TITLE:

ES&H Manual

 

DOCUMENT ID:

3230 Communication of Hazards to Visitors

 

 

1.0            Introduction

 

This chapter highlights the environmental, health, and safety (ES&H) hazards that short term visitors should be aware of at Jefferson Lab.  People who work at the Lab receive a more thorough orientation to potential hazards and receive appropriate job-specific training.  Visitors are not expected to be exposed to significant hazards, so only a brief orientation is necessary.

 

Jefferson Lab is classified as a low-hazard facility.  This means that the hazards encountered here are comparable to those typically found in an industrial setting.  There are a few places on-site where minimal personal protective equipment (PPE) is required: hard hats, safety glasses, solid shoes (no open toes or heels), hearing protection.  All visitors must comply with posted PPE notices and the instructions provided by their escort/tour guide.

 

This chapter discusses:

 

The principal hazards at Jefferson Lab for visitors are:

 

2.0            Hazards at Jefferson Lab

 

2.1              Slips and falls

Though Jefferson Lab has unusual equipment and complex activities, the most significant hazards during your visit at Jefferson Lab are likely to be simple slips, trips, and falls.

 

We try to make access convenient, but please watch your step and use designated walkways and hand railings wherever provided.  High heels and sandals are not recommended footwear anywhere on site, and they are not allowed in some areas.  Smooth or badly worn soles can cause slips on wet surfaces.  Please wear comfortable and safe shoes.

 

If you need assistance maneuvering around obstacles, please do not hesitate to ask your escort for help.

 

2.2              Super-cold liquids (cryogens) and oxygen deficiency

 

 

Super-cold liquids are used to cool some of the equipment at the Lab.  The superconducting accelerator modules and experimental-area magnets do not function unless cooled to cryogenic temperatures by liquid helium.  Liquid nitrogen is also used in large quantities.

 

Oxygen deficiency – not having an adequate amount of oxygen to breathe – could occur when these cold liquids are released and then vaporized into clear, odorless gas.  The large amounts of gas produced, when released in an enclosed space, displace or reduce the percentage of oxygen in the air.

 

 

A high-pressure cryogenic gas release could quickly reduce oxygen levels in an enclosed area like the accelerator tunnel.  Buildings and work areas where cryogenic liquids are used are classified according to the severity of their ODH, and are posted with ODH signs (see the following hazard rating explanations).  Untrained individuals are not allowed to enter ODH classified areas without a trained escort, and only after receiving a short briefing on the hazard and escape procedure.

 

The physical indication of a cryogen spill is a water-vapor cloud, and in the case of high pressure, rushing gas sounds.

 

Leave the area immediately if an oxygen deficiency warning blue light flashes or an oxygen deficiency alarm sounds - this alarm is a loud stationary horn from a fixed sensor, or a shrill whistle from a personal monitoring device.

 

In case of an uncontrolled release of cryogens:

·         Warn others and immediately leave the area

·         Never enter a vapor cloud

·         Follow the instructions given by your escort (He or she may ask you to hold your breath until you are out of a vapor cloud, or to use an alternate stairwell or exit to avoid contact with a vapor cloud.).

·         Follow your escort to the nearest, safe exit.

·         Stay calm.

 

You can avoid cryogenic and oxygen deficiency hazards at the Lab by observing and following instructions on posted ODH signs.

 

2.2.1        ODH 0 and ODH 1

Only personnel who have received the Jefferson Lab ODH training or escorted, briefed visitors may enter.  ODH 1 areas also require a second trained person.

 

2.2.2        ODH 2 and ODH 3

Jefferson Lab ODH training, additional specialized training, medical approval, monitoring, multiple personnel, and escape packs are required for entry.  No visitors are allowed.

 

2.2.3        ODH 4

Keep Out.  No areas on site are permanently classified ODH 3 or 4.

 

Text Box: NOTE: If you feel dizzy, have an unexplained loss of coordination, or if your heart rate becomes unusually high, tell your escort and those around you and seek fresh air immediately.

 

2.3              Cranes and hoists (motorized material handling equipment)

Avoid the hazards of cranes and hoists.

·         Stay clear of crane/hoist operations.

·         Observe posted warnings.

·         Follow the directions of those conducting the work.

·         Stay on marked paths.

·         Don’t walk under lift equipment while it is in operation.

 

2.4              Electricity

Essentially all equipment at the Lab is dependent on electrical energy.  Obey posted signs and your escort’s warnings.  Do not handle apparatus or equipment unless you have specific permission to do so from your escort.

 

2.5              Chemicals

Visitors are not authorized to handle or use hazardous chemicals at the Lab.  If you detect a strange odor or see what seems to be a spill, bring it to the attention of your escort, and leave the area with your escort.

 

2.6              Fire

If a fire alarm sounds, leave the building, following your escort’s directions.  If you lose sight of your escort, follow evacuation plans posted on walls throughout Lab work areas.  Exits and exit paths are clearly marked.  Gather at the designated muster points (assembly locations), and await instructions from your escort.

 

2.7              Lasers

 

There are a few high-power lasers in use at Jefferson Lab.  The greatest concern related to lasers is eye safety.  (Exposure to laser light can cause eye injury.)

 

High-power laser systems may also present significant electrical hazards.

 

Avoid exposure to laser hazards by:

·         Never looking directly at or into a laser beam - no matter what the power level.

·         Wear special laser safety glasses, if required.

·         •Following the directions on posted warning signs.

 

2.8              Microwave and radio frequency (RF) radiation

Microwave or RF radiation is usually well contained at Jefferson Lab.  Slight leakage, however, could interfere with instruments and electrical apparatus, including medical devices such as heart pacemakers.  If you wear a pacemaker or other sensitive electronic biomedical equipment, please consult your personal physician prior to entering microwave or RF areas.

 

2.9              Strong Magnetic Fields

 

Jefferson Lab has a few areas (predominantly in the accelerator tunnel and the experimental halls) that contain strong magnetic fields.  Venturing into these magnetic fields could pose safety hazards to individuals with implanted surgical and/or bioelectronic devices (e.g. cardiac pacemaker, heart valve implant, ear implant, aneurysm clip, joint replacement, etc.).  If you might have metal in your body, you should consult your personal physician prior to entering areas that contain strong magnetic fields.  Sources of metal include, but are not limited to residual metal flecks in the eye from past accidents, shrapnel, surgical clips, pins, or other objects or devices that are implanted surgically.

 

Access to these areas is controlled, visitors are escorted, and they receive a magnetic field safety awareness briefing (when they receive the Oxygen Deficiency Hazard [ODH] briefing), before entering areas posted for strong magnetic fields.

 

Posted signs and flashing, red warning lights indicate the presence of potentially high magnetic fields in specific areas.  In most cases, taped/roped-off or blockaded areas indicate the areas of potential reach of these magnetic fields.  Follow your escort’s lead and stay out of and away from these marked areas.

 

2.10          Ionizing radiation

The Lab’s accelerators and some accelerator components produce ionizing radiation, mostly x-rays, during operation.  Component test areas may also generate radiation.  All potential radiation areas are posted with signs and, in some cases, warning lights.  People under age 18 are not allowed to enter radiation areas.  If you are pregnant, it is recommended that you avoid the radiation areas altogether.

 

Please heed the signs and instructions from your escort.  If you are visiting a radiologically controlled area, you will be asked to sign in, and you or a member of your group will be asked to wear an exposure dosimeter (a device which records any radiation exposures.)  Jefferson Lab will notify you in writing if your group receives any measurable exposure.

 

 

3.0            Participation in Tours - Escorts/Visitors

 

Escort Ratios:

 

You may be required to wear a radiation dosimeter.  Your escort will make this arrangement.

 

4.0            Tours of Controlled Areas During Special Events

 

Jefferson Lab periodically hosts special events for visitors numbering from several hundred to several thousand people (e.g. American Physical Society or Division of Nuclear Physics tours, Jefferson Lab open houses, etc.).  For events where large numbers of people will be in Jefferson Lab’s controlled areas, Lab employees must follow Standard Operating Procedures (SOP) DIR-2003-01 titled Tours of Controlled Areas During Special Events.  This SOP sets forth procedures to ensure the safety of visitors during special events.  The SOP is available electronically at https://jlabdoc.jlab.org/docushare/dsweb/Get/Document-11643/DIR-03-001.pdf.

 

5.0            What To Do In An Emergency

 

5.1              Medical Emergencies

·         Dial 9-911 or 911

Give the dispatcher:

o   Your location

o   Type of problem

o   Your name

o   Name and location of injured

·         Then dial ext. 4444 for on-site emergency response and to explain the nature of the emergency

 

5.2              All Jefferson Lab telephones are labeled with:

·         Emergency 911

·         Your Telephone Location

 

5.3              Basic First Aid

·         Dial 7539 (Jefferson Lab Occupational Medicine)

·         Pager # 584-7539 (for the nurse:  Enter your extension, press #, and hang up)

Hours: Monday-Friday, 8am - 5pm

 

Text Box: For all other emergencies follow your escort’s directions.

 

 

 

ISSUING AUTHORITY

CHAPTER AUTHOR

APPROVAL DATE

EFFECTIVE DATE

EXPIRATION DATE

REV.

 

 

 

ESH&Q Division

Debbie Magaldi

06/21/05

06/21/05

06/21/08

0

 

This document is controlled as an on line file.  It may be printed but the print copy is not a controlled document.  It is the user’s responsibility to ensure that the document is the same revision as the current on line file.  This copy was printed on 8/24/2009.