ML13317A127
| ML13317A127 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/31/1982 |
| From: | WYLE LABORATORIES |
| To: | |
| Shared Package | |
| ML13317A128 | List: |
| References | |
| NUDOCS 8206020439 | |
| Download: ML13317A127 (29) | |
Text
ACOUSTICAL TEST OF PROMPT ALERTING SYSTEM FOR SAN ONOFRE NUCLEAR GENERATING STATION (Test Date: 24 May 1982)
Prepared for SOUTHERN CALIFORNIA EDISON COMPANY Rosemead, California 91770 Prepared by WYLE RESEARCH El Segundo, California 90245 (J/N 39145)
MAY 1982 6206020439 620528 PDR ADOCK 05000206 F
TABLE OF CONTENTS Page
1.0 INTRODUCTION
1-1 2.0 TEST PROCEDURES.......
2-1 2.1 Siren System Activation................
2-1 2.2 Sound Measurement Locations.............
2-1 2.3 Sound Measurement Procedures............. 2-13 3.0 TEST RESULTS.................
3-1 3.1 Typical Siren Signal Characteristics....
3-1 3.2 Summary of Measured Test Data......
3-2 3.3 Review of Test Results.........
3-9 WYLE LABORATORIES
1.0 NTRODUCTION A prompt alerting system consisting of 40 sirens has been installed within the 10-mile Emergency Planning Zone (EPZ) of the San Onofre Nuclear Generating Station (SONGS).
The system is deployed throughout community, beach front, military, and commercial areas in parts of Orange and San Diego Counties.
Control and activation of the system is retained by five agencies; namely:
o Orange County (OC) o San Juan Capistrano (SJ) o San Clemente (SC) o State Parks (SP) o Camp Pendleton (CP)
Locations of the 40 sirens throughout the 10-mile EPZ are illustrated in Figures IA and I B. Sirens within each control zone are prefixed with the letter codes shown above.
A test to determine performance of the system was conducted on May 24, I982, during which all sirens were simultaneously activated and set to operate for a period of 4 minutes.
During this test, sound level data comprising ambient background noise levels (pretest and post-test) and siren signal levels, were measured at 28 sites within the 10-mile EPZ.
These include a previously installed siren owned by the City of San Clemente.
WYLE LABORATORIES
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2.0 TEST PROCEDURES 2.1 Siren System Activation The siren system activation and test was scheduled to commence at 1415 hours0.0164 days <br />0.393 hours <br />0.00234 weeks <br />5.384075e-4 months <br /> on 24 May 1982.
Each controlling agency was to activate its respective sirens after confirmation of readiness by al other agencies.
In practice, the system was activated at 1418 hours0.0164 days <br />0.394 hours <br />0.00234 weeks <br />5.39549e-4 months <br /> on the test day. Timer controls of each siren were preset to provide a siren operation period of 4 minutes.
The following is a summary of siren deviations from the scheduled performance:
Sirens not activated:
OC07, OC08, SC04, CPO8.
Sirens with foreshortened periods of activation:
CPO3.
Sirens with protracted periods of activation:
SJO I, SCO I, SCO3, SCO6, OC04.
All other 30 sirens operated in accordance with the scheduled performance.
2.2 Sound Measurement Locations Twenty-nine sound measurement locations were used in the May 24, 1982, test.
These 29 locations comprised the main body of sites at which deficiencies of signal level or signal-to-(ambient) noise were noted in a previous test of the system during January 25 to 29, 1982.
The measurement sites were identical to those previously used, which were part of a randomly selected sample of 81 sites covering all control zones and agencies.
Figures 2(a) through 2(i) show the 29 sound measurement locations (high lighted) in relation to the siren locations. Table I contains a brief description of each sound measurement location, as employed by the respective measurement teams to identify sites.
In each reference to site locations, the following prefixes have been used to relate the sites to the respective zones (agencies):
Instrumentation failure at one site reduced the number of sites with data to 28.
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Table I COMMUNITY SIREN SYSTEM 5/24/82 TEST Measurement Location Descriptions by Team Team I D2 On bluff midway between SONGS southeast corner and State Parks entrance booth D3 Southeast corner of SONGS property on State Parks Rd., approx. 1,500 ft north of SP02 D8 Midway between SP04 and SP05 on State Parks Rd.
D9x 0.5 miles southeast of SP05 on State Parks Rd.
DIOx 1.0 miles southeast of SPOS on State Parks Rd.
Team 2 AlOx At far west hairpin curve of Via Verde in Louise Leydon Park B8 Corner of Camino Capistrano and Via Serra Bl4x 100 ft south of freeway underpass around 33900 Camino Capistrano BlOx On sidewalk by Golf Clubhouse on San Juan Creek Rd.
BI lx By large tree on first curve of Forster Ranch Rd. just off Valle Rd.
Team 3 A3 Mid-block on Via Lopez, between Via California and Via Sacramento C2 At 3925 Via Manzana just off Calle Bienvenido A9x N. side of Calle Portola, 125 ft west of Calle Juanita A4 Vacant lot on S. side of Calle Naranja, third lot NW of Calle Toba Team 4 B6 NW corner of Via Cascada and Paseo de DeCora B7 NE corner of Calle Borrego and Via Banderas Al2x At bend between Calle Real and Paloma (in 34600 block of Paloma)
C4 At 842 Camino de Los Mares almost to Calle Nuevo Team 5 C14 At 315 Calle Neblina - between Calle Miguel and Avenida Presidio C12 100 ft south of cul-de-sac (at #425) on Calle Delicade C16 Corner of Avenida la Esperanza and Avenida Buena Suerte C20 At end of cul-de-sac (#115) Avenida Verde C21 Corner of Avenida Acapulco and Via Cisco 2-11
Table I (Continued)
Team 6 C18 425 ft northwest of Linda Lane beach parking - beach side of railroad track SP On Ave Cabrillo between Palizada and Ole Vista C22 At end of cul-de-sac on Trafalgar Court El I 1
.0 miles west of CP08 DI 3,200 ft north of SPOI on Basilone Road Team 7 B5 Mid-block (#137) Caoba St B13 Southernmost point of Forster Ranch Rd., where road turns northward into residential area 2-12
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A Orange County B
San Juan Capistrano C
San Clemente D
State Parks E
Camp Pendleton 2.3 Sound Measurement Procedures Instrumentation Precision Sound Level Meters complying with American National Standard ANSI SI.4-1971 (R1976), "Specifications for Type I Sound Level Meters," were employed at all sites for the measurement of ambient (background) noise levels and siren signal levels.
In addition, these sound level meters were supplemented at selected sites by analog tape recording systems which comply with the require ments of ANSI S6.1-1973, "Qualifying a Sound Data Acquisition System."
Each item or system of measurement.equipment was calibrated in accordance with the manufacturer's specifications. Field calibrations were performed prior to and after each test sequence by means of an acoustic calibrator.
All analog recordings of sound pressure were preceded by an acoustic calibration signal identical to that used for field calibration of measurement equipment.
Personnel and Briefings The acoustical measurements were performed by 29 engineering personnel.
These personnel were distributed into seven teams, each of which was supervised by an engineer who was highly experienced in the acquisition of sound level data and who had detailed knowledge of the survey area and measurement sites.
Formal briefings and training sessions were held between 9 a.m. and 11:30 a.m. on May 24, 1982, to ensure that personnel were fully familiar with the requirements of the sound level data acquisition process using the particular type of instrumentation allocated to them. Dispersal to measurement sites commenced at 12:45 p.m. on the test day and all personnel were in place prior to siren activation.
Data Acquisition Table 2 is a replica of "measurement procedures and test log section" sheets issued to each sound measurement engineer. Separate instruction sheets on system 2-13 WYLE LABORATORIES
operation, calibration procedures, and site locations were also issued to engineers as part of a Log Book. Each log book, together with instrumentation used in the survey, was inspected and/or tested for completeness and conformation with procedures at a debriefing session after the test.
The data acquisition procedures comprised four tasks, as follows:
Calibration:
Each measurement system was calibrated at the measurement site by means of an acoustic calibrator.
Pretest Ambient Noise Measurement:
A measurement was obtained of the typical ambient (background) noise level at the measurement site prior to siren activation. This measurement was performed to acquire information on the typical value of L, the sound level exceeded during 90 percent of the measurement time period.
Siren Signal Measurement: During the activation period of the siren, sound level data were acquired which provided information on the maximum and minimum sound levels (at the site) which were directly attributable to the siren signal. To minimize interference by wind noise, the siren levels were measured in terms of A-weighted levels, and subsequently corrected to C weighted levels for this report.
Post-Test Ambient Noise Measurement:
The procedure for measuring ambient (background) noise at the site was repeated after all siren signals were known to have ceased.
2-14 WYLE LABORATORIES
Table 2 COMMUNITY SIREN, 5/24/82 TEST Measurement Procedures I.
Calibrate microphones and record calibration data (at direction of Team Leader)
- 2.
Arrive at site and verify correct location
- 3.
Annotate tape (if using a recorder) and continue Log Section fill-in
- 4.
Set up sound level meters or microphones on tripods (if provided)
- 5.
Prepare for measurement
- 6.
Contact TSC and inform them of readiness (via Team Leader)
- 7.
Measure ambient noise while waiting for siren activation (2 p.m.)
- 8.
Take siren data followed by post-test ambient noise reading
- 9.
Complete Log Section entries including any informational notes
- 10.
Wait for Team Leader pick-up I1.
Pack equipment into vehicle
- 12.
Return to Marina Inn for equipment turn-in and debriefing COMMUNITY SIREN 5/24/82 TEST LOG SECTION Sound Level Meter Data Test Engr:
Date:
Sound Level Meter Type/Model #:
Set SLM to "Slow" response Serial #:
Set SLM to "A" weighting Calibrator Type/Model/Serial #:
/
/
dB at kHz TEST #1 Location #:
Time:
Battery OK?
Location
==
Description:==
MEASURED SOUND LEVELS Ambient Ambient (pre-test)
Siren Sound Level (post-test)
Min Max Comments:
2-15
3.0 TEST RESULTS 3.1 Typical Siren Signal Characteristics Figures 3 and 4 show one-third octave band frequency spectra for short-term samples of the siren signals recorded at Locations A4 and C2 1, respectively. These spectra illustrate that the primary frequency content of the siren signals was in the 315 Hz and 400 Hz one-third octave bands, with minor harmonic levels at higher frequencies, and that the siren signals at these two locations were well in excess of noise levels in adjacent frequency bands.
Tables 3 and 4 show the statistical characteristics of the ambient noise and siren test signals at each of the two locations (A4 and C21).
For Location A4, Table 3(a) shows the ambient noise statistics and Table 3(b) shows the siren signal data. Similarly, for Location C21, Table 4(a) shows the ambient noise character istics and Table 4(b) shows the siren signal characteristics. In each of these tables, the Lo, L 1, L 10, etc., values are the sound pressure levels exceeded for 0 percent, I percent, 10 percent, etc., of the sample time period. These values are shown to be evaluated for each one-third octave band, for the overall A-weighted Sound Level, and for the overall Sound Pressure Level (Linear).
Examination of these tables shows that the siren signal levels at these two locations were well in excess of ambient background noise levels in the octave band containing the siren signal. (It should be noted that these short-term samples were extracted from the full record of the test. They are representative of, but do not necessarily agree exactly with, the test data submitted by the engineers for the complete test period.)
3.2 Summcry of Measured Test Data Table 5 is a compilation of all acoustic data acquired during the May 24, 1982, siren system test. Evaluation of the relationship between the Sound Level Meter data and the statistical values of (a) LIO, dB, for the siren signal level, and (b) the ambient noise level, L90, dB, in the octave. band containing the siren signal frequency, indicated that no corrections needed to be applied to the measured sound levels in compiling the Table 5 summary.
These metrics, 10 and L90, are recognized indices of signal intrusiveness and ambient background noise level, respectively.
These are consistent with research supporting FEMA Report CPG-1-17, "Outdoor Warning Systems Guide," as referred to in NUREG-0654.
3 WYLE LABORATORIES
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Figure 3.
One-Third Octave Band Spectrum of Siren Signal Measured at Location A4 (24 May 1982)
WYLE LABORATORIES 3-2
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One-Third Octave Band Spectrum of Siren Signal Measured at Location C21 (24 May 1982) 3-3 WYLE LABORATORIES
Table 3(a)
Statistical Characteristics of Ambient Noise Recorded at Location A4 (24 May 1982)
ZONE LOCATION A4 TYPE (S OR A) A Leq L99 L90 L50 L10 Li LO Freq =
100 49.3 42.5 44.5 47.5 51.5 57.0 58.5 Freq =
125 43.9 39.0 40.0 42.5 46#0 49,5 50.0 Freq =
160 39.6 35.0 36.5 38.5 41.5 44.0 47.5 Freq =
200 39.1 33.0 35.0 38.0 41.0 45.0 45.5 Freq =
250 41.1 33.5 35.0 38.0 42.0 54.0 56.5 Freq =
315 41.3 35.5 36.5 39.0 43.5 51.0 53.5 Freq =
400 38.3 33.0 34.0 37.0 40.0 46.5 48.5 Freq =
500 38.5 34.0 '35,5 37.5 40.5 42.5 44.0 Freq =
630 38.7 34.5 36.0 38.0 40.5 42.5 43.0 Freq =
800 38.9 35.5 36.0 37,5 41.5 43.5 44.0 Freq =
1000 40.8 36.5 37.5 39.5 43.5 46.5 47.0 Freq =
1250 37.3 34.0 34.5 36.0 39.5 41.5 42.0 Freq =
1600 34.8 31.5 32.5 34.0 36.0 41.5 42.0 Freq =
2000 34.4 31.0 32.0 33.0 35.0 43.5 44.0 Freq =
2500 36.5 30.0 31.0 34.0 39.0 44.5 45.0 Freq =
3150 38.5 30.0 31.5 37.0 41.5 44.5 47.0 Freq =
4000 39.3 30.5 32.0 37.5 43.0 45,5 46.5 Freq =
5000 35.3 30.0 31.0 33.0 38.0 43,5 44.0 Freq =
6300 32.1 31.0 31.0 31.5 32.5 34.0 34.5 Freq =
8000 32.0 31.5 31.5 31.5 32,0 33.5 35.0 Freq = 10000 32.8 32.0 32.0 32.5 33.0 33.0 33.5
'A' Weighted 50.2 46.5 47.5 49.0 52.0.54.5 55.0 Linear 59.4 55.0 56.5 58.5 61.0 64.5 65.5 3-4 WYLE LABORATORIES
Table 3(b)
Statistical Characteristics of Sound Level Data Recorded at Location A4 During Siren Test (24 May 1982)
ZONE LOCATION A4 TYPE (S OR A) S Leq L99 L90 L50 L10 Li LO Freq =
100 52.1 45.0 46.0 48.5 55.5 61.0 62.0 Freq =
125 51.4 42.0 45.0 49.0 55.0 59.0 59.5 Freq =
160 60.4 48.0 50.5 59.0 64,0 68.5 69.0 Freq =
200 51.2 40.5 42.5 45.5 52.5 62.0 64.5 Freq =
250 47.3 40.5 41.5 45.5 50.0 53.0 54.0 Freq =
315 73.9 63.5 66.0 72.5 77.0 78.0 78.5 Freq =
400 72.8 62.0 64.5 71.5 76.0 77.0 77.5 Freq =
500 48.8 41.0 43.0 46.0 50.5 61.0 61.5 Freq =
630 60.6 45.5 49.5 57.0 64.5 71.0 71.5 Freq =
800 60.2 44.0 48.5 56.5 65.0 67.5 68.0 Freq =
1000 51.5 40.5 43.5 49.5 54.5 58.5 62,0 Freq =
1250 48.1 40.5 43.5 47.0 50.0 56.5 57.5 Freq =
1600 48.2 41.0 43.0 47.0 50.5 57.0 57.5 Freq =
2000 45.8 40.5 40.5 43.5 49.0 53.0 54.0 Freq =
2500 44.3 40.5 40.5 42.5 47.0 51.0 51.5 Freq =
3150 44.9 40.5 40.5 42.0 49.0 52.0 53.5 Freq =
4000 44.1 40.5 40.5 42.0 47.5 50.0 51.0 Freq =
5000 42.3 40.5 40.5 41,0 45.0 47.0 47.0 Freq =
6300 42.9 42.0 42.0 42.5 44.0 46.5 46.5 Freq =
8000 41.7 41.0 41,0 41.5 42.0 44.5 44.5 Freq = 10000 42.2 41.5 41.5 42,0 42.5 43.5 46.0
'A' Weighted 72.3 63.0 67.0 71.5 75.0 76.0 76.5 Linear 77.8 70.0 73.0 76.5 80.5 81.5 82.0 3-5 WYLE LABORATORIES
Table 4(a)
Statistical Characteristics of Ambient Noise Recorded at Location C21 (24 May 1982)
ZONE LOCATION C21 TYPE (S OR A) A Leq L99 L90 L50 L10 Li LO Freq =
100 46.8 36.5 41.0 45.5 49.0 55.0 55.5 Freq =
125 40.9 31.5 33.0 38.5 44.0 48.0 52.5 Freq =
160 44.3 33.0 35.0 43.5 46.0 52.5 54.0 Freq =
200 42.4 29.0 31.5 39.0 46.0 51.0 52.0 Freq =
250 38.3 27.0 29.0 34.5 41.0 48.0 52.5 Freq =
315 39.0 26.0 28.0 34.0 42.5 50.5 51.5 Freq =
400 35.8 23.0 24.5 30.0 39.5 46.0 46.5 Freq =
500 35.4 21.5 24.0 30.5 39.5 46.5 48.0 Freq =
630 34.5 22.5 24.0 30.5 38.0 44.5 48.5 Freq =
800 34.8 22.0 23.5 30.0 38.0 44.0 49.0 Freq =
1000 37.7 21.5 23.5 36.0 41.5 47.0 48.0 Freq =
1250 35.2 23.0 24.5 32.0 38.5 45.0 47.0 Freq =
1600 34.5 20.5 22.0 31.5 38.0 44.5 47.5 Freq =
2000 35.0 20.5 22.0 32.0 37.5 45.5 46.0 Freq =
2500 35.4 20.5 23.0 33.5 37.0 46.0 46.5 Freq =
3150 34.9 20.5 22.0 34.5 37.0 43.5 44.0 Freq =
4000 35.5 20.5 24.0 35.0 37.5 43.0 44.0 Freq =
5000 36.3 20.5 24.5 36.0 38.5 43.0 44.0 Freq =
6300 33.8 21.0 21.5 32.0 36.5 41.0 42.0 Freq =
8000 31.2 20.5 22.0 31.0 33.0 37.0 40.5 Freq = 10000 28.2 20.5 20.5 28.0 30.5 33.0 34.0
'A' Weighted 47.9 35.5 37.0 46.5 50.0 57.5 59.0 Lineer 61.2 51.0 53.0 59.0 63.0 70.0 70,0 3-6 WYLE LABORATORIES
Table 4(b)
Statistical Characteristics of Siren Sound Level Data Recorded at Location C21 During Siren Test (24 May 1982)
ZONE LOCATION C21 TYPE (S OR A) S Leq L99 L90 L50 L10 Li LO Freq =
100 47.6 35.0 38.5 44.0 51.0 55.5 56.0 Freq =
125 50.3 31.0 35.0 42.5 52.0 64.5 65.0 Freq =
160 57.3 31.5 34.0 44.5 52.5 72.0 72.5 Freq =
200 45.9 30.5 33.0 40.5 49.5 55.5 56.0 Freq =
250 45.0 33.0 36.0 42.5 48.5 52.0 53.0 Freq =
315 69.0 56.0 59.5 66.0 72.5 77.5 78.0 Freq =
400 60.4 49.0 52.5 58.0 64.0 68.0 68.5 Freq =
500 42,3 30.5 33.5 41.0 45.5 48.0 48.5 Freq =
630 58.6 44.5 49.0 55.5 62.0 68.0 68.5 Freq =
800 50.1 40.0 43.0 47.5 53.5 58.5 59.0 Freq =
1000 50.4 37.0 40.5 46.0 53.0 60.5 61.0 Freq =
1250 48.1 34.5 38.5 46.0 51.5 56.5 57.0 Freq =
1600 45.5 33.5 37>0 42.5 48.0 55.0 55.5 Freq =
2000 44.7 32.5 36.0 41,5 48.5 53.0 53.5 Freq =
2500 44.1 33.5 37.5 42.0 47.0 53.0 54.0 Freq =
3150 41.2 31.0 34.0 39.0 44.5 48.5 50.5 Freq =
4000 37.1 30.5 31.0 35.5 40.0 42.5 44.0 Freq =
5000 36.0 30.5 31.0 34.5 39.0 40.5 41.0 Freq =
6300 37.4 30.5 31.5 35.5 40.5 45.0 45.0 Freq =
8000 34.4 30.5 30.5 32.5 38.0 39.5 39.5 Freq = 10000 32.6 30.5 30.5 31.5 34.0 34.5 34.5
'A' Weighted 65.4 56.0 58.5 63.0 68.0 73.5 74.0 Linear 71.8 63.5 65.0 70,5 74.5 78.5 79.0 WYLE LABORATORIES
Table 5 Summary of Siren Test Data (24 May 1982)
Siren Ambient Signal-to Site Signal Level, Noise Level, Noise Ratio, Location L10, dB(C)
L90, dB dB A3 75 58 17 A4 78 47 31 A9 78 56 22 A10 82 49 33 A12 77 57 20 B5 61 44 17 B6 75 46 29 B7 75 38 37 B8 80 49 31 BIO 62 56 6
BI I Audible 62 B13 69 45 24 B14 88 68 20 C2 70 44 26 C4 60 56 4
C12 61 38 23 C14 57 39 18 C16 65 39 26 C18 75 57 18 C20 56 51 5
C21 74 34 40 C22 64 53 11 DI 72 57 15 D2 68 56 12 D3 68 56 12 D8 Measurement System Fault D9 67 49 18 DIO 61 46 15 Ell 42 39 3
3-8 WYLE LABORATORIES
3.3 Review of Test Results Of the 29 measurement locations allocated for purposes of the May 24, I 982, test, acoustic data were acquired at all but one of these sites.
The following information relates to these 28 sites:
Total number of measurement locations 28 Locations where signal levels exceeded 60 dB(C) 24 Locations where the signal-to-noise ratio exceeded 10 dB 23 Locations where signal levels exceeded 60 dB(C) and signal-to-noise ratio exceeded 10 dB 22 Combining these test results with those acquired during tests of the siren system during January 25-29, 1982, provides the following overall assessment:
Total number of measurement locations 81 Locations where signal levels exceeded 60 dB(C) and the signal-to-noise ratio exceeded 10 dB 70 This indicates that the currently installed system meets the signal level and signal to-noise criteria at 86 percent of the randomly selected measurement locations.
3-9 WYLE LABORATORIES