ML20086K043

Comment on Draft Reg Guide DG-8003 & NUREG-1400, Air Sampling in Workplace. Licensee Feels That Concept Could Be Useful Tool in Determining When Air Sampling Is Warranted But Feels Hazard Index Level Needs Clarification

ML20086K043
Person / Time
Site:	Duane Arnold
Issue date:	12/02/1991
From:	Giorgio H IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT
To:	NRC OFFICE OF ADMINISTRATION (ADM)
References
FRN-56FR52078, RTR-NUREG-1400, RTR-REGGD-08.025, RTR-REGGD-8.025, RULE-PR-MISC, TASK-DG-8003, TASK-RE 56FR52078-00006, 56FR52078-6, NUDOCS 9112120185
Download: ML20086K043 (3)

Text

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[g cj G fd'iM7T lowa Electric Light and Power Conitun3 December 2, 1991 RIGUt ley,$ M h3g 7

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Chief 91 DEC -9 A;j :15 Regulatory Publications Branch

< US NRC Washington, DC 20555 RE: Duane Arnold Energy Center

SUBJECT:

Comments on DrafL Regulat.ory Guide DG-0003 and 140 REG 1400 " Air Sampling in the Workplace" FILE: A-106, NRC-10 5

In general, this regulatory guido seems to be geared toward facilities using air sampling as a dose assessment tool and not t.hos e facilities utilizing air sampling as a survey tool and whole body counting as an assessment. tool. Consequently, it is not very useful t.o such facilities (i.e., nuclear power plant.s),

and could place undue requirements upon their programs with no benefit. Of particular concern is the requirement to observe airflow patterns. This is not. feasible at facti 1 Lies where t.he work location changes daisy.

The concept of llazard I.ndex present.ed in the Reg. Guido and expanded upon in the NUREG could be a useful tool in determining when air sampling is warrant.ed, even at nuclear power plants.

Ilowever, there should be a clear Hazard Index level below which air sampling is not warranted. A llazard Index of 1 is an appropriate dominimus value.

Several sections of the Reg. Guido appear to be bet.ter suited for ANSI Standards: 3.5 Efficiency of Collect. ion Media, 3.6 Lower Limit of Detectors, 3.7 Adjusting DACs for Particle Size, 4.7

% Periodic Operational Checks, 4.8 Calibration of Continuous Air Monitors, and 5.0 Measurement of the Volume of Air sampled.

Finally, specific items of concern for the Reg. Guide and NUREG are provided as an att.achment to this letter.

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Certified Health Physicist HG/hc Attachments Duar ? Arnola Lnery Crnier

• 3277 UALC Road

• l'alo, luna 52324

• 319 831 7611 9112120105 911202 PDR HUGCD ,

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COMMENTS ON DRAFT PEGULATORY GUIDE DG-8003 &

NUREG 1400 BOTH TITLED AIR SAMPLING IN THE WORKPLACE It appcars three different parameters can be utilized to determine the recommended air sampling: Hazard Index, Intake, and/or Airborne concentrations. NUREG 1400 equation 1.3, which estimates intake, is  ;

identical to Reg. Guide 8.25's equation for Hazard Index. This is very confusing and needs to be corrected. I believe NUREG's equation 1.2 is what the author wants us to use when estimating intake while 1.3 should be utilized for determining a Hazard Index.

The modifying factor F in NUREG equation should not be set at 50 for short term tasks. It should remain 1. Tne base assumption in equation 1 1 of the NUREG assumes 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> exposure to the unoncapsulated material. A shorter exposure period will in effect reduce the intake. In determining whether or not sampling is appropriate, however, this smaller intake value is offset by a desire to pro-rate the ALI to an equivalent length of time. The two effects ,

are inversely proportional to each other, resulting in no change in the equation for Hazard Index.

To illustrate the point consider the following. The HI assigned to a one time walkdown of a system in a highly contaminated room is 50 ,

times higher than that assigned to the repetitive task of making daily ontries to check on equipment. This does not seem-logical.

Table 1.2 of NUREG 1400 implies Brodsky's observations were based on work in a well ventilated hood. If this is not true, then these factors need to be adjusted. Additionally, the term hood needs to be

. clearly defined. A hood could mean an enclosure or receiving hood or a Capturing hood. Each of these could have different confinement factors.

Table 1 in the Reg. Guido provides reasonable choices except it has no lower value below which the hazard is diminimus, warranting no air sampling. A value of 1-seems to_be: appropriate for this, for if an individual works in an area with a Hazard Index of one, the monthly committed effective dose equivalent not accounted for is less than 5 millirem.

The Reg. Guide can be read to require routine sampling, air flow

observations, etc., even if the Hazard Index is well below 1. This l_

stance-is further enhanced by example 1.4 in NUREG 1400, where air

-sampling was recommended for an I value of 0.05_and an HI value of 0.0026. _This will force _ licenses to perform unnecessary tasks, increasing cost and dose for no apparent gain.

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There seems-to be'no provision in the Reg. Guide to utilize air sampling as a survey tool when a bicassay program is used for_ dose assessment.

There is a typo in equation 1.13 of NUREG 1400. The value for 0, in equation 1.10, was changed from 2.4x10" C1 to 2.4x10" C1.

The conclusions reached in example 1.4 vs 1.5 of NUREG 1400 are contradictory. The former results_in a calculated I value ofH0.05_and an HI value of 0.0026 with the conclusion: air sampling is warranted,

-while the latter results in an HI of 0.8 with a conclusion sampling i

i may not be warranted. Both conclusions fly in the face of the values presented in Table 1.3 of the NUREG (or Table 1 of the Reg. Guide).

Section 3.5 in NUREG 1400 implies there is no lower limit for monitoring and assessing internal dose if a transient worker arrives at a facility with 10% of an ALI. Such a philosophy means we should ,

throw out Table 1.3 and could jeopardize the employability of workers l with-internal uptakes in excess of 10% of an ALI.

Pro-rating the requirements seems like a much more logical way to do business. If a worker could receive, in a week, 0.002 ALI (i.e., the sum of all HIs for the week equals 10), than perform an assessment and assign the doso. If the person does not exceed this value in any one week, no assessment is necessary nor is any dose assigned, even if he/she arrived at the site with 10% of an ALI.

Using equation 1.2 in example 1.4 of the NUREG to determine Intake as l

% of ALI is not appropriate. This equation assumes the worker handles i the unencapsulated material for 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br />. <

It-should be made clear, in both documents, that the licensee should calculate intake _(I) for continuous tasks and Hazard Index (HI) for short duration tasks-(% DAEC could be used in either case). -As l currently written, and as implied in example 1.4, the documents can be interpreted as requiring the determination of all three parameters, then using the most conservative value in the decision making value.

Evaluation.of the need for_ air sampling 1c based on handling 10,000 times the ALI in a year. This is not clear if this means handling the same repeatedly or repeatedly handling new material. Which of the following activities qualifies:

1) Entering a room contaminated with 10 ALIs worth of material 4 times a day.

2)^ Entering, once, a large room contaminated with 10,000 ALIs worth of material

3) Entering, once, a small room contaminatnd with 10,000 ALIs worth of material?

4) Handling the same 10 ALI un-encapsulated source 4 times a day every day?

5) Handling a different 10 ALI un-encapsulated source 4 times a day every_ day.

The examples in the NUREG imply that 2, 3, and 4 meet this 10,000 ALI trigger, while 1 and~3 do not.

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