1 

### Dave, Apurva

From: VonDemHagen, Rebecca

Sent: Monday, June 10, 2013 4:31 PM

To: riskscicom@aol.com; richard@astrust.com

Cc: Sheppard, Margaret; Newberg, Cindy Subject: RE: Incompleteness Letter RE: Use of R-443a in Resi dential Air Conditioning and Heat Pump Systems



### Mr. Whitmyre and Mr. Maruya,

Thank you for taking the time to outline your appro ach. For your response to question 1, please be sur e to include both the minimum and typical room sizes. We will not be able to provide our formal input until the addition al information is provided. We look forward to seeing your responses.

Best Regards,

Rebecca von dem Hagen Stratospheric Protection Division Office of Atmospheric Programs U.S. Environmental Protection Agency (202) 343-9445 vondemhagen.rebecca@epa.gov

From: riskscicom@aol.com [mailto:riskscicom@aol.com]
Sent: Tuesday, May 28, 2013 10:41 PM
To: Newberg, Cindy
Cc: VonDemHagen, Rebecca; Sheppard, Margaret; richard@ astrust.com; engineeringink@earthlink.net Subject: Incompleteness Letter RE: Use of R-443a in Residen tial Air Conditioning and Heat Pump Systems

Cindy:

Thank you for your May 15, 2013 letter to Richard M aruya outlining your information needs for the SNAP application regarding the use of R-443a in central residential air conditioning systems, residential heat pump sys tems, and portable air conditioning units. As I have been the technica l lead on exposure and risk assessment issues, Mr. Maruya has authorized me to communicate directly with you to c larify your information needs in this area, so that we may efficiently and effectively convey the requested information to you in as short a time frame as possible. Because some of your questions ask us to address additional exposure sce narios, wherein we would need to document the speci fic assumptions and parameter values used in the new exposure model ing work, we feel that these questions would best b e addressed in the form of a supplemental report.

To clarify our approach to answering the 7 question s posed in your May 15, 2013 letter, I have outline d our approach below:

(1) Charge size . You have asked for typical, minimum, and maximum charge sizes, typical room sizes, and equipment capacity. I like the tabular approach that you have suggested, and I will work closely with our team e ngineer to better characterize the ranges of use conditions, to the e xtent that equipment specifications for representat ive units are available. We have completed bench scale testing of a generic refrigeration system to supplement our t ests on actual split system residential air conditioning and heat pump s ystems. The bench scale testing provides a quantita tive basis for calculating the R-443a charge amount as a percentag e of a "full" R-22 charge, which is normally specif ied on a unit's specifications plate. We will document typical room size based on survey data, such as that provided b y the National Association of Home Builders (NAHB).2 (2) Risk assessment

. In order to answer parts (a), (b), and (c) of you r question #2, we propose conducting additional indoor air modeling using MCCEM. We propose perform ing multi-zone modeling to address your subquestion (b). The focus of the 3 sub-questions appears to be on furna ce room or utility closet scenarios. We will attemp t to match room volume and ventilation rates to what is normally re quired by existing building codes for utility close ts and furnace rooms, to the extent applicable. New fault-tree calculatio ns and diagrams will be developed to address the ne w scenarios you have suggested. Sub-questions (d) and (e) can be si mply addressed in a few sentences of text.

(3) Location of safety valves . We will provide the requested schematics, and wil l also provide explanatory text.

(4) Environmental releases and disposal at manufacture . We will work with our engineering team and potent ial manufacturers to elaborate more on the issues you h ave raised.

(5) Occupational and consumer exposures . Our current understanding is that the air conditi oning and heat pump units will be charged and sealed at the equipment manufacturin g site. We will attempt to obtain ventilation infor mation and requirements for similar types of facilities as a m easure of ventilation rates.

(6) References . We will attach a full copy of the Colbourne 2001 reference to the supplemental report.

(7) CBI claims . We will provide both a CBI report and a non-CBI r edacted report.

We would kindly appreciate a response from the Agen cy as soon as possible to indicate its concurrence with our proposed approach, or to indicate where alternative approaches, data, or analysi s are required. I thank you in advance for a timely response.

Regards,

Gary Whitmyre, D.A.B.T. Whitmyre Research 2111 Wilson Blvd., Suite 600 Arlington, Virginia 22201

(703) 597-9796 riskscicom@aol.com