### Comments on U.S.EPA **40CFR82 Protection of Stratospheric Ozone;**

**Amendments to the Section 608 Leak Repair Requirements ;**  **Proposed Rule**  Docket ID Number: EPA

- HQ
- OAR
- 2003
- 0167 Federal Register Vol. 75, No. 240, Wednesday , December 14, 2010/Proposed Rules
**De finitions**  **§82.152 : Leak**  **Rate Leak Rate Calculation**  **Method**

 The leak rate calculation needs to have a time normalization factor to reflect the annual leak trigger rates. The proposed rule replaces the existing two annual leak rate calculation methods with a single rolling average method that will not accurately reflect the annual leak rate in some cases. The intent of the trigger rate in the rule is to trigger repair when the magnitude of leaks exceed annual leak thresholds. For leaks that occur longer than a ye ar apart or if the pounds of refrigerant added reflect the total additions in the past 365 day s, the proposed formula works well. However, when leaks occur less than a year apart and the equation uses the number of pounds of refrigerant added si nce the last repair it does not reflect the magnitude of the annual leak rate of the s ys tem. An annual normalization factor is needed. For example, in the following h ypothetical situation because there is no annual normalization built into the proposed l eak rate calculation, the annual leak rate appears lower than actual. Given a 100 pound charge, and a 15 pound leak in 180 day s since the last repair, the leak rate would be calculated using the proposed equation as: (15 pounds leaked / 100 pound full charge) * 100% = 15% leak rate. However, if normalized to an annual leak rate, it is: (15 pounds leaked / 100 pound full charge) * (365 day s per year / 180 day s since the last repair) * 100% = 30% annual leak rate. When normalized to an annual leak rat e, the leak rate increases from 15% total charge in six months in this example, to a 30% annual leak rate, better reflecting the magnitude of the leak. Therefore, the leak rate method as proposed does not reflect actual annual leak rates for repairs made less than one year before the leak rate was calculated. The leak rate calculation method should be revised to the following to accuratel y reflect annual leak rates:(pounds of refrigerant added since last successful follow

- up verification test (or during the past 365 day s if that period is greater than one ye ar) 365 day s per year Leak Rate = ___________________________ X ______________ X 100% (% per ye ar) day s since last

Pounds of refrigerant in full charge successful follow

- up verification test up to 365 **Definitions §82.152 : Refrigerant** 

 The high

- global warming potential non

- ODS refrigerants (substitutes for Class I and Class II refrigerants) should be included in the rule’ s definition of refrigerants. Phasing out of various ODS compounds ( as required by Montreal Protocol and U.S. Clean Air Act Amendments of 1990 ) and the retrofit provisions of the current rule will likely cause facilities to transition into ODS substitut e refrigerants such as HFCs , which, although not harmful to the stratospheric ozone layer, are potent greenhouse gases (GHG) with high global warming potential (GWP). Currently , HFCs comprise 48 percent, or almost half of all refrigerant greenhouse gas em issions. Therefore, to reduce GHG emissions from refrigerant sources, it is important that HFCs and other non

- ODS substitutes be included fully as regulated refrigerants in the proposed rule amendments
. By 1 2 020, HFCs are expected to comprise full y 80 percent of all refrigerant GHG emissions, and by

2030, HFCs will comprise 99 percent of all refrigerant GHG emissions. Considering the U.S.EPA Endangerment Finding on GHGs , it does not seem reasonable to transition from one class of high

- GWP compounds into an other and not implement controls on the second class of compounds. Moreover , the purpose and scope ( §82.150) as well as the no

- venting etc. provisions of the current rule appl y to all refrigerants including the ODS substitute refrigerants ; therefore the se refrigerants should also be subject to the required practices such as leak repair, retrofit and retirement, and recordkeeping requirements of the rule
. **Required Practices §82.156 (i)**  **: Repair of Leaks and Leak Repair Trigger Rates Repair of Leaks at Fitt**  **ings (page 78568)** 

 All leaks should be required to be repaired irrespective of their sources. The proposed allowance discussed on page 78568 of the Federal Register posting that leaks in appliance valves, seals, gaskets, and other fittings need not be a ddressed during
1 U.S. EPA Vintaging Model estimates of CFC, HCFC, Halon, and HFCs, 2010

- 2030; as estimated in 2008leak repair should not be included in the amended rule. While it is not possible to prevent

all leaks; valves, seals, gaskets, and other fittings can be significant leak locations particularl y where there is a rotating or sliding shaft as in a valve or shaft seal or other points of motion or stress. **Definitions §82.152: Follow**  **- up Verification Test**  **Required Practices §82.156(i) Follow**  **- up Verification Test** 

 The requirement that the follow

- up verification test be conducted no sooner than 24 hours a fter the repairs are completed may be unnecessary
. The intent that the follow

- up verification test be conducted after the s ys tem has returned to normal operating conditions is an important stipulation to en sure that the repairs will hold . H owever, based on industry input, man y s ys tems are able to return to normal operating conditions much sooner than 24 hours. The refore the intent of the requirement can be met in some cases during the same service repair visit , making the mandatory 24
- hour waiting time not necessary
. **Definitions §82.152: Retire (new definition)** 

 The intent of the EPA is somewhat unclear; while repairs are at the component level, if a repair is unsuccessful the retirement requirement is that the entire appliance must be scrapped ev en if all but a small component is leak tight and functions well. The requirement that retire means that an entire appliance must be removed from service is likely to cause unnecessary

expense and time when removal from service of a specific component that has proven to be unrepairable would likely serve the same function. Retire would be better defined as “ the permanent removal from service of a refrigeration sy stem, or component, rendering it unfit for use by the current or any

future owner or operator ”
.

Contact: Pamela Gupta, Greenhouse Gas Reduction Strategy Section Manager, (916) 327

- 0604, pgupta@arb.ca.gov Ken Bowers (919)323

- 1510, kbowers@arb.ca.gov http://www.arb.ca.gov/cc/reftrack/reftrack.htm