UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C

. 20460

Mr
. Richard H. Maruya A.S. Trust & Holdings 44-129 Mikiola Drive Kaneohe, Hawaii 96744 

## MAY 1 5 2013 OFFICE OF AIR AND RAD IAT ION

Re: Incomplete SNAP Submission for R-443A (HCR-188C2) for Residential Air Conditioning Dear Mr. Maruya: Thank you for A.S. Trust & Holdings' SNAP application to the Environmental Protection Agency (EPA) received on February 13,2013. The Agency has reviewed the information in the letter and determined that the Significant New Alternatives Policy (SNAP) program submission for R-443A in residential air conditioning (A/C) is incomplete. The following informat ion is necessary in order to allow the Agency to move forward with the A.S. Trust & Holdings, Inc.'s SNAP submissions for R-443A in residential air conditioning
. 1. Charge Size. Throughout your SNAP application for R-443A you estimate varying charge sizes (i.e., Part I Section 4(b), Part II Section 2(b) and the risk assessment). Please clarify your typical charge sizes and provide information on the maximum charge sizes, minimum and maximum room sizes and equipment capacity for each ofthe end uses applications in your submission. Below is one option for providing this information. a. Please clarify what EPA requirement you are referencing in Part I Section 4(b) of you application when you state, "
.. .while meeting the EPA regulated maximum charge for a flammable refrigerant in new systems." R

-443A Application Typical Maximum Minimum Typical Room Equipment Charge Size Charge Size Room Size Size Capacity Residential splitsystem A/C units Residential heat pump Portable room A/C

2
. RiskAssessment. Please provide additional information and responses to the following questions regarding your risk assessment.

Internet Add ress (URL) • http // www. e pa .gov Recyc l ed/Recycla bl e • Pri nted with Vegetabl e O il Based I nks on 100% Postcon sum e r. Process C hl ori ne Free Recycled Papera. What are the risks ofrefrigerant release and offire in a furnace room or utility closet that contains the indoor portion ofa heat pump or residential A/C splitsystem? 1. Please provide fault trees related to a catastrophic release in a furnace room, utility/mechanical closet or crawl space ofa home for split systems and for heat pumps. 11. What differences, ifany, would there be in risk for an A/C system coinstalled with a gas furnace or electric heater? Please provide information on both types of equipment. b. The modeling ofconcentrations you conducted assumes that a release from a heat pump or split system disperses evenly throughout the entire house immediately upon release. Please explain why the release is modeled this way instead of modeled as a release into one room followed by dispersion into subsequent rooms . How do the risk calculations and the maximum concentrations change for a residential release ifthe risk assessment is revised by: 1. Assuming that during the catastrophic release scenario, all the refrigerant from the split system or heat pump initially leaks in a utility closet or room and then over time migrates into neighboring rooms, and then throughout the entire building? 11. Assuming that the safety valve does not operate as intended and does not reduce the maximum charge release? 111. Both ofthe assumptions above? c. Please include information on potential impacts ofhuman exposure to refrigerant released during servicing or charging. d. Please explain the calculations and assumptions behind the fault tree condition "Sufficient Leak Occurs During Servicing" on page 217 ofyour application. e. What is the basis or source for the assumption in the risk assessment that for a split A/C system, 71.9% ofrepairs will be to the outdoor unit? 3. Safety Valve. In which section ofthe refrigerant circuit should the safety valve be installed to mitigate risk? Please provide a schematic diagram ofa refrigerant circuit for each ofthe three types ofequipment covered in the submission, and indicate where the safety valve should be placed. 4
. Environmental Release andDisposal atManufacture. Please describe the process for manufacturing, and assembling A/C equipment using R-443A, detailing whether it is automated or manual and whether or not workers use personal protective equipment. Also , please describe the anticipated waste management practices for manufacture of household A/C systems using R-443A, including whether or not workers use personal protective equipment during clean up. Please provide this information on all three equipment types. 5. Occupational and Consumer Exposure. Please clarify whether the A/C equipment is expected to be charged during manufacture, installation or a combination ofboth. Furt her, ifcharging occurs at the manufacture site, is the unit entirely sealed by the timeit reaches the end-use site? What are typical values for ventilation in air changes per hour at the charging location? Please provide this information on all three equipment types. 6. Additional Resources. Please provide a copy ofthe Colbourne 2001 study, Risk Assessment of Flammable Refrigerants in Room Air Conditioners, referenced in the risk assessment. 7. CBI Claims. Ifyou wish to claim any ofthe information submitted in response to the above requests as confidential business information (CBI), please provide two copies of your response, one containing CBI and one with CBI removed. Here is a summary ofinformation concerning your submission: Substitute name: R-443A (HCR-188C2) Substance(s) the substitute will replace: HCFC-22 Sector: Refrigeration and Air Conditioning End-uses: Residential and light commercial air conditioning and heat pumps Applications: Residential split-system A/C units, residential heat pumps, and portable (floor model) room 

### AJC New or retrofit usage: New Date received: February 13,2013 Status of submission: Incomplete Responses to these questions would be helpful for our review. The information can be submitted via electronic mail or hard copy. Ifyou have questions about your submission, please contact our SNAP Coordinator, Rebecca von dem Hagen at (202) 343-9445 or vondemhagen.rebecca@ epa. gov. Sincerely,
Cindy Newberg Alternatives and Emissions Reduction Branch Stratospheric Protection Division