PAC Database - Detailed Chemical Data
Chemical Identity
| Chemical | CAS# | UN# | Health Code Numbers | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chloroprene; (beta-Chloroprene; Neoprene) | 126-99-8 | 1991 |
17.00
15.01
4.01
11.01
14.02
4.08
7.01
8.00
11.00
4.09
|
|||||||||
| Formula | Synonyms | |||||||||||
| C4H5Cl | CHLOROPRENE, INHIBITED, 1,3-BUTADIENE, 2-CHLORO-, 2-CHLORO-1,3-BUTADIENE, 2-CHLOROBUTA-1,3-DIENE, 2-CHLOROBUTADIENE, BETA-CHLOROPRENE, CHLOROBUTADIENE, CHLOROPRENE, CHLOROPRÈNE, STABILISÉ (DOT FRENCH), CHLOROPRENE, UNINHIBITED, CLOROPRENO, INHIBIDO (DOT SPANISH), NEOPRENE, UN 1991 | |||||||||||
Physical Properties
| Mol Wt | State | MP (°C) | BP (°C) | VP (Hg) | VP (°C) | SG | LEL (ppm) |
|---|---|---|---|---|---|---|---|
| 88.54 | L | -130 | 59.4 | 75 | 0.3 | .956 @ 20°C | 19000 |
PAC Values
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 3.0 | 67 | 400 |
| PAC-1 | PAC-2 | PAC-3 |
|---|---|---|
| 11 | 240 | 1400 |
Technical Basis
A review of available sources identified several exposure limits for chloroprene: TWAs (PEL, TLV), REL-C, and an IDLH. Data sources were selected according to the hierarchy listed in Table 3.1. The IDLH (1990) was selected as the TEEL-3. The reported REL-C (1 ppm) was evaluated as a TEEL-2, but it was rejected for two reasons: 1) this ceiling was developed for chronic exposure (see CDC reference), and 2) it would result in a TEEL-2 equal the TLV-TWA (1 ppm), violating TEEL development guidelines in Section 3.4.2. Instead, the TEEL-2 was derived according to Table 3.5. The TLV-TWA was selected as the TEEL-1 basis.
• TEEL-1 = TLV-TWA (1 ppm) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990, 400 ppm)
The current TEEL-3 is consistent with Rev. 29A. The Rev. 29A and current TEEL-2 were derived using the same methodology, derived from the TEEL-3; differences in units of mg/m3 may be due to rounding. The Rev. 29A and current TEEL-1 methodology are consistent (TLV-TWA x 3); however, the current value is based on a more current, lower TLV-TWA (2016, 1 ppm).
• TEEL-1 = TLV-TWA (1 ppm) x 3
• TEEL-2 = TEEL-3/6
• TEEL-3 = IDLH (1990, 400 ppm)
The current TEEL-3 is consistent with Rev. 29A. The Rev. 29A and current TEEL-2 were derived using the same methodology, derived from the TEEL-3; differences in units of mg/m3 may be due to rounding. The Rev. 29A and current TEEL-1 methodology are consistent (TLV-TWA x 3); however, the current value is based on a more current, lower TLV-TWA (2016, 1 ppm).
References
CDC. https://www.cdc.gov/niosh/idlh/126998.html
https://www.osha.gov/chemicaldata/188