1、Lessons Learned Entry: 1178Lesson Info:a71 Lesson Number: 1178a71 Lesson Date: 2001-02-01a71 Submitting Organization: HQa71 Submitted by: David M. LengyelSubject: Crew Health/Radiation Monitoring/Neutron Dosimetry Description of Driving Event: Scheduled Deployment of Neutron Dosimetry Aboard the Int
2、ernational Space Station (ISS)Lesson(s) Learned: Even though the most significant unknown in crew composite radiation exposure may be the contribution of neutrons, the Evolutionary Plan for the Crew Health Care System (CHeCS) only lists a neutron monitor as a “Future Medical Requirement,“ and a proj
3、ect to fly a neutron detector is not planned until Increment 2.Recommendation(s): Accelerate the development of effective and reliable personal and area neutron dosimeters.Evidence of Recurrence Control Effectiveness: Code M - Concur: Crew and area dosimetry now include the use of four distinct ther
4、mo luminescence crystals of distinct sensitivity to neutron effects. This approach allows for the identification of the fraction of the crew radiation dose due to low-energy neutrons.The tissue equivalent proportional counter (TEPC) was developed in the 1950s to measure radiation fields. NASA develo
5、ped and has flown a flight version of the TEPC for 10 years. All STS missions and the ISS include an active TEPC that detects neutrons. And charged particles in the relevant energy range with good efficiency. However, the TEPC cannot distinguish neutrons from charged particles.Provided by IHSNot for
6、 ResaleNo reproduction or networking permitted without license from IHS-,-,-A project to fly the Bonner Ball Neutron Detector in collaboration with the National Space Development Agency of Japan is planned beginning on Increment 2. This instrument will provide a spectrum of the neutron energies inci
7、dent on the ISS. The neutron spectrum analysis will allow determination of proper weighting of the TEPC data.The development of active personnel monitor(s) using silicon detector technologies is being evaluated for flight use on Shuttle and ISS.In addition, NASA uses state-of-the art radiation trans
8、port codes that include neutron reaction processes. These codes have become the standard engineering tool used for spacecraft design.Documents Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Aerospace Safe
9、ty Advisory Panela71 Flight Operationsa71 Hazardous/Toxic Waste/Materialsa71 Human Factorsa71 Medicala71 Payloadsa71 Personal Protective Equipmenta71 Research & Developmenta71 Risk Management/AssessmentAdditional Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Info: a71 Approval Date: 2002-03-18a71 Approval Name: Bill Loewya71 Approval Organization: HQa71 Approval Phone Number: 202-358-0528Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
