Effective and Environmentally Compliant Cleaner -

Solstice® Performance Fluid

On January 1, 2015, the United States Environmental Protection Agency identified exemptions on the continued use of the 

hydrochlorofluorocarbon (HCFC)-225ca and -225cb. As these solvents are commonly used in cleaning and verification of aerospace 

propulsion systems using liquid and gaseous oxygen, the NESC supported the Agency initiative to identify and characterize 

acceptable alternate fluids. Honeywell’s Solstice® Performance Fluid (PF), PF-high purity (HP), and PF-HP spray are an effective 

nonflammable cleaning solution system, with a favorable toxicity profile and low environmental impact. Solstice PF is suitable for 

electronics, metal, and precision cleaning. It can be used in vapor degreasing equipment and may be dispensed with a propellant 

to create an aerosol contact cleaner. Solstice PF has been shown to have negligible ozone depletion and a global warming 

potential of 1. With these characterized environmental and solvency properties, Solstice PF, PF-HP, or PF-HP spray may be an 

excellent choice for a variety of cleaning applications.

NASA Engineering and Safety Center Technical Bulletin No. 20-02

National Aeronautics and Space Administration

www.nasa.gov For information, contact Steven J. Gentz at steven.j.gentz@nasa.gov.

Cleaning Capabilities: The solubility characteristics allow 

for Solstice PF (NVR < 10 PPM) and PF-HP (NVR< 2 PPM) to be 

used to dissolve a number of typical soils that are encountered 

in military and aerospace cleaning operations.

Non-Flammable: Solstice PF does not exhibit flashpoint or 

vapor flame limits. It was determined not to have vapor flame 

limits at temperatures to 100°C (212°F) using an ASTM E 681 

apparatus.

Oxygen System Cleaning: Solstice PF, PF-HP, and PFHP spray are well suited for oxygen line cleaning as they 

effectively remove contamination and then can be completely 

dried. Solstice PF-HP and PF-HP spray passed the mechanical 

impact tests per ASTM D 2512- 82, has an oxygen-enriched 

autoignition temperature of 182°C (360°F) at 13.8 MPa (2,000 

psig) per ASTM G 72, and Heat of Combustion of 2,448 kcal/kg 

(4,403 BTU/lb) per ASTM D240.

Compatibility: Solstice PF is compatible with metals commonly used in aerospace and military, and in all cases the 

metals tested per ASTM F483 indicated no solvent breakdown 

or acid formation.

Implementation Consideration: Solstice PF characteristics compared to other currently available cleaning solutions:

• Low solvent loss due to:

- High heat of vaporization, and low surface tension - 

 improved wetting characteristics and reduced drag-out loss

- Recovery potential - distillation and carbon recovery

• Reduced energy requirements for processing

• High solvency, not a high-cost filler - reduces or

 eliminates blending

• High wetting index for removal of particulate matter

 from complex parts

• No post-process residue removal

• Potential drop-in alternative in aerosol cleaners

The unique solubility characteristics, high performance, 

nonflammability, stability, low toxicity, and environmental 

compliant properties of Solstice PF and PF-HP allow for use 

in a wide variety of applications from oxygen line cleaning 

to degreasing. NASA Cleaning Facility Conversion: Cleaning 

facilities at SSC and MSFC have converted to Solstice PF 

with minimal issues. Points of contact at these facilities are 

Rick Ross (harold.r.ross@nasa.gov, 228-688-2353) and Mark 

Mitchell (mark.a.mitchell@nasa.gov, 256-544-5860).

References

1. Replacement of Hydrochlorofluorocarbon-225 Solvent for 

Cleaning and Verification Sampling of NASA Propulsion Oxygen

Systems Hardware, Ground Support Equipment, and Associated 

Test Systems, NASA/TP-2015-218207

2. Solvent Replacement for Hydrochlorofluorocarbon-225 for 

Cleaning Oxygen System Components, NASA/TM-2017-219687

3. ASTM STP 1596, “Flammability and Sensitivity of Materials 

in Oxygen-Enriched Atmospheres, 14th Volume. (West Conshohocken, PA: ASTM International, 2016)

04/17/2020