CHLORINE†
| CAS # | 7782-50-5 |
|---|---|
| Formula |
Cl₂ |
| Synonyms |
molecular chlorine; bleach |
| Physical description | Greenish-yellow gas with a pungent, irritating odor. | ||
|---|---|---|---|
| Boiling point | -29°F | Molecular weight | 70.9 |
| Freezing point/melting point | -150°F | Vapor pressure | 6.8 atm |
| Flash point | Vapor density | 2.47 | |
| Specific gravity | 1.424 at 59°F | Ionization potential | 11.48 eV |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 4 | NFPA fire rating | 0 |
| NFPA reactivity rating | 0 | NFPA special instruction | OX: Possesses oxidizing properties |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 0640 | 0640 |
|---|---|---|
| Sampling group | ||
| Sampler/Sampling media | Dräger X-am 5600 Multi-Gas Detector with a Dräger XXS NO electrochemical sensor | Midget fritted glass bubbler (MFGB) containing sulfamic acid solution (0.1%) - Chlorine Sampling Solution [SLTC112SOL]; PTFE, 25 mm, 0.45 µm pore [SKC 225-17-04]; Polypropylene Support Pad, 25 mm, [SKC 225-2901], Conductive Polypropylene Cassette Blank, goblet style, black, 25 mm, [SKC 225-2257] |
| Sampling time* | Up to 16 hours due to monitor datalogger capacity |
240 min |
| Sampling volume (TWA)* | 240 L |
|
| Sampling flow rate (TWA)* | 1 L/min |
|
| Sampling volume (STEL/Peak/C)* | 15 L |
|
| Sampling flow rate (STEL/Peak/C)* | 1 L/min |
|
| Analytical method instruments | ISE | |
| Method reference | OSHA 1030 (fully validated) | OSHA ID-101 (fully validated) |
| Notes | Chlorine containing compounds, such as hypochlorites and trichloroisocyanuric acid, can act as positive interferences. If they are expected in the workplace, use a PTFE membrane/polypropylene cassette as a prefilter, followed by the midget fritted glass bubbler (MFGB) containing 15 mL 0.1% Sulfamic Acid for Chlorine Collection. PTFE prefilter does NOT need to be sent in to SLTC for Chlorine analysis. Note: Do not use this method when bromine, fluorine, chlorine dioxide or hydrogen sulfide are present. |
|
| Special requirements | These media are prepared by SLTC as needed and are not available for immediate shipment. Please allow time for SLTC to prepare these media prior to sampling. |
* 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 | |
|---|---|
| Bulk Method | Available |
| Device | Detector tube | Detector tube | CMS Chip |
|---|---|---|---|
| Model/Type | Matheson-Kitagawa 8014-109SB | Gastec 8LA | Chlorine, 0.2-10 ppm range |
|
Sampling information (see manufacturer instructions) |
follow mfr instructions, approx 0.1-10 ppm range | 0.5-5 strokes, 0.05-16 ppm range, uncertainty 16.4% for 0.5-2 ppm, 8.2% for 2-8 ppm |
|
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 |
1 ppm (3 mg/m³) [Construction and Maritime Industries only] |
REL-TWA | TLV-TWA | PEL-TWA |
0.5 ppm (1.5 mg/m³) |
||
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL |
1 ppm (3 mg/m³) |
|||
| PEL-C |
1 ppm (3 mg/m³) [General Industry only] |
REL-C |
0.5 ppm (1.45 mg/m³) [15 minutes] |
TLV-C | PEL-C | ||
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
|
Notes:
See 29 CFR 1910.1000 Table Z-1 The OSHA PEL for an 8 hr time-weighted average applies to Construction and Maritime Industries only. See 29 CFR 1926.55 Table 1 and 29 CFR 1915.1000 Table Z-Shipyards |
Notes: |
Notes:
Visit the ACGIH TLV site for specific data |
Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH |
10 ppm |
|||||
| Carcinogenic classifications: TLV-A4 | Notes: | ||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
1 ppm/3 ppm/20 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Chlorine NIOSH: Pocket Guide to Chemical Hazards - Chlorine Literature References
|
Last Updated Date : 02/13/2026