Document YGxj1owQK2EbYy7p21rdpeaz8
ETHYL HELLAS CHEMICAL COMPANY S.A.
confidential
To : Mr. J.E. Rogers */ From % B.J. Lentz / S,B. Themolidis Subject: Lead-In--Air Audit
Thessaloniki Thessaloniki Nov. 7 1 196?
The first lead-in-air audit of the Ethyl Hellas Plant was made beginning on October 23 and ending November 3 1967. The audit included:
1. An inspection of the sample stations (condition of equipment and adequacy of location).
2. A check of the lead-in-air meter calibration facilities.
3. A check of the laboratory procedure for handling lead-in-air samples. Analyses to check the scrubbers and separatory funnels for residual lead. Analyses of several known samples by laboratory personnel to check accuracy.
The details of the audit are first discussed followed by recommendations to improve the plant wide lead-in-air sampling and analysis program.
' I , Inspection Tour
All thirteen lead-in-air stations were inspected and the following observations made.
a. Equipment.
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The equipment (rubber tubing, charcoal scrubbers, iodine
scrubbers) were generally in good condition.
However, better maintenance is needed on some of the
stations.
b. TEL vs TML Stations.
Air samplers are of the TEL and TML type. The TEL type
Consists of a single iodine- scrubber. This type of
scrubber collects virtually all of the TEL present in the
air sample. The TML Sampler consists of two iodine scrubbe
operated in series, The double scrubbers are required to
efficiently collect T h L from the air sample since TML is
more difficult to absorb than Is TEL, TML samplers are
installed only in the 1st floor Blonder Area, 2nd floor
B&D Area, and 3rd floor E&D Area. For the supply air only
a TEL type sampler is installed. However, there would
appear to be an equal opportunity for THL to be present in
the supply air.
in certain other areas we are not
sure whether TML is present to a large extent, since in
these areas only TEL samplers are installed.
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c. Air Leakage of Samplers. A leak cheek was performed by capping the air inlet connection of the iodine scrubbersi waiting five minutes for the system to roacn equilibrium, and observing the flow indicator noodle on the face of the dry test meter. a leak was indicated if the flow indicator noodle continued to move. Twelve ol the tnirteen units leaked. It is probable that the leaks are a result of the rubocr tubing connections not being tight.
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d. Height of Station. The height of all but two of the air intakes to the samplers was more than 150 cm above floor level. Some intakes were at a height of 18 0 - 19 0 cm which is above the normal air intake of the human body. Thus, the sampler does not sample the same air an average height person breathes. Also, more TEL and TML contamination would be expected to
be found closer to floor level. It is not known how or why
the original heights were selected.
e. Position. Three samplers (1st floor Blender, 2nd floor E&D, 4th floor E&D) are located near a steady stream of fresh air from the ventilation system. Therefore the samples from
these stations are not believed representative.
f. Inorganic Load Samplers.
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Only one inorganic lend sampler is located, in the Furnace
Area. Samplers of this kind are not located in the Alloy
Hopper and Flaker Areas. Samplers in these areas wore
installed at the beginning of the operation of the plant
but little or no inorganic load was found and they were
eliminated.
I I . Calibration of Meters
The meters are calibrated by using compressed air flowing through a Fisher-Forter rotameter (Model 10A17375). No special procedure|is used during the calibration in order to reproduce conditions similar tc plant conditions.
Also a scheduled calibration of the meters is not set up at the present time.
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III. Laboratory Techniques for Lead-In-Air Samples.
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The procedure used by laboratory personnel to handle the lead-in-air samples was reviewed. The techniques used in removing the samples from the scrubbers, the analyzing of the samples and the cleaning of the scrubbers prior to reuse appeared to be satisfactory. 'Blank solutions of the laboratory reagents and distilled water were being run routinely.
To check the cleanliness of the scrubbers and separatory funnels, two of each were taken at random and analyzed for residual lead. In all cases NIL Pb was found.
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The accuracy of the analyses was checked by having laboratory personnel analyze samples containing quantities of lead known, only to tne person preparing the samples. The results obtained in analyzing these known samples are presented below:
Analysis of Known Samples
Sample
Actual
Hellinge
Mg Pb/ft^air
13 25
3 15 h8 5 10 6 13
0 .0 0 1 0 .0 0 1 0.004
0 .0 0 2 0 .0 0 2 0 .0 0 3
Found
Hellinge
Mg Pb/ft^air
8 0 .0 0 2 *1 0 . 0 0 1 15 0 .00*1 8 0 .0 0 2 8 0 .0 0 2
12 0 .0 0 2
In general, good agreement was reached between the lead found by the technician and the known amount. However, since the scale of the Hellinge numbers is 1,2 ,3 ^ ,6 ,8 ,10,1 5 ,20 nnj some uncertainty exist in the determination of the Hellinge number in the intermediate ranges 10-15 and 15-20, (sample No . 6 ), it is suggested that a great deal of care be taken in interpolating between readings in those reanges. It may even be necessary to split the sample when in the above intermediate ranges.
RECOMMENDATIONS
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According to observations made during the audit the following items are recommended:
1. Install for short periods of time two sampling system (1'TEL and 1 TML) in parallel in all areas where only TEL sample stations are installed, to check whether there are any significant differences in the results of the analyses because of TML being present. In cases where a significant difference is found install the TML type sample station on a permanent basis. It was recommended that the Baton Rouge Plant install all TML type, but this substantially increases
; the laboratory work load.
2. Install a TML type sampler at the main supply air station in place of the TEL type now installed.
3 Install for short p e r i o d s 'cf time inorganic lead type samplers
in t he Hopper Booth and-. Flaker Areas If inorganic lead is
found, to# jbej.prp.s^Jijit ip- substantial nmcuxh;` ip's'tall inorganic
lead simpler Is Ih;. tH'-sev two areas, on d permanent feasi'i..
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Check the sampling rains for leaks periodically by capping
the air inlet connection to the iodine scrubbers, TbJs I**vuld be done about once a wr;t^k.
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5. Reduce the height of all sample intakes to 150 cni. which
would allow samples to be taken that more nearly Represent
the air normally breathed.
6 Relocate the samplers on the 1 st floor of the .Blond*, 2 nd
floor of E&D and 4th floor of E&P to an area out of the
direct path of a frsish. air supply*
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7. Establish a routine schedule for calibrating each mete- on a 90 day interval* In order to reproduce conditions similar to that in the plant, use a vacuum pump at a rate of 4-5 scih. for 1 1/2 hours for TEL samplers and 2,5-3 scfh for TML samplers.
8 . Require the laboratory technicians to analyze a known sample of lead periodically to maintain a check on the accuracy of their analytical techniques.
S i 6b t 1 iU
S.L. Themelidis
cc: Messrs.
A.J, Carville E.F, D'iedrich. *" L. N. Georgiadis M. C. Manolopoulcs J.D, Spearman
SBT/BJL/ek
K E 0019568