DRAFT WORK PRACTICE STANDARDS

FOR HF AND HCI EMISSIONS FROM WOOL FIBERGLASS MELTING FURNACES
In 2010 and 2012, emissions testing atwool fiberglass facilities was conducted for all HAP believed to be emitted from wool fiberglass glass meltingfurnaces. The results of measurements for the acid gases HF and HCI were returned belowthe test method detection limits in 80% ofthe HCI measurements and over 85% ofthe HF measurements, including measurements atfacilities that add small amounts offluorides to the glass formulation. Where these Haps were measured at detectable levels in the furnace emissions, they were measured at very low levels. We therefore proposed (78 Fed. Reg

. at 22370) to require work practice standards forthe acid gases HF and HCI from furnaces at major sources, and are promulgating such standards forthese pollutants in the final rule. Emissions ofthe acid gases HF and HCI can originate from the chloride and fluoride contained in the raw materials used for glass formulations. Refined raw batch materials such as sand and purchased cullet may contain trace amounts ofchlorides, which in much higher concentrations are undesirable in a wool fiberglass furnace environment

. Chlorides can readily form HCI, and significant levels ofchlorides can damage furnaces. Fluorine can enterthe purchased cullet stream as a component ofglass from cathode-ray tubes (CRTs) orcomputer monitors that include cathode ray tubes. Fluoride emissions can occur when CRT glass entersthe purchased cullet stream from the recycling center. Wool fiberglass facilities can monitor chloride content ofthe cullet orfinished glass to verify and to maintain insignificanttrace levels ofchlorides. This is done by standard chemical analytic techniques. Wool fiberglass facilities monitortheir purchased cullet to ensure that it does not contain excessive fluoride-bearing CRT glass

.The facility typically requires the providers ofpurchased culletto verifythat the cullet does not contain glass from such sources. Facilities can also test the fluoride content ofthefinished glass. Wool fiberglass manufacturingfacilities subjectto NNN shall comply with one ofthe following alternativework practices for HCI:

• An alternative work practice for HCI: Facilities subject to NNN are requ ired to use a feedstock of raw materials having a 12 month rolling average ofchloride content at or below 0

.1 percent as measured using methods similarto ASTM 1152C/1152M, "Standard Test Method for Acid-Soluble Chloride in Mortar and Concrete," or companydeveloped methods using wavelength-dispersive x-ray fluorescence, or ion electrode analysis, ion chromatography, or using other standard laboratory methods.• An alternative work practice for HCI: Facilities subject to NNN will maintain glass formulation records thatshowthat no ingredient containing intentionally added chloride will be added tothe batch used to produce wool fiberglass insulation

. Manufacturers will maintain records for 5 years and such records may be inspected by 

### EPA.

• An alternative work practice for HCI: Facilities subject to NNN will measure HCI emissions during emission testing once every 5 years to confirm thatthe level of HCI emissions is similarto the industry levels measured duringthe rulemaking process.

• An alternative work practice for HCI: Facilities subject to NNN will generate a baseline set ofdata (i.e., 2 years ofdata- minimum of8 samples, existing or new- raw materials orfinished glass) and establish the mean and standard deviation. Ifthe manufacturer maintains levels that are less than the mean plus two standard deviations, no further action is required

. lfthe analytical results rise above two standard deviations above the baseline, the manufacturer musttake action to assess and documentthe impact on HCI emissions. Action could include stack testing to verify HCI emissions are within <+25% {1.25 X) ofthe originaiiCR results, investigation ofraw material ch loride content, verification ofanalytical results, new raw material supplier, etc. Actions must be documented and maintained for a minimum of5 years. Wool fiberglass manufacturing facilities subject to NNN shall comply with one ofthe following alternativework practices for HF:

• An alternative work practice for HF: Facilities subjectto NNN must maintain records from their own sampling program, orobtain annual certification from cullet providers verifying thatthe cullet does not contain excessive CRT glass.

• An alternative work practice for HF: Facilities subject to NNN will measure HF emissions duringemission testing once every 5 years to confirm thatthe level of HF emissions is not more than the industry levels measured duringthe rulemaking process
. Facilities must maintain records ofthe selected work practices for a 5 year period for raw materials and/or records ofglass formulations indicatingthefacility is maintaining low HF and HCI emissions, and make these records available for inspection by the permitting authority upon demand. Failure to maintain such records would constitute a deviation from the requirement

.