Reported in EPA TSCA Inventory.

Hazard Codes: F, Xn
Risk Statements: 11-21/22-65 
R11:Highly flammable. 
R21/22:Harmful in contact with skin and if swallowed. 
R65:Harmful: may cause lung damage if swallowed.
Safety Statements: 16-29-33-36/37 
S16:Keep away from sources of ignition. 
S29:Do not empty into drains. 
S33:Take precautionary measures against static discharges. 
S36/37:Wear suitable protective clothing and gloves.
RIDADR: UN 2256 3/PG 2
WGK Germany: 1
RTECS: GW2500000
HazardClass: 3
PackingGroup: II
Moderately toxic by inhalation and ingestion. A very dangerous fire hazard when exposed to flame; can react with oxidizers. Dangerous; keep away from heat and open flame. To fight fire, use foam, CO₂, dry chemical.

OSHA PEL: 300 ppm
ACGIH TLV: 300 ppm
DFG MAK: 300 ppm (1000 mg/m³)
DOT Classification:  3; Label: Flammable Liquid

For occupational chemical analysis use NIOSH: Hydrocarbons.

The Cyclohexene ,with the CAS registry number 110-83-8,is also named as 1,2,3,4-Tetrahydrobenzene ; Hexanaphthylene ; NSC 24835 ; Tetrahydrobenzene .It is a colourless liquid. It is insoluble in water. Inhalation of high concentrations may have a narcotic effect. Cyclohexene is highly flammable. And it may react vigorously with strong oxidizing agents. May react exothermically with reducing agents to release hydrogen gas. In the presence of various catalysts (such as acids) or initiators, may undergo exothermic addition polymerization reactions. Oxidizes readily in air to form unstable peroxides that may explode spontaneously. May cause toxic effects if inhaled or absorbed through skin. Inhalation or contact with material may irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. Will be easily ignited by heat, sparks or flames. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor of Cyclohexene explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. It  may explode when heated.It can be used as solvents, and also used in organic synthesis.

Physical properties about Cyclohexene  are:
(1)ACD/LogP:  2.918; (2)# of Rule of 5 Violations:  0; (3)ACD/LogD (pH 5.5):  2.92; (4)ACD/LogD (pH 7.4):  2.92; (5)ACD/BCF (pH 5.5):  97.23; (6)ACD/BCF (pH 7.4):  97.23; (7)ACD/KOC (pH 5.5):  921.49; (8)ACD/KOC (pH 7.4):  921.49; (9)#H bond acceptors:  0; (10)#H bond donors:  0; (11)#Freely Rotating Bonds:  0; (12)Index of Refraction:  1.459; (13)Molar Refractivity:  27.274 cm3; (14)Molar Volume:  99.748 cm3; (15)Surface Tension:  29.0799999237061 dyne/cm; (16)Density:  0.823 g/cm3; (17)Flash Point:  -12.222 °C; (18)Enthalpy of Vaporization:  30.46 kJ/mol; (19)Boiling Point:  85.636 °C at 760 mmHg; (20)Vapour Pressure:  77.0210037231445 mmHg at 25°C.

You can still convert the following datas into molecular structure:
(1)SMILES:C1CCC=CC1;
(2)Std. InChI:InChI=1S/C6H10/c1-2-4-6-5-3-1/h1-2H,3-6H2;
(3)Std. InChIKey:HGCIXCUEYOPUTN-UHFFFAOYSA-N.

Preparation of Cyclohexene:
A common experiment for beginning organic chemistry students is the acid catalyzed dehydration of cyclohexanol with distillative removal of the resulting cyclohexene from the reaction mixture:


Safety Information of Cyclohexenen:
The Cyclohexene is highly flammable. So it should be Keep away from sources of ignition.And it is harmful in contact with skin and if swallowed. When you use it ,wear suitable protective clothing and gloves. Take precautionary measures against static discharges. It is dangers to the environment,so do not empty into drains.

The toxicity data of Cyclohexene as follows: