Subject: Date: INFORMATION: Guidance for Medical Screening of March 31, 2003 

Commercial Aerospace Passengers 

Reply to 

From: Attn. of: Federal Air Surgeon, AAM-1 

Director, Civil Aerospace Medical Institute, AAM-3 

To: Associate Administrator for Commercial Space 

Transportation, AST-1 

This document provides general guidance for operators of manned commercial 

aerospace flights (suborbital and orbital) in the medical assessment of prospective 

passengers. 

This guidance is designed to identify those individuals who have medical 

conditions that may result in an inflight medical emergency or inflight death, or may 

compromise in any other way the health and safety of any occupants (crew 

members and passengers) onboard a commercial aerospace vehicle. Space flight 

exposes individuals to an environment that is far more hazardous than what is 

experienced by passengers who fly onboard current airline transports. With orbital 

and suborbital flights, pre-existing medical conditions can be aggravated or 

exacerbated by exposure to environmental and operational stressors such as 

acceleration, microgravity, and solar/cosmic radiation, among others. 

In view of the wide variety of possible approaches that can be used to design and 

operate manned commercial aerospace vehicles in the foreseeable future, the 

medical screening guidance described in this document apply differently to two 

categories of passengers: 

1) Passengers Participating in Suborbital Aerospace Flights (or exposed to a Gload of up to +3Gz during any phase of the flight). These passengers should 

complete a simple medical history questionnaire (enclosed) prior to every 

suborbital flight (single or multiple). A physician who is experienced or trained 

in the concepts of aerospace medicine should review the completed 

questionnaire. These passengers need not be required to undergo a 

physical examination or complete medical laboratory testing. However, 

nothing in this guidance should preclude the physical examination of any 

prospective aerospace passenger as deemed necessary by the physician 

who is authorized by a commercial aerospace vehicle operator to conduct 

medical assessments. Also, if the possibility exists that the G-load profile of 
any suborbital flight could exceed +3Gz, the passenger should be evaluated 

according to the recommendations for passengers participating in orbital 

aerospace flights. 

2) Passengers Participating in Orbital Aerospace Flights (or exposed to a G-load 

exceeding +3Gz during any phase of the flight). These passengers should 

complete a more comprehensive medical history questionnaire and undergo a 

physical examination with laboratory testing. This recommendation applies to 

passengers involved in orbital flights of any duration (short or long) or in 

suborbital flights with high G-load profiles. The medical history, physical 

examination, and medical tests should be valid for a period of one (1) year. 

However, one to two weeks prior to each flight it is recommended that 

passengers should have their medical history updated and undergo an 

abbreviated physical examination to ensure that no significant medical 

changes have occurred since the completion of the initial medical screening 

examination. 

This medical screening guidance is based on the assumption of an inflight cabin 

environment with a barometric pressure not exceeding 8,000 ft (10.91 psi), where 

passengers are not required to wear a pressurized suit. In addition, passengers 

are expected to be able to perform an emergency evacuation without assistance, 

and not compromise the safety of other occupants (crew members and 

passengers). 

For passengers who fly onboard an aerospace vehicle that accelerates faster than 

+3Gz, assumptions are made that such a vehicle will not exceed a maximum 

acceleration load (G-load) of +4Gz (gradual onset) during any phase of the flight 

and passengers will not be required to use an anti-G suit. In general, the 

acceleration envelope recommended for the aerospace vehicle should not exceed 

+4Gz (-2Gz), ±4Gx and ±1Gy The main risks for problems with acceleration in 

aerospace flight are associated with the neurological, cardiovascular, and 

musculoskeletal systems. To avoid the potential for compromising neurological 

function, acceleration forces are preferably applied in the front-to-back (+Gx) 

direction (eyeballs in). An individual is very tolerant to +Gx acceleration, and with 

the heart and brain located at approximately the same level within the acceleration 

field there is little risk for acceleration (G)-induced loss of consciousness (G-LOC). 

Acceleration stress is known to be dysrhythmogenic (changes in cardiac rate, 

rhythm, and conduction). Higher and longer exposures to acceleration increase the 

frequency of dysrhythmias. As long as the head, neck and spine are stabilized 

before the acceleration exposure and remain so until the exposure is completed, 

the potential for musculoskeletal injury is markedly reduced. An individual’s 

tolerance to head-to-foot (eyeballs down) acceleration (+Gz) is dependent on the 

individual’s anatomic and physiologic characteristics and the nature of the 

acceleration profile. The maximum +Gz level, exposure duration and the rate of 

onset of the +Gz are important determinants of the risk of neurologic compromise, 

cardiac rhythm disturbances and musculoskeletal (especially neck) injury. Onset-
rates greater than 0.1G/second are considered rapid since they exceed the ability 

of the cardiovascular system to fully respond to preserve adequate central nervous 

system blood flow. Rapid-onset rates of 1.0G/second and greater can result in GLOC without visual warning symptoms. Conservative relaxed, unprotected 

tolerance of completely healthy humans to +Gz acceleration is considered 

approximately +3Gz (normal range 3.1 to 4.0) for rapid-onset profiles and increases 

to approximately +3.5Gz (normal range 3.7 to 5.6) with gradual-onset profiles. 

Individuals with compromised cardiovascular anatomy or function may have 

reduced tolerances. Care should be exercised with rapid-onset profiles to +3Gz or 

more, sustained for 5 seconds or longer. 
MEDICAL HISTORY ASSESSMENTS of PASSENGERS in SUBORBITAL 

AEROSPACE FLIGHTS 

These prospective aerospace passengers should complete a questionnaire about 

their medical history of any of the following conditions: 

• Otitis, sinusitis, bronchitis, asthma, or other respiratory disorders 

• Dizziness or vertigo 

• Fainting spells, or any other loss of consciousness 

• Seizures 

• Tuberculosis 

• Surgery and other hospital admissions 

• Visits to physicians in the last 3 years 

• Recent significant trauma 

• History of decompression syndrome (DCS) 

• Anemia or other blood disorders 

• Heart or circulatory disorders, including implanted pacemaker or defibrillator 

• Mental disorders 

• Claustrophobia 

• Attempted suicide 

• Use of medications 

• Alcohol or drug dependence or abuse 

• Date of last menstrual period, current pregnancy, recent post-partum (less than 

6 weeks), or recent spontaneous or voluntary termination of pregnancy 

• Diabetes 

• Cancer 

• Rejection for life or health insurance 
MEDICAL HISTORY ASSESSMENTS of PASSENGERS in ORBITAL 

AEROSPACE FLIGHTS 

These prospective aerospace passengers should complete a questionnaire about 

their medical history of any of the following conditions: 

• Otitis, sinusitis, bronchitis, asthma, upper respiratory infections, or other 

respiratory disorders 

• Allergies 

• Dizziness or vertigo 

• Significant motion sickness requiring medication 

• Fainting spells, or any other loss of consciousness 

• Seizures, convulsions, epilepsy, stroke, muscular weakness, or paralysis 

• Tuberculosis, hepatitis, AIDS, or other chronic infectious disorder 

• Surgery, recent or remote, or other admission to hospital 

• Recent significant trauma 

• Anemia or other blood disorders 

• Heart or circulatory disorders, including implanted pacemaker or defibrillator 

• Uncontrolled high or low blood pressure 

• Mental disorders (including depression, anxiety, fear of flying, fear of heights, 

fear of closed spaces, fear of open spaces, etc.) 

• Attempted suicide 

• Use of medications 

• Alcohol or drug dependence or abuse 

• Date of last menstrual period, current pregnancy, recent post-partum (less than 

6 weeks), or recent spontaneous or voluntary termination of pregnancy 

• Severe hay fever or allergies 

• History of pneumothorax (collapsed lung) 

• Kidney stones or blood in urine 

• Gallstones or gallbladder disease 

• Diabetes 

• Cancer 

• History of radiation treatment or occupational exposure to radiation 

• Rejection for life or health insurance 

• History of decompression syndrome (DCS) 

• History of previous space flights 
PHYSICAL EXAMINATION ASSESSMENTS of PASSENGERS in ORBITAL 

AEROSPACE FLIGHTS 

These prospective aerospace passengers should receive a general physical 

examination that includes: 

• Vital signs (heart rate, respiratory rate, temperature, blood pressure) 

• Head, face, neck, and scalp 

• Nose, sinuses, mouth, throat, ears (including eardrum integrity and function, 

Eustachian tube function) 

• Ophthalmological evaluation (including pupil function, ocular motility) 

• Lungs and chest 

• Heart (including precordial activity, rhythm, sounds, murmurs) 

• Peripheral vascular system 

• Abdomen and viscera (including hernia) 

• Genitourinary system 

• Upper and lower extremities 

• Spine 

• Lymphatics 

• Rectal, pelvic, and breast examination should be performed only if indicated by 

medical history 

• General neurological evaluation 

• General psychiatric evaluation (appearance, behavior, mood, communication, 

and memory) 
MEDICAL TESTING of PASSENGERS in ORBITAL AEROSPACE FLIGHTS 

Prospective passengers in Orbital Aerospace Flights should complete the following 

general medical tests: 

• Routine hematology 

• Clinical chemistry (serum) 

• Urinalysis 

• Resting EKG 

• Chest X-rays (PA & lateral) 

• Visual acuity (corrected) 

• Pregnancy testing (optional) 

• Hearing (conversational voice at 6 ft) 

• Tympanometry and/or tonometry (if clinically indicated) 

• Pulmonary function testing (if clinically indicated) 
MEDICAL CONDITIONS THAT MAY CONTRAINDICATE PASSENGER 

PARTICIPATION in SUBORBITAL or ORBITAL FLIGHTS 

In general, medical conditions that MAY BE contraindicated for aerospace flights 

include: 

Any deformities (congenital or acquired), diseases, illnesses, injuries, infections, 

tumors, treatments (pharmacological, surgical, prosthetic, or other), or other 

physiological or pathological conditions that: 1) may result in an inflight medical 

emergency, 2) may result in an inflight death, 3) may compromise the health and 

safety of the passenger or other aerospace vehicle occupants, and/or the safety of 

the flight, 4) may interfere with the proper use (don and doff) and operation of 

personal protective equipment, or 5) may interfere with inflight emergency 

procedures or emergency evacuation, or 6) may have a negative effect on the 

passenger's health as a result of exposure to aerospace flight. Any medical 

condition that may result in an unexpected inflight medical emergency represents a 

potential risk to the safety of the flight. 

An established clinical diagnosis or finding of any of the following conditions may 

contraindicate participation in aerospace flight and should be further evaluated on 

a case-by-case basis: 

• Acute or chronic use of any medication (prescription and/or non-prescription), 

drug, or substance 

• Cancer 

• Severe trauma or invasive medical procedures (diagnostic or therapeutic) 

associated with significant functional deficit 

• Severe acute or chronic infections or communicable/contagious diseases 

(including blood borne infectious diseases) 

• History of individual exposure to ionizing radiation (single dose or cumulative) 

that exceeds the maximum exposure limit of 5 mSv in 5 years recommended by 

the International Commission on Radiological Protection. 

• Current pregnancy, recent post-partum (less than 6 weeks), or recent 

spontaneous or voluntary termination of pregnancy 

• Any psychiatric, psychological, mental, or behavioral disorder that would cause 

an individual to become a potential hazard to him/herself or to others. 

• Any other diseases, illnesses, deformities, injuries, infections, tumors, or 

treatments that may result in significant functional impairment or that may be 

aggravated by exposure to environmental or operational stress factors of 

aerospace flight. 
DISPOSITION of PROSPECTIVE AEROSPACE PASSENGERS WHO HAVE 

MEDICAL CONDITIONS THAT MAY CONTRAINDICATE PARTICIPATION in 

AEROSPACE FLIGHT 

Prospective aerospace passengers who have medical conditions that may 

contraindicate participation in aerospace flight could be given medical clearance, 

on a case-by-case basis, by a physician retained by the operator and who is 

trained or experienced in aerospace medicine. 

Based on the specific nature of the medical condition, an individual should be 

temporarily prohibited from participation in aerospace flight until the medical 

condition resolves or until it can be effectively brought under medical control and it 

is no longer likely to result in: 1) Inflight medical emergency, 2) Inflight death, 3) 

Compromising the health and safety of the passenger or other aerospace vehicle 

occupants, and/or the safety of the flight, 4) Interference with the use (don and 

doff) and operation of personal protective equipment, or 5) Interference with inflight 

emergency procedures or emergency evacuation, or 6) Having a negative effect on 

the passenger's health as a result of exposure to aerospace flight. Prospective 

passengers should be cautioned on the potential hazards to health of aerospace 

flight, including the hazards of exposure to solar and cosmic radiation, 

acceleration, and microgravity. It must also be recognized that no conclusive data 

exist concerning the potential adverse physiologic and pathologic effects of space 

flight on infants or young children. For this reason, operators may wish to establish 

a minimum age for passengers participating in aerospace flights. 
PRE-FLIGHT MEDICAL INTERVIEW and PHYSICAL EXAMINATION 

REQUIREMENTS FOR PASSENGERS in ORBITAL AEROSPACE FLIGHTS 

Prior (within one to two weeks) to the actual departure of an orbital commercial 

aerospace flight all passengers should be subjected to an abbreviated pre-flight 

medical interview and physical examination. The purpose of this pre-flight medical 

screening is to ensure that these passengers have not developed medical 

conditions that may have occurred since the last medical clearance was issued. 

Such a pre-flight medical screening should include vital signs and a brief medical 

history and physical examination concentrating on the following: eye, ear, nose, 

throat, cardiopulmonary, gastrointestinal tract, musculoskeletal, and neurological 

systems. A brief mental status assessment should also be obtained. Because of 

the potential hazards of aerospace flight (including exposure to solar and cosmic 

radiation, acceleration, and microgravity), it is recommended that a female of childbearing age be offered a pregnancy test. Operators may wish to consider 

excluding pregnant women from participating in aerospace flights. 

Jon Jordan, M.D., J.D. 

Melchor Antuñano, M.D., M.S.