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BENZOYL PEROXIDE†
| CAS # | 94-36-0 | 
|---|---|
| Formula | 
                               C₁₄H₁₀O₄  | 
          
| Synonyms | 
                               benzoperoxide; dibenzoyl peroxide  | 
          
| Physical description | Colorless to white crystals or a granular powder with a faint, benzaldehyde-like odor. | ||
|---|---|---|---|
| Boiling point | decomposes explosively | Molecular weight | 242.2 | 
| Freezing point/melting point | 217°F | Vapor pressure | <1 mmHg | 
| Flash point | 176°F | Vapor density | |
| Specific gravity | 1.33 | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 1 | NFPA fire rating | 4 | 
| NFPA reactivity rating | 4 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 0335 | 
|---|---|
| Sampling group | |
| Sampler/Sampling media | PTFE filter, 1 µm [SKC 225-2705] | 
| Sampling time* | |
| Sampling volume (TWA)* | 40 L -400 L  | 
                                    
| Sampling flow rate (TWA)* | 1-3 L/min  | 
                                    
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | HPLC-UV | 
| Method reference | NIOSH 5009 (OSHA modified) | 
| Notes | Keep samples refrigerated when not in transit. Ship samples overnight with cold-packs as soon as possible.  | 
                                    
| 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 | |
|---|---|
| Bulk Method | 
| Device | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
| 
                              Sampling information  (see manufacturer instructions)  | 
                                          
| 
               
                                  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 | 
                               5 mg/m³  | 
            REL-TWA | 
                               5 mg/m³  | 
            TLV-TWA | PEL-TWA | 
                               5 mg/m³  | 
          |
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation | 
                               N  | 
            Skin notation | 
                               N  | 
            Skin notation | 
                               N  | 
            Skin notation | 
                               N  | 
          
| Notes: | Notes: | 
                              Notes: 
                                             Visit the ACGIH TLV site for specific data  | 
            Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH | 
                               1500 mg/m³  | 
            |||||
| Carcinogenic classifications: IARC-3, TLV-A4 | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
| 
               NOAA: CAMEO Chemicals - Benzoyl peroxide NIOSH: Pocket Guide to Chemical Hazards - Benzoyl peroxide Literature References 
  | 
          
Last Updated Date : 04/02/2024