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IODINE†
| CAS # | 7553-56-2 |
|---|---|
| Formula |
I₂ |
| Synonyms |
iodine crystals; molecular iodine |
| Physical description | Violet-black crystals with metallic luster and a sharp, characteristic odor. | ||
|---|---|---|---|
| Boiling point | 365°F | Molecular weight | 253.8 |
| Freezing point/melting point | 236°F | Vapor pressure | 0.3 mmHg at 77°F |
| Flash point | Vapor density | ||
| Specific gravity | 4.93 | Ionization potential | 9.31 eV |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1515 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | sampling glass tubes packed with 100 mg IABC front and 50 mg backup sections [SKC 226-80 or equivalent] |
| Sampling time* | 5 min |
| Sampling volume (TWA)* | 2-5 L |
| Sampling flow rate (TWA)* | 0.5 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | ISE |
| Method reference | OSHA ID-212 (fully validated) |
| Notes | Humidity at the sampling site needs to be assessed prior to the actual sampling. FOR OSHA CSHOs ONLY: If it is anticipated to be greater then 50%, please contact the SLTC for further instructions. Submit as separate sample. When the analysis of this compound is requested, analysis for Iodide is performed and reported as Iodine. |
| Special requirements |
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media | OSHA STAFF CONTACT SLTC FOR MEDIA |
|---|---|
| Bulk Method |
| Device | Detector tube | Detector tube |
|---|---|---|
| Model/Type | Gastec 9L | Gastec 80 |
|
Sampling information (see manufacturer instructions) |
1-2 strokes, 0.04-12 ppm range, uncertainty 16% for 0.2-1.2 ppm, 8% for 1.2-12 ppm | 1-4 strokes, approx 0.3-48 ppm range, uncertainty 16% |
|
OSHA PEL
8-hour TWA (ST) STEL (C) Ceiling Peak |
NIOSH REL
Up to 10-hour TWA (ST) STEL (C) Ceiling |
ACGIH TLV©
8-hour TWA (ST) STEL (C) Ceiling |
|||||
|---|---|---|---|---|---|---|---|
| PEL-TWA | REL-TWA | TLV-TWA |
0.01 ppm (inhalable fraction and vapor) [2007] |
PEL-TWA | |||
| PEL-STEL | REL-STEL | TLV-STEL |
0.1 ppm (vapor fraction) [2007] |
PEL-STEL | |||
| PEL-C |
0.1 ppm (1 mg/m³) |
REL-C |
0.1 ppm (1 mg/m³) |
TLV-C | PEL-C |
0.1 ppm (1 mg/m³) |
|
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: | Notes: | Notes: | Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH |
2 ppm |
|||||
| Carcinogenic classifications: TLV-A4 | Notes: | ||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
0.1 ppm/0.5 ppm/5 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Iodine NIOSH: Pocket Guide to Chemical Hazards - Iodine Literature References
|
Last Updated Date : 01/29/2021