Chlorine is reported in EPA TSCA Inventory. Community Right-To-Know List. EPA Extremely Hazardous Substances List.

OSHA PEL: TWA 0.5 ppm; STEL 1 ppm
ACGIH TLV: TWA 0.5 ppm; STEL 1 ppm; Not Classifiable as a Human Carcinogen
DFG MAK: 0.5 ppm (1.5 mg/m³)
NIOSH REL: (Chlorine) CL 0.5 ppm/15M
DOT Classification:  2.3; Label: Poison Gas

For occupational chemical analysis use OSHA: #ID-101 or NIOSH: Bromine and Chloride, 6011.

The IUPAC name of Chlorine is molecular chlorine. With the CAS registry number 7782-50-5, it is also named as Bertholite. The product's categories are Inorganics; Chemical Synthesis; Compressed and Liquefied Gases; Synthetic Reagents. Besides, it is light greenish-yellow gas with an irritating odour, which should be sealed in a cool, ventilated place. Chlorine gas reacts with most organic compounds, and will even sluggishly support the combustion of hydrocarbons. In addition, its molecular formula is Cl₂ and molecular weight is 70.91.

The other characteristics of this product can be summarized as: (1)EINECS: 231-959-5; (2)ACD/LogP: 1.85; (3)# of Rule of 5 Violations: 0; (4)ACD/LogD (pH 5.5): 1.85; (5)ACD/LogD (pH 7.4): 1.85; (6)ACD/BCF (pH 5.5): 14.98; (7)ACD/BCF (pH 7.4): 14.98; (8)#H bond acceptors: 0; (9)#H bond donors: 0; (10)#Freely Rotating Bonds: 0; (11)Index of Refraction: 1.375; (12)Molar Refractivity: 11.74 cm³; (13)Molar Volume: 51.3 cm³; (14)Polarizability: 4.65×10^-24cm³; (15)Surface Tension: 20.4 dyne/cm; (16)Density: 1.382 g/cm³; (17)Melting point: -101 °C; (18)Enthalpy of Vaporization: 20.41 kJ/mol; (19)Boiling Point: -34 °C; (20)Water solubility: 0.7 g/100 mL; (21)Vapour Pressure: 6450 mmHg at 25 °C.

Preparation of Chlorine: this chemical can be prepared by the electrolysis of sodium chloride dissolved in water in industry.
2 NaCl + 2 H₂O → Cl₂ + H₂ + 2 NaOH

Uses of Chlorine: this chemical is used in making plastics, solvents for dry cleaning and metal degreasing, textiles, agrochemicals and pharmaceuticals, insecticides, dyestuffs, household cleaning products, etc. And it is an important chemical for water purification (such as water treatment plants), in disinfectants, and in bleach. Moreover, it can be used (in the form of hypochlorous acid) to kill bacteria and other microbes in drinking water supplies and public swimming pools. It has been used extensively in organic and inorganic chemistry as an oxidizing agent and in substitution reactions. It is also used in the production of chlorates and in bromine extraction.

When you are using this chemical, please be cautious about it as the following: it is toxic by inhalation, so please keep container in a well-ventilated place. It also irritates to eyes, respiratory system and skin. In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible). Moreover, it is very toxic to aquatic organisms. You should avoid release to the environment., and refer to special instructions / safety data sheets.

People can use the following data to convert to the molecule structure.
(1)Canonical SMILES: ClCl
(2)InChI: InChI=1S/Cl2/c1-2
(3)InChIKey: KZBUYRJDOAKODT-UHFFFAOYSA-N 

The toxicity data is as follows: