NASA Astronauts

Hematology/Thrombophilia Screen 

• Complete Blood Count

• Reticulocyte count 

• Screening tests for thrombophilia: Prothrombin time (PT) and partial thromboplastin time (PTT) 

• Hemoglobin evaluation 

Biochemistry

• Liver function

• Total serum protein

• Renal function 

• Endocrine 

• Fasting blood glucose

• Cardiovascular profile

• Calcium, Magnesium, Inorganic Phosphate 

• Ionized calcium 

• Prostate specific antigen (males over age 40) 

• Serum ferritin

Infectious Disease Screen

• Serologic screen for 

 Hepatitis 

 Hepatitis C 

 HIV 

• Tuberculosis (TB) screening

Urinalysis

• Routine (specific gravity, glucose, protein, pH, ketones, blood), microscopic 

• Human chorionic gonadotropin (hCG) (females) (urine)

Special Studies 

• Prolactin 

• Carbohydrate Deficient Transferrin 

• Ethyl glucuronide 

• Tissue transglutaminase (TTG) IgG 

• Tissue transglutaminase(TTG) IgA

Drug Screening (Urine)

• Drug screen in-house for illicit drugs

• Expanded drug screen 

Reference Data

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

6

Ophthalmology Specialist 

Assessment

Otolaryngology/ENT

Dental Exam

Cardiopulmonary

Gastroenterology

Neurology

Behavioral Health Evaluation

Gynecological

Specialist Assessments

Special Assessments and Imaging Procedures 

Specialty examinations are performed to 

further detect and identify any potential 

disorders within a specific area. Throughout the 

selection and subsequent annual examinations, 

emphasis is placed on the early detection of 

latent pathological processes, and suitability for 

spaceflight and the physiological effects of 

reduced-gravity exposure. Tools like ultrasound, 

12-lead electrocardiogram, X-ray, and MRI are 

used to perform some of these specialized 

medical assessments. 

Reference Data

Houston We Have a Podcast:

Be a NASA Astronaut with NASA astronaut 

Kayla Barron and Anne Roemer, astronaut 

selection manager

Ep136: Be a NASA Astronaut | NASA

Example of specialist assessments, refer to

OCHMO-STD-100.1A for additional details.

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Reference Data

Evaluation - Medical Conditions to Consider for Selection and Annual Recertification of NASA 

Astronauts

The standards used reflect the medical requirements to ensure occupational longevity and 

ensure the ability to complete specific mission tasks and the multifaceted training 

and performance required. Table 7, Disqualifying Medical Standards, of OCHMO-STD-100.1A 

details those medical conditions that are medically disqualifying for the selection and retention of 

NASA astronauts, or that may require further testing and evaluation to assess medical suitability. 

Annual medical recertification ensures the individual has not developed any new medical 

conditions that would preclude safe performance of training and/or spaceflight duties or 

participation.

Excerpt from OCMO-STD-100.1A of general medical conditions that may lead to 

disqualification or require additional testing. Refer to OCHMO-STD-100.1A for 

additional details.

7 10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Back-Up

8 10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Major Changes Between Revisions

10/31/2023

Rev A 9

Original  Rev A

• Updated information to be consistent with NASA-STD-3001 

Volume 1 Rev B and Volume 2 Rev C.
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

NASA-STD-3001 Volume 1 Revision B

[V1 3001] Selection and Recertification Crewmembers shall be medically and psychologically selected and 

annually recertified following the guidance in OCHMO-STD-100.1A, NASA Astronaut Medical Standards 

Selection and Annual Recertification.

Referenced Technical Requirements

10

View the current versions of NASA-STD3001 Volume 1 & Volume 2 on the 

OCHMO Standards website

10/31/2023

Rev A
NASA-STD-3001 Technical Brief

OCHMO-TB-034 Crew Selection and Recertification

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Reference List

1. NASA Astronaut Medical Standards Selection and Annual Recertification [OCHMO-STD-100.1A]. 

National Aeronautics and Space Administration (NASA) Office of the Chief Health and Medical Officer. 

(2021). Retrieved from: https://www.nasa.gov/organizations/ochmo/aerospace-medical-certificationstandard/

2. Medical Evaluation Documents Volume B (MEDB) Revision 4.2. (2022). Internal NASA document.

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Rev A