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Subpart SS—Electrical Equipment Manufacture or Refurbishment

§ 98.450 Definition of the source category.

The electrical equipment manufacturing or refurbishment 

category consists of processes that manufacture or refurbish 

gas-insulated substations, circuit breakers, other switchgear, 

gas-insulated lines, or power transformers (including gascontaining components of such equipment) containing sulfurhexafluoride (SF6) or perfluorocarbons (PFCs). The processes 

include equipment testing, installation, manufacturing, 

decommissioning and disposal, refurbishing, and storage in gas 

cylinders and other containers.

§ 98.451 Reporting threshold.

You must report GHG emissions under this subpart if your 

facility contains an electrical equipment manufacturing or 

refurbishing process and the facility meets the requirements of 

§98.2(a)(1). Electrical equipment manufacturing and refurbishing 

facilities covered by this rule are those that have total annual 

purchases of SF6 and PFCs that exceed 23,000 pounds.

§ 98.452 GHGs to report.

(a) You must report SF6 and PFC emissions at the facility 

level. Annual emissions from the facility must include SF6 and 

PFC emissions from equipment that is installed at an off-site 

electric power transmission or distribution location whenever 

emissions from installation activities (e.g., filling) occur 
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before the title to the equipment is transferred to the electric 

power transmission or distribution entity.

(b) You must report CO2, N2O and CH4emissions from each 

stationary combustion unit. You must calculate and report these 

emissions under subpart C of this part (General Stationary Fuel 

Combustion Sources) by following the requirements of subpart C 

of this part.

§ 98.453 Calculating GHG emissions.

(a) For each electrical equipment manufacturer or 

refurbisher, estimate the annual SF6 and PFC emissions using the 

mass-balance approach in Equation SS–1 of this section:

where:

Decrease in SF6 Inventory = (Pounds of SF6 stored in containers 

at the beginning of the year)—

(Pounds of SF6 stored in containers 

at the end of the year).

Acquisitions of SF6 = (Pounds of SF6 purchased from 

chemical producers or suppliers in 

bulk) + (Pounds of SF6 returned by 

equipment users) + (Pounds of SF6

returned to site after off-site 

recycling).

Disbursements of SF6 = (Pounds of SF6 contained in new 

equipment delivered to customers) + 

(Pounds of SF6 delivered to equipment 

users in containers) + (Pounds of SF6

returned to suppliers) + (Pounds of 

SF6 sent off site for recycling) + 

(Pounds of SF6 sent off-site for 

destruction).
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(b) Use the mass-balance method in paragraph (a) of this 

section to estimate emissions of PFCs associated with the 

manufacture or refurbishment of power transformers, substituting 

the relevant PFC(s) for SF6 in Equation SS–1 of this section.

(c) Estimate the disbursements of SF6 or PFCs sent to 

customers in new equipment or cylinders or sent off-site for 

other purposes including for recycling, for destruction or to be 

returned to suppliers using Equation SS–2 of this section:

Where:

DGHG = The annual disbursement of SF6 or PFCs sent to 

customers in new equipment or cylinders or sent offsite for other purposes including for recycling, for 

destruction or to be returned to suppliers.

Qp = The mass of the SF6 or PFCs charged into equipment or 

containers over the period p sent to customers or 

sent off-site for other purposes including for 

recycling, for destruction or to be returned to 

suppliers.

n = The number of periods in the year.

(d) Estimate the mass of SF6 or PFCs disbursed to customers 

in new equipment or cylinders over the period p by monitoring 

the mass flow of the SF6 or PFCs into the new equipment or 

cylinders using a flowmeter, or by weighing containers before 

and after gas from containers is used to fill equipment or 

cylinders, or by using the nameplate capacity of the equipment.
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(e) If the mass of SF6 or the PFC disbursed to customers in 

new equipment or cylinders over the period p is estimated by 

weighing containers before and after gas from containers is used 

to fill equipment or cylinders, estimate this quantity using 

Equation SS–3 of this section:

Where:

Qp = The mass of SF6or the PFC charged into equipment 

or containers over the period p sent to customers 

or sent off-site for other purposes including for 

recycling, for destruction or to be returned to 

suppliers.

MB = The mass of the contents of the containers used 

to fill equipment or cylinders at the beginning 

of period p.

ME = The mass of the contents of the containers used 

to fill equipment or cylinders at the end of 

period p.

EL = The mass of SF6or the PFC emitted during the 

period p downstream of the containers used to 

fill equipment or cylinders and in cases where a 

flowmeter is used, downstream of the flowmeter

during the period p (e.g., emissions from hoses 

or other flow lines that connect the container to 

the equipment or cylinder that is being filled).

(f) If the mass of SF6 or the PFC disbursed to customers in 

new equipment or cylinders over the period p is determined using 

a flowmeter, estimate this quantity using Equation SS–4 of this 

section:

Where:
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Qp = The mass of SF6or the PFC charged into equipment 

or containers over the period p sent to customers 

or sent off-site for other purposes including for 

recycling, for destruction or to be returned to 

suppliers.

Mmr = The mass of the SF6or the PFC that has flowed 

through the flowmeter during the period p.

EL = The mass of SF6or the PFC emitted during the 

period p downstream of the containers used to 

fill equipment or cylinders and in cases where a 

flowmeter is used, downstream of the flowmeter 

during the period p (e.g., emissions from hoses 

or other flow lines that connect the container to 

the equipment that is being filled).

(g) Estimate the mass of SF6 or the PFC emitted during the 

period p downstream of the containers used to fill equipment or 

cylinders (e.g., emissions from hoses or other flow lines that 

connect the container to the equipment or cylinder that is being 

filled) using Equation SS–5 of this section:

Where:

EL = The mass of SF6 or the PFC emitted during the period 

p downstream of the containers used to fill 

equipment or cylinders and in cases where a 

flowmeter is used, downstream of the flowmeter 

during the period p (e.g., emissions from hoses or 

other flow lines that connect the container to the 

equipment or cylinder that is being filled)

FCi = The total number of fill operations over the period 

p for the valve-hose combination Ci.

EFCi = The emission factor for the valve-hose combination 

Ci.

n = The number of different valve-hose combinations C 

used during the period p.
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(h) If the mass of SF6 or the PFC disbursed to customers in 

new equipment or cylinders over the period p is determined by 

using the nameplate capacity, or by using the nameplate capacity 

of the equipment and calculating the partial shipping charge, 

use the methods in either paragraph (h)(1) or (h)(2) of this 

section.

(1) Determine the equipment's actual nameplate capacity, by 

measuring the nameplate capacities of a representative sample of 

each make and model and calculating the mean value for each make 

and model as specified at §98.454(f).

(2) If equipment is shipped with a partial charge, 

calculate the partial shipping charge by multiplying the 

nameplate capacity of the equipment by the ratio of the 

densities of the partial charge to the full charge.

(i) Estimate the annual SF6and PFC emissions from the 

equipment that is installed at an off-site electric power 

transmission or distribution location before the title to the 

equipment is transferred by using Equation SS–6 of this section:

Where:

EI = Total annual SF6 or PFC emissions from 

equipment installation at electric 

transmission or distribution facilities.
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MF = The total annual mass of the SF6 or PFCs, in 

pounds, used to fill equipment during 

equipment installation at electric 

transmission or distribution facilities.

MC = The total annual mass of the SF6or PFCs, in 

pounds, used to charge the equipment prior to

leaving the electrical equipment manufacturer 

facility.

NI = The total annual nameplate capacity of the 

equipment, in pounds, installed at electric 

transmission or distribution facilities.

§ 98.454 Monitoring and QA/QC requirements.

(a) For calendar year 2011 monitoring, you may follow the 

provisions of §98.3(d)(1) through (d)(2) for best available 

monitoring methods rather than follow the monitoring 

requirements of this section. For purposes of this subpart, any 

reference in §98.3(d)(1) through (d)(2) to 2010 means 2011, 

March 31 means June 30, and April 1 means July 1. Any reference 

to the effective date in §98.3(d)(1) through (d)(2) means 

February 28, 2011.

(b) Ensure that all the quantities required by the 

equations of this subpart have been measured using either 

flowmeters with an accuracy and precision of ±1 percent of full 

scale or better or scales with an accuracy and precision of ±1 

percent of the filled weight (gas plus tare) of the containers 

of SF6 or PFCs that are typically weighed on the scale. For 

scales that are generally used to weigh cylinders containing 115 

pounds of gas when full, this equates to ±1 percent of the sum 
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of 115 pounds and approximately 120 pounds tare, or slightly 

more than ±2 pounds. Account for the tare weights of the 

containers. You may accept gas masses or weights provided by the 

gas supplier e.g., for the contents of cylinders containing new 

gas or for the heels remaining in cylinders returned to the gas 

supplier) if the supplier provides documentation verifying that 

accuracy standards are met; however, you remain responsible for 

the accuracy of these masses and weights under this subpart.

(c) All flow meters, weigh scales, and combinations of 

volumetric and density measures that are used to measure or 

calculate quantities under this subpart must be calibrated using 

calibration procedures specified by the flowmeter, scale, 

volumetric or density measure equipment manufacturer. 

Calibration must be performed prior to the first reporting year. 

After the initial calibration, recalibration must be performed 

at the minimum frequency specified by the manufacturer.

(d) For purposes of Equations SS–5 of this subpart, the 

emission factor for the valve-hose combination (EFC) must be 

estimated using measurements and/or engineering assessments or 

calculations based on chemical engineering principles or 

physical or chemical laws or properties. Such assessments or 

calculations may be based on, as applicable, the internal volume 

of hose or line that is open to the atmosphere during coupling 

and decoupling activities, the internal pressure of the hose or 
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line, the time the hose or line is open to the atmosphere during 

coupling and decoupling activities, the frequency with which the 

hose or line is purged and the flow rate during purges. You must 

develop a value for EFc(or use an industry-developed value) for 

each combination of hose and valve fitting, to use in Equation 

SS–5 of this subpart. The value for EFCmust be determined for 

each combination of hose and valve fitting of a given diameter 

or size. The calculation must be recalculated annually to 

account for changes to the specifications of the valves or hoses 

that may occur throughout the year.

(e) Electrical equipment manufacturers and refurbishers 

must account for SF6 or PFC emissions that occur as a result of 

unexpected events or accidental losses, such as a malfunctioning 

hose or leak in the flow line, during the filling of equipment 

or containers for disbursement by including these losses in the 

estimated mass of SF6 or the PFC emitted downstream of the 

container or flowmeter during the period p.

(f) If the mass of SF6 or the PFC disbursed to customers in 

new equipment over the period p is determined by assuming that 

it is equal to the equipment's nameplate capacity or, in cases 

where equipment is shipped with a partial charge, equal to its 

partial shipping charge, equipment samples for conducting the 

nameplate capacity tests must be selected using the following 

stratified sampling strategy in this paragraph. For each make 
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and model, group the measurement conditions to reflect 

predictable variability in the facility's filling practices and 

conditions (e.g., temperatures at which equipment is filled). 

Then, independently select equipment samples at random from each 

make and model under each group of conditions. To account for 

variability, a certain number of these measurements must be 

performed to develop a robust and representative average 

nameplate capacity (or shipping charge) for each make, model, 

and group of conditions. A Student T distribution calculation 

should be conducted to determine how many samples are needed for 

each make, model, and group of conditions as a function of the 

relative standard deviation of the sample measurements. To 

determine a sufficiently precise estimate of the nameplate 

capacity, the number of measurements required must be calculated 

to achieve a precision of one percent of the true mean, using a 

95 percent confidence interval. To estimate the nameplate 

capacity for a given make and model, you must use the lowest 

mean value among the different groups of conditions, or provide 

justification for the use of a different mean value for the 

group of conditions that represents the typical practices and 

conditions for that make and model. Measurements can be 

conducted using SF6, another gas, or a liquid. Re-measurement of 

nameplate capacities should be conducted every five years to 
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reflect cumulative changes in manufacturing methods and 

conditions over time.

(g) Ensure the following QA/QC methods are employed 

throughout the year:

(1) Procedures are in place and followed to track and weigh 

all cylinders or other containers at the beginning and end of 

the year.

(h) You must adhere to the following QA/QC methods for 

reviewing the completeness and accuracy of reporting:

(1) Review inputs to Equation SS–1 of this subpart to 

ensure inputs and outputs to the company's system are included.

(2) Do not enter negative inputs and confirm that negative 

emissions are not calculated. However, the decrease in SF6

inventory may be calculated as negative.

(3) Ensure that beginning-of-year inventory matches end-ofyear inventory from the previous year.

(4) Ensure that in addition to SF6 purchased from bulk gas 

distributors, SF6 returned from equipment users with or inside 

equipment and SF6 returned from off-site recycling are also 

accounted for among the total additions.

§ 98.455 Procedures for estimating missing data.

A complete record of all measured parameters used in the 

GHG emissions calculations is required. Replace missing data, if 

needed, based on data from similar manufacturing operations, and 
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from similar equipment testing and decommissioning activities 

for which data are available.

§ 98.456 Data reporting requirements.

In addition to the information required by §98.3(c), each 

annual report must contain the following information for each 

chemical at the facility level:

(a) Pounds of SF6 and PFCs stored in containers at the 

beginning of the year.

(b) Pounds of SF6 and PFCs stored in containers at the end 

of the year.

(c) Pounds of SF6 and PFCs purchased in bulk.

(d) Pounds of SF6 and PFCs returned by equipment users with 

or inside equipment.

(e) Pounds of SF6 and PFCs returned to site from off site 

after recycling.

(f) Pounds of SF6 and PFCs inside new equipment delivered to 

customers.

(g) Pounds of SF6 and PFCs delivered to equipment users in 

containers.

(h) Pounds of SF6 and PFCs returned to suppliers.

(i) Pounds of SF6 and PFCs sent off site for destruction.

(j) Pounds of SF6and PFCs sent off site to be recycled.
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(k) The nameplate capacity of the equipment, in pounds, 

delivered to customers with SF6 or PFCs inside, if different from 

the quantity in paragraph (f) of this section.

(l) A description of the engineering methods and 

calculations used to determine emissions from hoses or other 

flow lines that connect the container to the equipment that is 

being filled.

(m) The values for EFCi of Equation SS-5 of this subpart for

each hose and valve combination and the associated valve fitting 

sizes and hose diameters.

(n) The total number of fill operations for each hose and 

valve combination, or, FCi of Equation SS–5 of this subpart.

(o) If the mass of SF6 or the PFC disbursed to customers in 

new equipment over the period p is determined according to the 

methods required in §98.453(h), report the mean value of

nameplate capacity in pounds for each make, model, and group of 

conditions. 

(p) If the mass of SF6 or the PFC disbursed to customers in 

new equipment over the period p is determined according to the 

methods required in §98.453(h), report the number of samples and 

the upper and lower bounds on the 95 percent confidence interval 

for each make, model, and group of conditions.
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(q) Pounds of SF6 and PFCs used to fill equipment at offsite electric power transmission or distribution locations, or 

MF, of Equation SS–6 of this subpart.

(r) Pounds of SF6and PFCs used to charge the equipment prior 

to leaving the electrical equipment manufacturer or 

refurbishment facility, or MC, of Equation SS–6 of this subpart.

(s) The nameplate capacity of the equipment, in pounds, 

installed at off-site electric power transmission or 

distribution locations used to determine emissions from 

installation, or NI, of Equation SS–6 of this subpart.

(t) For any missing data, you must report the reason the 

data were missing, the parameters for which the data were 

missing, the substitute parameters used to estimate emissions in 

their absence, and the quantity of emissions thereby estimated.

§ 98.457 Records that must be retained.

In addition to the information required by §98.3(g), you 

must retain the following records:

(a) All information reported and listed in §98.456.

(b) Accuracy certifications and calibration records for all 

scales and monitoring equipment, including the method or 

manufacturer's specification used for calibration.

(c) Certifications of the quantity of gas, in pounds, 

charged into equipment at the electrical equipment manufacturer 
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or refurbishment facility as well as the actual quantity of gas, 

in pounds, charged into equipment at installation.

(d) Check-out and weigh-in sheets and procedures for 

cylinders.

(e) Residual gas amounts, in pounds, in cylinders sent back 

to suppliers.

(f) Invoices for gas purchases and sales.

(g) GHG Monitoring Plans, as described in §98.3(g)(5), must 

be completed by April 1, 2011.

§ 98.458 Definitions.

All terms used in this subpart have the same meaning given 

in the CAA and subpart A of this part.