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Advanced Analyzers for Monitoring Submarine Atmosphere


TECHNOLOGY AREA(S): Sensors, Electronics, Battlespace 

OBJECTIVE: Develop advanced analyzer technology to improve performance and reduce maintenance costs of current atmosphere monitoring systems. 

DESCRIPTION: Many spectrometry tools are commercially available for analyzing gas constituents, including ion mobility, optical, and mass spectrometry, with many variations in each technique. Advances have been made in all spectrometry technologies, with great improvements in optical spectrometry versatility and select ability, thanks to mid-infrared (IR) laser and other material developments. U.S. Navy submarine atmosphere monitoring has remained largely unchanged since the 1970’s with magnetic sector mass spectrometry and IR spectrophotometry the primary techniques employed. Listed below are the five common gases that are monitored at the percent level (partial pressure measured in torr), and the 14 contaminants that are measured at the parts per million (PPM) level (partial pressure measured in millitorr). While trace contaminants are continuously reviewed, and monitoring requirements are subject to change, the five gases measured in torr are unlikely to change. The Central Atmosphere Monitoring System (CAMS) IIA mass spectrometer is capable of measuring ions between 2 and 210 atomic mass units (AMU). The IR spectrophotometer identifies carbon monoxide because it cannot be detected by mass spectrometry in a nitrogen-rich atmosphere, due to the two gases having the same atomic mass. Although the combination of mass spectrometry and IR spectrophotometry have provided reliable service to the Navy for 40 years, the system is costly to maintain, and not flexible enough to meet all future capabilities. The Navy is looking to identify advanced analyzer technologies that have emerged since the development of CAMS, such as long-life, solid-state lasers or energy detectors, in order to improve performance and reduce maintenance costs of current atmosphere monitoring systems. Gases measured by CAMS IIA: GASES MEASURED IN PERCENT (torr): Carbon Dioxide Hydrogen Nitrogen Oxygen Water Vapor GASES MEASURED IN PPM (millitorr): Acetone Aliphatic Hydrocarbons Aromatic Hydrocarbons Benzene Carbon Monoxide Methanol Methyl chloroform Refrigerant 114 Refrigerant 12 Refrigerant 134A Silicone Stibine Trichloroethylene Cost to maintain: The high vacuum and sophisticated tuning required of mass spectrometry are the main factors in the current system’s high maintenance costs. Many common failures require entering the vacuum boundary of the mass spectrometer for repair, and are outside of the operators’ technical capabilities. The cost to repair the mass spectrometer averages $145,000 per unit, not including ancillary costs such as packaging, shipping, and administration. Assuming there are no premature failures, policy requires overhaul of each system every three years at the same cost as repair. The goal of this research effort is to halve the frequency of factory overhauls, and reduce annual maintenance costs to under $20,000, including amortized factory overhaul and operator maintenance costs. This effort seeks a technology that minimizes the number of moving mechanical parts, unless those parts can be shown to require no more frequent maintenance than the factory overhaul (at least six years). Capabilities: The naval engineering directorate promulgates atmosphere-monitoring requirements based on recommendations from the naval medical community, as well as engineering concerns. Mass spectrometry meets existing submarine atmosphere monitoring requirements; however, these requirements are not static. As submarine atmospheres are surveyed continuously, and as the medical and engineering communities’ interest in atmospheric contaminants evolves, measuring new gases—such as acrolein, formaldehyde, and ozone—will become required. These new gases might provide transport challenges, in addition to detection challenges. This research effort seeks a technology that can be tuned to new gases through software upgrades, or minimal component changes (e.g., replacing laser wavelength) that do not affect overall system configuration or footprint. The initial start time from a cold condition should not exceed the current threshold for CAMS IIA, eight hours, and ideally is under one hour. Individual reading response time should not exceed 120 seconds, but ideally should be under one minute. Integration: The incumbent system includes sample control, power, and data distribution systems. The technology sought by this effort must be capable of integration in the incumbent cabinet or as a standalone system. The enclosure should be a rectangular prism, with dimensions designed to fit in a space with a 16-inch by 16-inch footprint and a height of 8 inches, and be capable of mounting in different orientations. Input power is 115VAC whether integrated in incumbent cabinet or operated independently. Sample flow is continuous 1-6 SCFH in the incumbent cabinet. The technology can modulate flow, but must vent to the same type of connection as used for inlet from, for rejection by the incumbent system. If mounted standalone, the technology must have a sample system that requires no more frequent than annual material maintenance (flow adjustment no more than weekly). The technology must have local display for operation, analysis results, fault isolation, maintenance, and troubleshooting, and be capable of providing the same data as well as historical data through an external data connection. 

PHASE I: Investigate processes to analyze gases required on U.S. Navy submarines; then develop a concept to determine the capability of the technology to perform its function within the conditions specified. Demonstrate, through analysis and/or simulation, the feasibility of the concept in meeting Navy needs and establish that the material can be reasonably developed into a useful system for the Navy. The Phase I Option, if awarded, should include the initial layout and capabilities description to build a prototype in Phase II. Develop a Phase II plan. 

PHASE II: Based on the results of Phase I and the Phase II Statement of Work (SOW), develop and deliver a prototype for testing on a lab scale under the appropriate conditions to simulate a submarine environment. Evaluate the prototype to determine its capability in meeting the performance goals defined in Phase II SOW and the Navy requirements for monitoring gases and contaminants. Using evaluation results, finalize a system configuration that will meet Navy requirements. Prepare a Phase III development plan to transition the technology to Navy use. 

PHASE III: Support the Navy in transitioning the technology to Columbia Class submarines. The final product will be capable of operation in an existing atmosphere monitoring system cabinet or as a standalone system. The system will be capable of measuring required gases, and meet maintenance requirements. The product will meet all relevant incumbent qualification testing, including shock, vibration, electromagnetic interference (EMI), humidity, and noise, per references (6) through (10), respectively; ship’s motion (demonstration of operation with inclination up to 45 degrees from vertical in any direction), temperature (operation over the temperature range from 10°C to 46°C), humidity (operation in ambient pressure ranging from 450 torr to 900 torr, absolute) cross-sensitivity (demonstration of operation within specification when a mix of all gases analyzed is applied to the system), stability (demonstration that once full value readings are indicated, drift of readings must not exceed half of limits during three hours of continuous application of the mix of all gases analyzed),and endurance (continuous unattended operation for 720 hours). Power, dimensions, and weight limits will be determined by a trade study that includes the number of gases that the system is capable of indicating. Atmosphere monitoring requirements are continuously evolving in the private sector. Atmosphere quality is regulated in workplaces, industrial effluent (such as smokestacks), and outdoors. Many contaminants of interest to the U.S. Navy submarine force are shared with private sector employers. Technology meeting the requirement for flexibility described in the description will be capable of meeting private sector requirements. Some examples of private sector applications include monitoring of combustion gasses in pre- and post- fire applications, monitoring of CO2 and other emissions from factories, power plants, cars, or other private industry applications, and detection of gas levels and leakages in various industrial environments. 


1: Watson, J. Throck & Sparkman, O. David. "Introduction to Mass Spectrometry: Instrumentation, Applications, and Strategies for Data Interpretation, 4th Ed." Chichester: Jonh Wiley & Sons, 2007.

2:  Werle, P., Slemr, F., Maurer, K., Kormann, R., Mucke, R. and Janker, B. "Near- and Mid-Infrared Laser-Optical Sensors for Gas Analysis." Opt. Las. Eng. 37(2–3), 101–114 (2002).

3:  "Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants." Washington, DC: The National Academies Press, 2007.

4:  "Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 2." Washington, DC: The National Academies Press, 2008.

5:  "Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants: Volume 3." Washington, DC: The National Academies Press, 2009.

6:  MIL-S-901D, Amended with Interim Change #2, Shock Test, H.I. (High Impact)

7:  Shipboard Machinery, Equipment and Systems, Requirements for

8:  MIL-STD-167-1, Mechanical Vibration for Shipboard Equipment (Type I - Environmental and Type II - Internally Excited)

9:  MIL-STD-461F, Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment

10:  MIL-HDBK-2036, Preparation of Electronic Equipment Specifications

11:  10. MIL-STD-740-2, Structure-borne Vibration Acceleration Measurements and Acceptance Criteria of Shipboard Equipment

KEYWORDS: Atmosphere Analysis; Laser Spectroscopy; Analytical Chemistry; Atmosphere Monitoring On Submarines; CAMS IIA; Submarine Atmosphere 


Jay Smith 

(215) 897-7250 

Matthew Smith 

(215) 897-7768 

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