# Presentation: 792450

## Issues Dealing With Safe Handling of Mercury

**Philip T. Spampinato**
**(spampinatop@ornl.gov, 865-576-5267)**
**Van B. Graves**
**Tony A. Gabriel**

**MERIT Review Meeting**
**December 12, 2005**
**Brookhaven National Laboratory**
**Upton, NY**

## Outline

**Properties, Safety Limits**
**Background - SNS Target Test Facility**
**Installing Hg & New Equipment into TTF**
**Hg Vapors & Air Filtration**
**Filling the Target Loop**
**What if ...?**
**Conclusions**

## Properties and Safety Limits

**Atomic Weight: 200.59**
**Boiling Point: 357****°**** C**
**Specific Gravity: 13.6**
**Vapor Pressure: 0.0012 mm Hg**
**Vapor Density: 7.0 (air = 1.0 @ 20****° C)**
**Vapor: colorless, odorless**
**Solubility: insoluble in water**
**NIOSH/OSHA: 0.05 mg/m****3****, 10 h/day; 40 h/wk**
**TTF: action level is set to 0.0125 mg/m****3**
**Use respirator with Hg cartridge**

## Mercury Health Effects

## Mercury First Aid Instruction

## Mercury Vapors

***Video clip of Hg vapors at RT***
_**[http://www.](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[deq](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[.state.mi.us/documents/](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[deq](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[-](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[ead](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[-p2-mercury-bb-Vapors.](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**__**[wmv](http://www.deq.state.mi.us/documents/deq-ead-p2-mercury-bb-Vapors.wmv)**_

**Vapors can only be “seen” with a vapor monitor!**

## The Target Test Facility (TTF) - Background Information

**Full scale, prototype of the SNS Hg flow loop**
**1400 liters of Hg**
**Used to determine flow characteristics**
**Develop hands on operating experience**
**Assess key remote handling design issues**
**MERIT assy & testing May-Aug ‘06**

**MERIT**

## TTF Pump Room and Target Room

**75-hp centrifugal pump**
**Nominal flow at 1450 liters/min (380 gpm)**
**Several equipment upgrades to the piping and target module were successfully completed**

## Mercury Containers/Shipping

**Standard flask is 2 liters**
**Flask + Hg weighs ~35 kg**

## TTF Operations – Hg Filling

**A peristaltic pump for transferring Hg was successfully tested**
**This is the preferred approach for filling the MERIT**

## Filling (cont.)

**TTF vacuum pump was used to transfer Hg directly into the storage tank**
**Lower risk than using the peristaltic pump for 700 flasks**
**Faster operation, ~ 1-1/2 minutes per flask**

**Snorkel**

## Filling MERIT

**Secondary containment cover remains installed**
**Pump directly into the sump tank**
**Air displaced from the sump tank is vented through the primary passive filter**
**The portable snorkel is placed near the passive filter**
**Glovebox could used if required**
**Not considered to be necessary for MERIT**

**Snorkel**

## Mercury Monitoring

**TTF Uses Jerome 431-X Vapor Analyzers**
**One monitor dedicated to each room and connected to the Target Test Facility PLC**
**sample every 5 minutes**
**battery recharge every 24 hours**
**Portable monitor used during interventions **
**The Jerome analyzer has a range of 0.000 – 0.999 mg/m****3**
**Sensitivity is 0.003 mg/m****3**
**Measures the change in resistance across a gold film as a function of adsorbed Hg vapor**
**Other monitors are available, including those that use UV absorption**

## MERIT at MIT and CERN

**Dialogue with the MIT Safety Engineering Group has begun**
**Presentation/discussion with CERN in August ’05**
**Visual confirmation of off-normal events**
**Presentation/discussion with MIT at the October Collaboration Meeting**
**Safety review and target test plan to be presented to MIT in March ‘06**
**In additon:**
**CERN will provide a second (portable) vapor monitor for sampling the tunnel environment**
**MIT and CERN will provide support for repackaging the target equipment and Hg for delivery back to ORNL**

## Scavenger – A Portable Snorkel

**Use snorkel near open flasks in lieu of glove box**
**Connect snorkel to passive filter port during filter cartridge replacement**

**HEPA**
**Filter**

**Sulfide-**
**Charcoal**
**Filter**
**(6 lbs)**

## Filter Replacement

**Filter replacement requires opening the secondary containment**
**To replace primary passive filter attach snorkel to the secondary filter port**
**Tunnel air is drawn into the secondary containment during filter replacement**
**Monitor the area adjacent to the filter**

## TTF Ventilation System

**5 air changes/h**
**Flow velocity at 25-32 ft/s (~9 m/s)**
**Sulfide-impregnated charcoal filter (400 lbs) in-line with the building ventilation**

## Filter Replac. (cont.)

**Secondary Filter**

**Primary Filter**

## Filter Lifetime - Prelim. Calculation

***Ref. Quechsilber und seine Gefahren, Swiss government worker safety report, SBA No. 145, Luzern***

**Saturation Concentration**

**Saturation Pressure**

** ****Flow Rate  110 cfm**
** ****Temp.  25 ****0****C**
** ****Filter Effic.  99.0%**

** ****Filter Weight  6 lbs**
** ****Sulfide Material  12% by weight**
** ****Filter Life  185 hrs**
***Does not incl. reduction for humidity***

## Action Scenarios (Prelim.)

**Vapors detected outside of secondary containment by monitor # 2 - assume the secondary containment is breached or that the filter is saturated**
**Confirm with readings from #1 vapor monitor**
**If confirmed ... cease operations**
**Monitor target instruments for clues to the source of leakage**
**verify by checking sump tank level sensor, conductivity sensor, and nozzle pressure sensor**
**Wait for cool down, visually inspect and sample local air**
**If levels are above action limit (0.0125 ****mg/m****3****), inspect with full face mask-Hg respirator cartridges**
**Repair breach in enclosure if possible, pressure check, continue test operations**

## Miscellaneous Safety-Related Items

## Operations Experience: Installation of He Bubbler

**Bubbler test equipment was recently added to TTF**
**He leak tested all joints at 25 psig before filling with Hg**

## Proper Attire Is Required 

**Overalls, gloves, and overshoes are the minimum requirement**

## Mercury Puddling

**Mercury will collect into small droplets and large puddles even in pipes sloped at 1 degree**

## Mercury Decontamination and Cleanup – Routine Decon

**Hg-X is a water soluble, metallic-mercury/sulfide converting powder with a chelating compound and dispersing agent**
**Forms a film over finely divided Hg beads, producing a non-vaporizing sulfide**
**Mix with water as needed**
**Apply with sponge**
**Low cost**

## Mercury Decon/Cleanup (cont.)

**HEPA Vacuum**
**RCRA and non-RCRA waste collection**

## Conclusions

**Reviewed Hg properties and safety limits**
**Nothing unmanageable**
**Short of an uncontained spill vapors, are the main concern**
**Use of vapor monitors, air filters, snorkel**
**Experience from operating SNS/TTF valuable for MERIT**
**Fill MERIT with a peristaltic pump; make extensive use of spill containment; He leak check before operating**
**Vapor monitors always in use; decontamination using Hg-X and HEPA vacuum**
**Starting to develop list of off-normal events and actions**
**Handling activated mercury requires these same precautions and procedures, but at an even higher level of alertness**