Radionuclide Safety Sheets

  • Symbol: 14C
  • States/Forms: Soluble, except gaseous

Physical Characteristics

  • Radioactive Half Life (T½): 5730 years
  • Decay Type: Beta- (ß-)
  • Maximum Energy Emission: 0.156 MeV
  • Maximum Range in Air: 21-25 cm
  • Maximum Range in Water/Tissue: 0.028 cm
  • Maximum Range in Plexiglas or Lucite: 0.025 cm

Hazard Category

  • A Level (High Hazard): >1.0 Ci
  • B Level (Moderate Hazard): >10 mCi to 1.0 Ci
  • C Level (Low Hazard): 0.1 mCi to 10 mCi

Radiological Characteristics

  • 17% of beta particle energy transmitted through dead layer of skin.
  • Critical organ: Fat tissue.
  • Routes of intake: Ingestion, inhalation, puncture, wound, skin contamination (absorption).
  • Internal exposure and contamination: Primary radiological concerns with 14C.
  • External exposure: External exposure from weak 14C beta particles is not a major radiological concern.

Dosimetry

Film badges and dosimeter rings are not appropriate for monitoring 14C exposure.

Bioassay Requirements

Urinalysis and breath measurements of CO2 may be required after spills or incidents of contamination.

External Radiation Hazards and Shielding

There is minimal external hazard with 14C, i.e. the glass vial containing the 14C provides sufficient shielding from the beta particles. If the skin is uniformly contaminated with 14C, 1 microcurie/cm2 (µCi/cm2) will deliver a dose of 1100 miilirems per hour (mrems/hr) to the basal skin cells.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake)
  • 2400 µCi - by ingestion
  • 2000 µCi - by inhalation
  • DAC (Derived Air Concentration)
  • 1 x 10-6 µCi/mL

Survey Instrumentation

  • A Geiger-Muller pancake/frisker can be used to detect 14C, however the survey meter probe must be within a very close range (< 1 inch).
  • Geiger-Muller detectors have a very low efficiency (~3%) for counting low energy 14C beta particles.
  • Smear surveys, using liquid scintillation counters, are required to detect removable 14C contamination.

Problems and Precautions

  • Lab coats and protective gloves should always be worn when working with 14C to keep skin free from contamination, and gloves should be changed often.
  • All waste in a 14C work area is considered to be contaminated. Work areas should be kept free of unnecessary items.
  • Wastes should be segregated to those with 3H and 14C only.
  • It is assumed that ingested or inhaled 14C labeled compounds are instantaneously distributed uniformly throughout the organs and tissues of the body, where they are retained with a biological half-life of 40 days.
  • Symbol: 51Cr
  • States/Forms: Soluble

Physical Characteristics

  • Radioactive Half Life (T½): 27.7 days
  • Decay Type: Electron (e-) capture, Gamma, X-ray
  • Maximum Energy Emissions:
  • 0.752 MeV (e- capture)
  • 0.320 MeV (Gamma)
  • 0.005 MeV (X-ray)

Hazard Category

  • A Level (High Hazard): >1.0 Ci
  • B Level (Moderate Hazard): >200 mCi to 1.0 Ci
  • C Level (Low Hazard): 0.1 mCi to 200 mCi

Radiological Characteristics

  • Critical organs: Liver (25%), bone (5%), lower large intestine, and kidneys
  • Routes of intake: Ingestion, inhalation, skin contamination (absorption).
  • Internal exposure and contamination: Primary radiological concerns with 51Cr.
  • External exposure: Primary radiological concern with 51Cr.

Dosimetry

Film badges and dosimeter rings are required if 10 millicuries (mCi) or more is to be handled at a given time, or if 5 mCi levels are handled frequently.

Bioassay Requirements

Whole body monitoring. Urinalysis may be done.

External Radiation Hazards and Shielding

The exposure rate at 1 cm from 1 mCi is 180 millirads per hour (mR/hr).  The exposure rate varies directly with activity and inversely with the square of the distance.  ¼ inch of lead shielding should be used when working with concentrations > 1 microcurie (μCi).  ½ inch of lead shielding should be used when working with concentrations > 10 μCi.   

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake):
  • 4 x 104μCi – by ingestion
  • 5 x 104μCi – by inhalation   
  • DAC (Derived Air Concentration):
  • 2 x 10-5 µCi/mL

Survey Instrumentation

  • Liquid scintillation counter (efficiency 37%)
  • NaI scintillation counter (efficiency 1-2%)

Problems and Precautions

  • Lead shielding should be used when working with or storing 10 mCi of 51Cr or greater.  Stock solution vials should be handled in shields or with tongs or forceps.
  • Lab coats and protective gloves should always be worn when working with 51Cr to keep skin free from contamination, and gloves should be changed often.
  • Survey frequently.
  • Waste should be segregated to those with half-lives from 15 days to less than 60 days.
  • Symbol: 125I
  • States/Forms: Inorganic, Free Iodine

Physical Characteristics           

  • Radioactive Half Life (T½): 60 days
  • Decay Type: Electron (e-) capture, Gamma
  • Maximum Energy Emission: 0.035 MeV (Gamma)

Hazard Category

  • A Level (High Hazard): >10 mCi
  • B Level (Moderate Hazard): >200 μCi  to 10 mCi
  • C Level (Low Hazard): 0.1 μCi to 200 μCi

Radiological Characteristics

  • Critical organ: Thyroid
  • Routes of intake: Ingestion, inhalation, skin contamination (absorption).
  • Internal exposure and contamination: Primary radiological concerns with 125I
  • External exposure: Concern for 125I.                                                        

Dosimetry

Film badges and dosimeter rings are required if 5 millicuries (mCi) or more is to be handled at a given time, or if mCi levels are handled frequently.

Bioassay Requirements

Thyroid scans.

External Radiation Hazards and Shielding

The exposure rate at 1 cm from 1 mCi is 1.5 rads per hour (R/hr).  The exposure rate varies directly with activity and inversely with the square of the distance.  1/32 of an inch of lead shielding should be used when working with concentrations > 1 microcurie (μCi).  ½ inch of lead shielding should be used when working with concentrations > 1 mCi.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake):
  • 400 μCi – by ingestion
  • 600 μCi – by inhalation
  • DAC (Derived Air Concentration):
  • 3 x 10-8 µCi/mL

Survey Instrumentation

  • GM survey meters have a poor efficiency of detection for 125I. 

  • Survey by smear test or use NaI (TI) Scintillation probes.



Problems and Precautions

  • Store NaI-125 solutions at room temperature because freezing results in subsequent volatilization of radioiodine. 

  • Avoid acidic solutions to minimize volatilization. 

  • Wear two pair of gloves when handling radioiodine compounds.
  • Symbol: 32P
  • States/Forms: Soluble

Physical Characteristics

  • Radioactive Half Life (T½): 14.3 days
  • Decay Type: Beta-)
  • Maximum Energy Emission: 1.71 MeV
  • Maximum Range in Air: 611 cm
  • Maximum Range in Water/Tissue: 0.76 cm
  • Maximum Range in Plexiglas or Lucite: 0.61 cm

Hazard Category

  • A Level (High Hazard): >100 mCi
  • B Level (Moderate Hazard): >2 mCi to 100 mCi
  • C Level (Low Hazard): 0.01 mCi to 2 mCi

Radiological Characteristics

  • 95% of beta particle energy transmitted through dead layer of skin.
  • Critical organs: Body tissues – 70%; Bone – 30%
  • Routes of intake: Ingestion, inhalation, puncture, wound, skin contamination (absorption).
  • Internal exposure and contamination: Primary radiological concerns with 32P
  • External exposure: Primary radiological concern with 32P. 

Dosimetry

Film badges and dosimeter rings are required if 1 millicurie (mCi) or more is to be handled at a given time, or if millicurie levels are handled frequently.

Bioassay Requirements

Urinalysis may be required after spills or incidents of contamination.

External Radiation Hazards and Shielding

Assuming there is no backscatter or self-absorption, the dose rate at 10 cm is 2.7 rads/hour from an unshielded 1 mCi dried sample of 32P.  If the skin is contaminated with 32P, 1 microcurie/cm2 (μCi/cm2) will deliver a dose of 9200 miilirads per hour (mrad/hr) to the basal cells of the epidermis.  Lead foil or sheets, or other high density materials should NEVER be used to shield 32P directly due to the production of penetrating Bremsstrahlung x-rays.  Lead materials can be used as shielding from Bremsstrahlung x-rays ONLY if behind low-density plexiglass, acrylic, lucite, or wood shielding.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake):
  • 600 μCi – by ingestion (all compounds)
  • 900 μCi – by inhalation (except phosphates)
  • 400 μCi – by inhalation (phosphates)
  • DAC (Derived Air Concentration):
  • 2 x 10-5 μCi/mL

Survey Instrumentation

  • A Geiger-Muller survey detector with a pancake/frisker probe can be used to detect 32P.  The counting efficiency for 32P is approximately 25%.
  • A low-energy NaI probe can only be used to detect Bremsstrahlung x-rays.
  • Liquid scintillation counters should be used to detect removable surface 32P contamination using smears or swabs.

Problems and Precautions

  • Phosphorus-32 is commonly the highest energy radionuclide encountered in a research setting, and thus requires special caution.  Exposure should be avoided and handling should be limited as much as possible.
  • Always wear a lab coat, disposable gloves, and safety goggles when working with 32P.
  • Bremsstrahlung x-ray production must be avoided by working behind low Z shielding, preferably transparent materials.
  • Surveys should be conducted frequently and gloves should be changed often.
  • Waste should be segregated to those with half-lives of less than 19 days.
  • Symbol: 33P
  • States/Forms: Soluble

Physical Characteristics

  • Radioactive Half Life (T½): 25 days
  • Decay Type: Beta-)
  • Maximum Energy Emission: 0.249 MeV
  • Maximum Range in Air: 49 cm
  • Maximum Range in Water/Tissue: 0.06 cm
  • Maximum Range in Plexiglas or Lucite: 0.05 cm

Hazard Category

  • A Level (High Hazard): >1 Ci
  • B Level (Moderate Hazard): >20 mCi to 1 Ci
  • C Level (Low Hazard): 0.1 mCi to 20 mCi

Radiological Characteristics

  • 40% of beta particle energy transmitted through dead layer of skin.
  • Critical organs: Bone marrow – 30%; Body tissues – 70%
  • Routes of intake: Ingestion, inhalation, puncture, wound, skin contamination (absorption).
  • Internal exposure and contamination: Primary radiological concerns with 33P.
  • External exposure: Minimal concern for 33P.

Dosimetry

Film badges and dosimeter rings are not appropriate for monitoring 33P exposure.

Bioassay Requirements

Urinalysis may be required after spills or incidents of contamination.

External Radiation Hazards and Shielding

There is minimal external hazard with 33P, i.e. the glass vial containing the 33P provides sufficient shielding from the beta particles, however lucite or plexiglas may be used as shielding.  If the skin is uniformly contaminated with 33P, 1 microcurie/cm2 (Ci/cm2) will deliver a dose of 3200 miilirems per hour (mrems/hr) to the basal skin cells.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake):
  • 4000 μCi – by ingestion
  • 6000 μCi – by inhalation
  • DAC (Derived Air Concentration):
  • 3 x 10-6 μCi/mL

Survey Instrumentation

  • A Geiger-Muller survey detector with a pancake/frisker probe can be used to detect 33P.  The counting efficiency for 33P is approximately 6%.
  • Liquid scintillation counters should be used to detect removable surface 33P contamination using smears or swabs.

Problems and Precautions

  • Lab coats and protective gloves should always be worn when working with 33P to keep skin free from contamination, and gloves should be changed often.

  • All waste in a 33P work area is considered to be contaminated.  Work areas should be kept free of unnecessary items.

  • Drying can form airborne 33P contamination.

  • Waste should be segregated to those with half-lives from 19 days to less than 65 days.
  • Symbol: 35S
  • States/Forms: Soluble, except gaseous

Physical Characteristics

  • Radioactive Half Life (T½): 87 days
  • Decay Type: Beta-)
  • Maximum Energy Emission: 0.167 MeV
  • Maximum Range in Air: 26 cm
  • Maximum Range in Water/Tissue: 0.04 cm
  • Maximum Range in Plexiglas or Lucite: 0.025 cm

Hazard Category

  • A Level (High Hazard): >1 Ci
  • B Level (Moderate Hazard): >20 mCi to 1 Ci
  • C Level (Low Hazard): 0.1 mCi to 20 mCi

Radiological Characteristics

  • ~15% of beta particle energy transmitted through dead layer of skin.

  • Critical organs: Testes

  • Routes of intake: Ingestion, inhalation, puncture, wound, skin contamination (absorption).

  • Internal exposure and contamination: Primary radiological concerns with 35S.

  • External exposure: Minimal concern for 35S. 


Dosimetry

Film badges and dosimeter rings are not appropriate for monitoring 35S exposure.

Bioassay Requirements

Urinalysis may be required after spills or incidents of contamination.

External Radiation Hazards and Shielding

There is minimal external hazard with 35S, i.e. the glass vial containing the 35S provides sufficient shielding from the beta particles, however lucite or plexiglas may be used as shielding.  If the skin is uniformly contaminated with 35S, 1 microcurie/cm2 (μCi/cm2) will deliver a dose of 1200 miilirads per hour (mrad/hr) to the basal skin cells.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake):
  • 1 x 104μCi – by ingestion
  • 6 x 10-6μCi – by inhalation
  • DAC (Derived Air Concentration):
  • 2 x 10 -8 µCi/mL

Survey Instrumentation

  • A thin window Geiger-Muller detector can be used to detect 35S, however the survey meter probe must be within a very close range (< 1 inch).
  • A Geiger-Muller survey detector with a pancake/frisker probe has a very low counting efficiency for 35S (~4%).
  • Liquid scintillation counters should be used to detect removable surface 35S contamination using smears or swabs.

Problems and Precautions

  • Lab coats and protective gloves should always be worn when working with 35S to keep skin free from contamination, and gloves should be changed often.

  • All waste in a 35S work area is considered to be contaminated.  Work areas should be kept free of unnecessary items. 

  • 35S compounds are often volatile or produce volatile products.  35S should be opened and handled in a fume hood. 

  • Activated charcoal should be used when incubating samples. 

  • Waste should be segregated to those with half-lives from 65 days to less than 90 days.
  • Symbol: 3H
  • States/Forms: Soluble, except gaseous

Physical Characteristics

  • Radioactive Half Life (T½): 12.3 years
  • Decay Type: Beta-  -)
  • Maximum Energy Emission: 0.0186 MeV
  • Maximum Range in Air: 0.6 cm
  • Maximum Range in Water/Tissue: 0.0006 cm

Hazard Category

  • A Level (High Hazard): >10.0 Ci
  • B Level (Moderate Hazard): >25 mCi per item to 10.0 Ci possession
  • C Level (Low Hazard): 1-25 mCi per item to 100mCi possession

Radiological Characteristics

  • 0% of beta particle energy transmitted through dead layer of skin.

  • Critical organ: Body water or tissue.

  • Routes of intake: Ingestion, inhalation, puncture, wound, skin contamination (absorption).

  • Internal exposure and contamination: Primary radiological concerns with 3H.

  • External exposure: External exposure from weak 3H beta particles is not a major radiological concern


Dosimetry

Film badges and dosimeter rings are not appropriate for monitoring 3H exposure.

Bioassay Requirements

Routine urinalysis is required after handling 100 microcuries (μCi) or greater of 3H.  Spot checks may be necessary following spills or incidents of contamination.

External Radiation Hazards and Shielding

There is minimal external hazard with 3H, i.e. the vial containing the 3H provides sufficient shielding from the beta particles.  If the skin is contaminated with 3H, the betas will not be able to penetrate through the dead layer of skin.  However, if 3H is absorbed into the body via ingestion or cuts in the skin, it will cause a radiation dose.

Hazards if Internally Deposited

  • ALI (Annual Limit of Intake)
  • 80 mCi – by ingestion or inhalation
  • DAC (Derived Air Concentration)
  • 2.0 x 10-5 μCi/mL

Survey Instrumentation

  • Tritium cannot be detected using a Geiger-Muller or NaI survey meter.

  • Smear surveys, using liquid scintillation counters, are required to detect 3H contamination.



Problems and Precautions

  • Lab coats and protective gloves should always be worn when working with 3H to keep skin free from contamination, and gloves should be changed often.

  • All waste in a 3H work area is considered to be contaminated.  Work areas should be kept free of unnecessary items.

  • Wastes should be segregated to those with 3H and 14C only.

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