Datasets:

referencesource
/

workplace-exposure-limits

also_reported listlengths 1 7 ⌀	cas_number stringlengths 5 46 ⌀	disagreements listlengths 0 2 ⌀	id stringlengths 3 80	pel_mgm3 stringlengths 1 11 ⌀	pel_ppm stringclasses 46 values	source stringlengths 39 79	source_quote stringlengths 19 139	substance stringlengths 3 110	url stringlengths 58 135	verified_fields listlengths 2 7	rel_statement stringclasses 21 values	rel_mgm3 stringclasses 81 values	rel_ppm stringclasses 37 values	ceiling stringclasses 6 values	stel_mgm3 stringclasses 32 values	stel_ppm stringclasses 19 values
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0595.html", "source_quote": "NIOSH REL TWA 500 ppm (4170 mg/m3)", "value": "TWA 500" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/n...	76-11-9	[]	1-1-1-2-tetrachloro-2-2-difluoroethane	4170	500	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1,1,2-Tetrachloro-2,2-difluoroethane \| 76-11-9 \| 500 \| 4170 \| - \|	1,1,1,2-Tetrachloro-2,2-difluoroethane	https://referencesource.org/workplace-exposure-limits/1-1-1-2-tetrachloro-2-2-difluoroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	630-20-6	null	1-1-1-2-tetrachloroethane	null	null	https://www.cdc.gov/niosh/npg/npgd0597.html	NIOSH REL Handle with caution in the workplace. See Appendix C (Chloroethanes)	1,1,1,2-Tetrachloroethane	https://referencesource.org/workplace-exposure-limits/1-1-1-2-tetrachloroethane/	[ "cas_number", "rel_statement", "substance" ]	Handle with caution in the workplace. See Appendix C (Chloroethanes)	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0596.html", "source_quote": "NIOSH REL TWA 500 ppm (4170 mg/m3)", "value": "TWA 500" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/n...	76-12-0	[]	1-1-2-2-tetrachloro-1-2-difluoroethane	4170	500	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1,2,2-Tetrachloro-1,2-difluoroethane \| 76-12-0 \| 500 \| 4170 \| - \|	1,1,2,2-Tetrachloro-1,2-difluoroethane	https://referencesource.org/workplace-exposure-limits/1-1-2-2-tetrachloro-1-2-difluoroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0598.html", "source_quote": "NIOSH REL Ca TWA 1 ppm (7 mg/m3) [skin]", "value": "TWA 1" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/nios...	79-34-5	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "1,1,2,2-Tetrachloroethane \| 79-34-5 \| 5 \| 35 \| X \|", "value": "5" }, { ...	1-1-2-2-tetrachloroethane	35	5	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1,2,2-Tetrachloroethane \| 79-34-5 \| 5 \| 35 \| X \|	1,1,2,2-Tetrachloroethane	https://referencesource.org/workplace-exposure-limits/1-1-2-2-tetrachloroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "76131 \| \| 1,1,2-Trichloro-1,2,2-trifluoroethane \| 1000 \| 7600 \| 2000 ppm \| 1250 \| 9500", "value": "2000 ppm" }, { "as_of": "2026-08-05T00:00:00", "field": "stel...	76-13-1	[]	1-1-2-trichloro-1-2-2-trifluoroethane	7600	1000	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1,2-Trichloro-1,2,2-trifluoroethane \| 76-13-1 \| 1000 \| 7600 \| - \|	1,1,2-Trichloro-1,2,2-trifluoroethane	https://referencesource.org/workplace-exposure-limits/1-1-2-trichloro-1-2-2-trifluoroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0628.html", "source_quote": "NIOSH REL Ca TWA 10 ppm (45 mg/m3) [skin]", "value": "TWA 10" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	79-00-5	[]	1-1-2-trichloroethane	45	10	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1,2-Trichloroethane \| 79-00-5 \| 10 \| 45 \| X \|	1,1,2-Trichloroethane	https://referencesource.org/workplace-exposure-limits/1-1-2-trichloroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0198.html", "source_quote": "NIOSH REL TWA 2 ppm (10 mg/m3)", "value": "TWA 2" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npg...	594-72-9	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "1,1-Dichloro-1-nitroethane \| 594-72-9 \| (C)10 \| (C)60 \| - \|", "value": "(C)10" }, ...	1-1-dichloro-1-nitroethane	(C)60	(C)10	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1-Dichloro-1-nitroethane \| 594-72-9 \| (C)10 \| (C)60 \| - \|	1,1-Dichloro-1-nitroethane	https://referencesource.org/workplace-exposure-limits/1-1-dichloro-1-nitroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0194.html", "source_quote": "NIOSH REL TWA 100 ppm (400 mg/m3)", "value": "TWA 100" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/np...	75-34-3	[]	1-1-dichloroethane	400	100	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1-Dichloroethane \| 75-34-3 \| 100 \| 400 \| - \|	1,1-Dichloroethane	https://referencesource.org/workplace-exposure-limits/1-1-dichloroethane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0227.html", "source_quote": "NIOSH REL Ca C 0.06 ppm (0.15 mg/m3) [2-hr]", "value": "C 0.06" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov...	57-14-7	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "1,1-Dimethylhydrazine \| 57-14-7 \| 0.5 \| 1 \| X \|", "value": "0.5" }, { ...	1-1-dimethylhydrazine	1	0.5	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,1-Dimethylhydrazine \| 57-14-7 \| 0.5 \| 1 \| X \|	1,1-Dimethylhydrazine	https://referencesource.org/workplace-exposure-limits/1-1-dimethylhydrazine/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0631.html", "source_quote": "NIOSH REL Ca TWA 10 ppm (60 mg/m3) [skin]", "value": "TWA 10" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	96-18-4	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "1,2,3-Trichloropropane \| 96-18-4 \| 50 \| 300 \| - \|", "value": "50" }, { ...	1-2-3-trichloropropane	300	50	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,2,3-Trichloropropane \| 96-18-4 \| 50 \| 300 \| - \|	1,2,3-Trichloropropane	https://referencesource.org/workplace-exposure-limits/1-2-3-trichloropropane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	526-73-8	null	1-2-3-trimethylbenzene	null	null	https://www.cdc.gov/niosh/npg/npgd0637.html	NIOSH REL TWA 25 ppm (125 mg/m3)	1,2,3-Trimethylbenzene	https://referencesource.org/workplace-exposure-limits/1-2-3-trimethylbenzene/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	125	TWA 25	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0627.html", "source_quote": "NIOSH REL C 5 ppm (40 mg/m3)", "value": "C 5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd062...	120821	[]	1-2-4-trichlorobenzene	40	5	https://www.dir.ca.gov/title8/5155.html	120821 \| \| 1,2,4-Trichlorobenzene \| 5 \| 40 \| C	1,2,4-Trichlorobenzene	https://referencesource.org/workplace-exposure-limits/1-2-4-trichlorobenzene/	[ "cas_number", "ceiling", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	C	null	null
null	95-63-6	null	1-2-4-trimethylbenzene	null	null	https://www.cdc.gov/niosh/npg/npgd0638.html	NIOSH REL TWA 25 ppm (125 mg/m3)	1,2,4-Trimethylbenzene	https://referencesource.org/workplace-exposure-limits/1-2-4-trimethylbenzene/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	125	TWA 25	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "96128 \| \| 1,2-Dibromo-3-chloropropane; DBCP; see Section 5212 \| .001 \| .01", "value": ".001" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "sour...	96-12-8	[]	1-2-dibromo-3-chloropropane	null	null	https://www.cdc.gov/niosh/npg/npgd0184.html	NIOSH REL Ca See Appendix A	1,2-Dibromo-3-chloropropane	https://referencesource.org/workplace-exposure-limits/1-2-dibromo-3-chloropropane/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0195.html", "source_quote": "NIOSH REL TWA 200 ppm (790 mg/m3)", "value": "TWA 200" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/np...	540-59-0	[]	1-2-dichloroethylene	790	200	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,2-Dichloroethylene \| 540-59-0 \| 200 \| 790 \| - \|	1,2-Dichloroethylene	https://referencesource.org/workplace-exposure-limits/1-2-dichloroethylene/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0201.html", "source_quote": "NIOSH REL TWA 1000 ppm (7000 mg/m3)", "value": "TWA 1000" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh...	76142	[]	1-2-dichlorotetrafluoroethane-fluorocarbon-114	7,000	1,000	https://www.dir.ca.gov/title8/5155.html	76142 \| \| 1,2-Dichlorotetrafluoroethane; Fluorocarbon 114 \| 1,000 \| 7,000	1,2-Dichlorotetrafluoroethane; Fluorocarbon 114	https://referencesource.org/workplace-exposure-limits/1-2-dichlorotetrafluoroethane-fluorocarbon-114/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	2451629	null	1-3-5-triglycidyl-s-triazinetrione	0.005	null	https://www.dir.ca.gov/title8/5155.html	2451629 \| \| 1,3,5-Triglycidyl-s-triazinetrione \| \| 0.005	1,3,5-Triglycidyl-s-triazinetrione	https://referencesource.org/workplace-exposure-limits/1-3-5-triglycidyl-s-triazinetrione/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
null	108-67-8	[]	1-3-5-trimethylbenzene	null	null	https://www.cdc.gov/niosh/npg/npgd0639.html	NIOSH REL TWA 25 ppm (125 mg/m3)	1,3,5-Trimethylbenzene	https://referencesource.org/workplace-exposure-limits/1-3-5-trimethylbenzene/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	125	TWA 25	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "106990 \| \| 1,3-Butadiene (see also section 5201) \| 1 \| 2.2 \| \| 5 \| 11", "value": "1" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "ht...	106-99-0	[]	1-3-butadiene	null	null	https://www.cdc.gov/niosh/npg/npgd0067.html	NIOSH REL Ca See Appendix A	1,3-Butadiene	https://referencesource.org/workplace-exposure-limits/1-3-butadiene/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "stel_mgm3", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "118525 \| \| 1,3-Dichloro-5,5-dimethyl hydantoin \| -- \| 0.2 \| \| -- \| 0.4", "value": "0.4" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source"...	118-52-5	[]	1-3-dichloro-5-5-dimethyl-hydantoin	0.2	null	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1,3-Dichloro-5,5-dimethyl hydantoin \| 118-52-5 \| - \| 0.2 \| - \|	1,3-Dichloro-5,5-dimethyl hydantoin	https://referencesource.org/workplace-exposure-limits/1-3-dichloro-5-5-dimethyl-hydantoin/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "542756 \| S \| Dichloropropene \| 1 \| 5", "value": "1" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.ca.gov/title8/5155....	542-75-6	[]	1-3-dichloropropene	null	null	https://www.cdc.gov/niosh/npg/npgd0199.html	NIOSH REL Ca TWA 1 ppm (5 mg/m3) [skin]	1,3-Dichloropropene	https://referencesource.org/workplace-exposure-limits/1-3-dichloropropene/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	5	TWA 1	null	null	null
null	764410	null	1-4-dichloro-2-butene	0.025	0.005	https://www.dir.ca.gov/title8/5155.html	764410 \| S \| 1,4-Dichloro-2-butene \| 0.005 \| 0.025	1,4-Dichloro-2-butene	https://referencesource.org/workplace-exposure-limits/1-4-dichloro-2-butene/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	124094	null	1-6-hexanediamine	2.3	0.5	https://www.dir.ca.gov/title8/5155.html	124094 \| \| 1,6-Hexanediamine \| 0.5 \| 2.3	1,6-Hexanediamine	https://referencesource.org/workplace-exposure-limits/1-6-hexanediamine/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	106945	null	1-bromopropane-n-propyl-bromide	25	5	https://www.dir.ca.gov/title8/5155.html	106945 \| S \| 1-bromopropane, n-propyl bromide \| 5 \| 25	1-bromopropane, n-propyl bromide	https://referencesource.org/workplace-exposure-limits/1-bromopropane-n-propyl-bromide/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0130.html", "source_quote": "NIOSH REL TWA 2 ppm (10 mg/m3)", "value": "TWA 2" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npg...	600-25-9	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "1-Chloro-1-nitropropane \| 600-25-9 \| 20 \| 100 \| - \|", "value": "20" }, { ...	1-chloro-1-nitropropane	100	20	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1-Chloro-1-nitropropane \| 600-25-9 \| 20 \| 100 \| - \|	1-Chloro-1-nitropropane	https://referencesource.org/workplace-exposure-limits/1-chloro-1-nitropropane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	143-10-2	null	1-decanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0176.html	NIOSH REL C 0.5 ppm (3.6 mg/m3) [15-minute]	1-Decanethiol	https://referencesource.org/workplace-exposure-limits/1-decanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	3.6	C 0.5	null	null	null
null	112-55-0	null	1-dodecanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0249.html	NIOSH REL C 0.5 ppm (4.1 mg/m3) [15-minute]	1-Dodecanethiol	https://referencesource.org/workplace-exposure-limits/1-dodecanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	4.1	C 0.5	null	null	null
null	1639-09-4	null	1-heptanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0313.html	NIOSH REL C 0.5 ppm (2.7 mg/m3) [15-minute]	1-Heptanethiol	https://referencesource.org/workplace-exposure-limits/1-heptanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	2.7	C 0.5	null	null	null
null	2917-26-2	null	1-hexadecanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0318.html	NIOSH REL C 0.5 ppm (5.3 mg/m3) [15-minute]	1-Hexadecanethiol	https://referencesource.org/workplace-exposure-limits/1-hexadecanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	5.3	C 0.5	null	null	null
null	592416	null	1-hexene	180	50	https://www.dir.ca.gov/title8/5155.html	592416 \| \| 1-Hexene \| 50 \| 180	1-Hexene	https://referencesource.org/workplace-exposure-limits/1-hexene/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0459.html", "source_quote": "NIOSH REL TWA 25 ppm (90 mg/m3)", "value": "TWA 25" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/n...	108-03-2	[]	1-nitropropane	90	25	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	1-Nitropropane \| 108-03-2 \| 25 \| 90 \| - \|	1-Nitropropane	https://referencesource.org/workplace-exposure-limits/1-nitropropane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	1455-21-6	null	1-nonanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0467.html	NIOSH REL C 0.5 ppm (3.3 mg/m3) [15-minute]	1-Nonanethiol	https://referencesource.org/workplace-exposure-limits/1-nonanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	3.3	C 0.5	null	null	null
null	2885-00-9	null	1-octadecanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0469.html	NIOSH REL C 0.5 ppm (5.9 mg/m3) [15-minute]	1-Octadecanethiol	https://referencesource.org/workplace-exposure-limits/1-octadecanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	5.9	C 0.5	null	null	null
null	111-88-6	null	1-octanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0471.html	NIOSH REL C 0.5 ppm (3.0 mg/m3) [15-minute]	1-Octanethiol	https://referencesource.org/workplace-exposure-limits/1-octanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	3.0	C 0.5	null	null	null
null	110-66-7	null	1-pentanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0487.html	NIOSH REL C 0.5 ppm (2.1 mg/m3) [15-minute]	1-Pentanethiol	https://referencesource.org/workplace-exposure-limits/1-pentanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	2.1	C 0.5	null	null	null
null	107-03-9	null	1-propanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0526.html	NIOSH REL C 0.5 ppm (1.6 mg/m3) [15-minute]	1-Propanethiol	https://referencesource.org/workplace-exposure-limits/1-propanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	1.6	C 0.5	null	null	null
null	5332-52-5	null	1-undecanethiol	null	null	https://www.cdc.gov/niosh/npg/npgd0649.html	NIOSH REL C 0.5 ppm (3.9 mg/m3) [15-minute]	1-Undecanethiol	https://referencesource.org/workplace-exposure-limits/1-undecanethiol/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	3.9	C 0.5	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0200.html", "source_quote": "NIOSH REL TWA 1 ppm (6 mg/m3)", "value": "TWA 1" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd...	75990	[]	2-2-dichloropropionic-acid	6	1	https://www.dir.ca.gov/title8/5155.html	75990 \| \| 2,2-Dichloropropionic acid \| 1 \| 6	2,2-Dichloropropionic acid	https://referencesource.org/workplace-exposure-limits/2-2-dichloropropionic-acid/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	1746-01-6	null	2-3-7-8-tetrachloro-dibenzo-p-dioxin	null	null	https://www.cdc.gov/niosh/npg/npgd0594.html	NIOSH REL Ca See Appendix A	2,3,7,8-Tetrachloro-dibenzo-p-dioxin	https://referencesource.org/workplace-exposure-limits/2-3-7-8-tetrachloro-dibenzo-p-dioxin/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2,4,5-T (2,4,5-trichlorophenoxyacetic acid) \| 93-76-5 \| - \| 10 \| - \|", "value": "10" } ]	93-76-5	[]	2-4-5-t	null	null	https://www.cdc.gov/niosh/npg/npgd0583.html	NIOSH REL TWA 10 mg/m3	2,4,5-T	https://referencesource.org/workplace-exposure-limits/2-4-5-t/	[ "cas_number", "rel_mgm3", "substance" ]	null	TWA 10	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2,4,6-Trinitrotoluene (TNT) \| 118-96-7 \| - \| 1.5 \| X \|", "value": "1.5" } ]	118-96-7	[]	2-4-6-trinitrotoluene	null	null	https://www.cdc.gov/niosh/npg/npgd0641.html	NIOSH REL TWA 0.5 mg/m3 [skin]	2,4,6-Trinitrotoluene	https://referencesource.org/workplace-exposure-limits/2-4-6-trinitrotoluene/	[ "cas_number", "rel_mgm3", "substance" ]	null	TWA 0.5	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "94757 \| \| 2,4-D;2,4-dichlorophenoxyacetic acid \| -- \| 10", "value": "10" } ]	94-75-7	[]	2-4-d	null	null	https://www.cdc.gov/niosh/npg/npgd0173.html	NIOSH REL TWA 10 mg/m3	2,4-D	https://referencesource.org/workplace-exposure-limits/2-4-d/	[ "cas_number", "rel_mgm3", "substance" ]	null	TWA 10	null	null	null	null
null	615-05-4	null	2-4-diaminoanisole-and-its-salts	null	null	https://www.cdc.gov/niosh/npg/npgd0179.html	NIOSH REL Ca Minimize occupational exposure (especially skin exposures) See Appendix A	2,4-Diaminoanisole (and its salts)	https://referencesource.org/workplace-exposure-limits/2-4-diaminoanisole-and-its-salts/	[ "cas_number", "rel_statement", "substance" ]	Ca Minimize occupational exposure (especially skin exposures) See Appendix A	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0235.html", "source_quote": "NIOSH REL Ca TWA 1.5 mg/m3 [skin]", "value": "TWA 1.5" } ]	25321146	[ { "field": "pel_mgm3", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "25321146 \| S \| 2,4-Dinitrotoluene \| -- \| 0.15", "value": "0.15" }, { "as_of": "2026-08-05T00:00:00", ...	2-4-dinitrotoluene	0.15	null	https://www.dir.ca.gov/title8/5155.html	25321146 \| S \| 2,4-Dinitrotoluene \| -- \| 0.15	2,4-Dinitrotoluene	https://referencesource.org/workplace-exposure-limits/2-4-dinitrotoluene/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0246.html", "source_quote": "NIOSH REL TWA 10 mg/m3", "value": "TWA 10" } ]	128370	[]	2-6-di-tert-butyl-p-cresol	10	null	https://www.dir.ca.gov/title8/5155.html	128370 \| \| 2,6-Di-tert-butyl-p-cresol \| -- \| 10	2,6-Di-tert-butyl-p-cresol	https://referencesource.org/workplace-exposure-limits/2-6-di-tert-butyl-p-cresol/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
null	53-96-3	[]	2-acetylaminofluorene	null	null	https://www.cdc.gov/niosh/npg/npgd0007.html	NIOSH REL Ca See Appendix A	2-Acetylaminofluorene	https://referencesource.org/workplace-exposure-limits/2-acetylaminofluorene/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0026.html", "source_quote": "NIOSH REL TWA 0.5 ppm (2 mg/m3)", "value": "TWA 0.5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/...	504-29-0	[]	2-aminopyridine	2	0.5	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	2-Aminopyridine \| 504-29-0 \| 0.5 \| 2 \| - \|	2-Aminopyridine	https://referencesource.org/workplace-exposure-limits/2-aminopyridine/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2-Butanone (Methyl ethyl ketone) \| 78-93-3 \| 200 \| 590 \| - \|", "value": "200" }, { "as_of": "2026-08-05T00:00:00", "fiel...	78-93-3	[]	2-butanone	null	null	https://www.cdc.gov/niosh/npg/npgd0069.html	NIOSH REL TWA 200 ppm (590 mg/m3) ST 300 ppm (885 mg/m3)	2-Butanone	https://referencesource.org/workplace-exposure-limits/2-butanone/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	590	TWA 200	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0070.html", "source_quote": "NIOSH REL TWA 5 ppm (24 mg/m3) [skin]", "value": "TWA 5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/...	111-76-2	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2-Butoxyethanol \| 111-76-2 \| 50 \| 240 \| X \|", "value": "50" }, { "as_o...	2-butoxyethanol	240	50	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	2-Butoxyethanol \| 111-76-2 \| 50 \| 240 \| X \|	2-Butoxyethanol	https://referencesource.org/workplace-exposure-limits/2-butoxyethanol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	112-07-2	null	2-butoxyethanol-acetate	null	null	https://www.cdc.gov/niosh/npg/npgd0071.html	NIOSH REL TWA 5 ppm (33 mg/m3)	2-Butoxyethanol acetate	https://referencesource.org/workplace-exposure-limits/2-butoxyethanol-acetate/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	33	TWA 5	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0136.html", "source_quote": "NIOSH REL TWA 10 mg/m3 (total) ST 20 mg/m3 (total) TWA 5 mg/m3 (resp)", "value": "TWA 10 mg/m3 (total) ST 20 mg/m3 (total) TWA 5 mg/m3 (resp)" } ]	1929-82-4	[]	2-chloro-6-trichloromethyl-pyridine	null	null	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	2-Chloro-6-(trichloromethyl) pyridine \| 1929-82-4 \| - \| - \| - \|	2-Chloro-6-(trichloromethyl) pyridine	https://referencesource.org/workplace-exposure-limits/2-chloro-6-trichloromethyl-pyridine/	[ "cas_number", "substance" ]	null	null	null	null	null	null
null	598787	null	2-chloropropionic-acid	0.44	0.1	https://www.dir.ca.gov/title8/5155.html	598787 \| S \| 2-Chloropropionic acid \| 0.1 \| 0.44	2-Chloropropionic acid	https://referencesource.org/workplace-exposure-limits/2-chloropropionic-acid/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0210.html", "source_quote": "NIOSH REL TWA 10 ppm (50 mg/m3) [skin]", "value": "TWA 10" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/nios...	100378	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "100378 \| S \| 2-(Diethylamino) ethanol \| 2 \| 9.6", "value": "2" }, { "as_of": "2026-08-05T00:00:00", "s...	2-diethylamino-ethanol	9.6	2	https://www.dir.ca.gov/title8/5155.html	100378 \| S \| 2-(Diethylamino) ethanol \| 2 \| 9.6	2-(Diethylamino) ethanol	https://referencesource.org/workplace-exposure-limits/2-diethylamino-ethanol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0258.html", "source_quote": "NIOSH REL TWA 0.5 ppm (1.8 mg/m3) [skin]", "value": "TWA 0.5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	110805	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "110805 \| S \| 2-Ethoxyethanol \| 5 \| 18", "value": "5" }, { "as_of": "2026-08-05T00:00:00", "source": "h...	2-ethoxyethanol	18	5	https://www.dir.ca.gov/title8/5155.html	110805 \| S \| 2-Ethoxyethanol \| 5 \| 18	2-Ethoxyethanol	https://referencesource.org/workplace-exposure-limits/2-ethoxyethanol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0259.html", "source_quote": "NIOSH REL TWA 0.5 ppm (2.7 mg/m3) [skin]", "value": "TWA 0.5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	111159	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "111159 \| S \| 2-Ethoxyethyl acetate \| 5 \| 27", "value": "5" }, { "as_of": "2026-08-05T00:00:00", "sourc...	2-ethoxyethyl-acetate	27	5	https://www.dir.ca.gov/title8/5155.html	111159 \| S \| 2-Ethoxyethyl acetate \| 5 \| 27	2-Ethoxyethyl acetate	https://referencesource.org/workplace-exposure-limits/2-ethoxyethyl-acetate/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2-Hexanone (Methyl n-butyl ketone) \| 591-78-6 \| 100 \| 410 \| - \|", "value": "100" }, { "as_of": "2026-08-05T00:00:00", "f...	591-78-6	[]	2-hexanone	null	null	https://www.cdc.gov/niosh/npg/npgd0325.html	NIOSH REL TWA 1 ppm (4 mg/m3)	2-Hexanone	https://referencesource.org/workplace-exposure-limits/2-hexanone/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	4	TWA 1	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0339.html", "source_quote": "NIOSH REL TWA 0.5 ppm (3 mg/m3) [skin]", "value": "TWA 0.5" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/nio...	999611	[]	2-hydroxypropyl-acrylate	3	0.5	https://www.dir.ca.gov/title8/5155.html	999611 \| S \| 2-Hydroxypropyl acrylate \| 0.5 \| 3	2-Hydroxypropyl acrylate	https://referencesource.org/workplace-exposure-limits/2-hydroxypropyl-acrylate/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "109591 \| \| Isopropoxyethanol \| 25 \| 105", "value": "25" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.ca.gov/title8/5...	109-59-1	[]	2-isopropoxyethanol	null	null	https://www.cdc.gov/niosh/npg/npgd0357.html	NIOSH REL See Appendix D	2-Isopropoxyethanol	https://referencesource.org/workplace-exposure-limits/2-isopropoxyethanol/	[ "cas_number", "rel_statement", "substance" ]	See Appendix D	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0401.html", "source_quote": "NIOSH REL TWA 0.1 ppm (0.3 mg/m3) [skin]", "value": "TWA 0.1" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	109864	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "109864 \| S \| 2-Methoxyethanol \| 5 \| 16", "value": "5" }, { "as_of": "2026-08-05T00:00:00", "source": "...	2-methoxyethanol	16	5	https://www.dir.ca.gov/title8/5155.html	109864 \| S \| 2-Methoxyethanol \| 5 \| 16	2-Methoxyethanol	https://referencesource.org/workplace-exposure-limits/2-methoxyethanol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0402.html", "source_quote": "NIOSH REL TWA 0.1 ppm (0.5 mg/m3) [skin]", "value": "TWA 0.1" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/n...	110496	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "110496 \| \| 2-Methoxyethyl acetate \| 5 \| 24", "value": "5" }, { "as_of": "2026-08-05T00:00:00", "source...	2-methoxyethyl-acetate	24	5	https://www.dir.ca.gov/title8/5155.html	110496 \| \| 2-Methoxyethyl acetate \| 5 \| 24	2-Methoxyethyl acetate	https://referencesource.org/workplace-exposure-limits/2-methoxyethyl-acetate/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	624419	null	2-methylbutyl-acetate-see-pentyl-acetate	null	null	https://www.dir.ca.gov/title8/5155.html	624419 \| \| 2-Methylbutyl acetate; see Pentyl acetate	2-Methylbutyl acetate; see Pentyl acetate	https://referencesource.org/workplace-exposure-limits/2-methylbutyl-acetate-see-pentyl-acetate/	[ "cas_number", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0409.html", "source_quote": "NIOSH REL TWA 0.2 mg/m3 [skin]", "value": "TWA 0.2" } ]	12108133	[]	2-methylcyclopentadienyl-manganese-tricarbonyl-as-mn	0.2	null	https://www.dir.ca.gov/title8/5155.html	12108133 \| S \| 2-Methylcyclopentadienyl manganese tricarbonyl, as Mn \| -- \| 0.2	2-Methylcyclopentadienyl manganese tricarbonyl, as Mn	https://referencesource.org/workplace-exposure-limits/2-methylcyclopentadienyl-manganese-tricarbonyl-as-mn/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0185.html", "source_quote": "NIOSH REL TWA 2 ppm (14 mg/m3) [skin]", "value": "TWA 2" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/...	102818	[]	2-n-dibutylaminoethanol	14	2	https://www.dir.ca.gov/title8/5155.html	102818 \| S \| 2-N-Dibutylaminoethanol \| 2 \| 14	2-N-Dibutylaminoethanol	https://referencesource.org/workplace-exposure-limits/2-n-dibutylaminoethanol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	581-89-5	null	2-nitronaphthalene	null	null	https://www.cdc.gov/niosh/npg/npgd0458.html	NIOSH REL Ca* See Appendix A	2-Nitronaphthalene	https://referencesource.org/workplace-exposure-limits/2-nitronaphthalene/	[ "cas_number", "rel_statement", "substance" ]	Ca* See Appendix A	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0460.html", "source_quote": "NIOSH REL Ca See Appendix A", "value": "Ca See Appendix A" } ]	79-46-9	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2-Nitropropane \| 79-46-9 \| 25 \| 90 \| - \|", "value": "25" }, { "as_of":...	2-nitropropane	90	25	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	2-Nitropropane \| 79-46-9 \| 25 \| 90 \| - \|	2-Nitropropane	https://referencesource.org/workplace-exposure-limits/2-nitropropane/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "2-Pentanone (Methyl propyl ketone) \| 107-87-9 \| 200 \| 700 \| - \|", "value": "200" }, { "as_of": "2026-08-05T00:00:00", "f...	107-87-9	[]	2-pentanone	null	null	https://www.cdc.gov/niosh/npg/npgd0488.html	NIOSH REL TWA 150 ppm (530 mg/m3)	2-Pentanone	https://referencesource.org/workplace-exposure-limits/2-pentanone/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	530	TWA 150	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0191.html", "source_quote": "NIOSH REL Ca See Appendix A", "value": "Ca See Appendix A" } ]	91941	[]	3-3-dichlorobenzidine-4-4-diamino-3-3-dichlorobiphenyl-see-section-5209	null	null	https://www.dir.ca.gov/title8/5155.html	91941 \| S \| 3,3'-Dichlorobenzidine; 4,4'-diamino-3,3'-dichlorobiphenyl; see Section 5209	3,3'-Dichlorobenzidine; 4,4'-diamino-3,3'-dichlorobiphenyl; see Section 5209	https://referencesource.org/workplace-exposure-limits/3-3-dichlorobenzidine-4-4-diamino-3-3-dichlorobiphenyl-see-section-5209/	[ "cas_number", "substance" ]	null	null	null	null	null	null
null	620111	null	3-amyl-acetate-see-pentyl-acetate	null	null	https://www.dir.ca.gov/title8/5155.html	620111 \| \| 3-Amyl acetate; see Pentyl acetate	3-Amyl acetate; see Pentyl acetate	https://referencesource.org/workplace-exposure-limits/3-amyl-acetate-see-pentyl-acetate/	[ "cas_number", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0411.html", "source_quote": "NIOSH REL Ca TWA 0.003 mg/m3 [skin]", "value": "TWA 0.003" } ]	101144	[]	4-4-methylene-bis-2-chloroaniline-see-also-section-5215	0.01	null	https://www.dir.ca.gov/title8/5155.html	101144 \| S \| 4,4′-Methylene bis(2-chloroaniline), see also Section 5215 \| -- \| 0.01	4,4′-Methylene bis(2-chloroaniline), see also Section 5215	https://referencesource.org/workplace-exposure-limits/4-4-methylene-bis-2-chloroaniline-see-also-section-5215/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0415.html", "source_quote": "NIOSH REL Ca See Appendix A", "value": "Ca See Appendix A" } ]	101779	[]	4-4-methylene-dianiline-mda-see-also-sections-1535-5200	0.08	0.01	https://www.dir.ca.gov/title8/5155.html	101779 \| S \| 4,4′-Methylene dianiline; MDA (see also Sections 1535 & 5200) \| 0.01 \| 0.08 \| \| 0.1 \| 0.8	4,4′-Methylene dianiline; MDA (see also Sections 1535 & 5200)	https://referencesource.org/workplace-exposure-limits/4-4-methylene-dianiline-mda-see-also-sections-1535-5200/	[ "cas_number", "pel_mgm3", "pel_ppm", "stel_mgm3", "stel_ppm", "substance" ]	null	null	null	null	0.8	0.1
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0609.html", "source_quote": "NIOSH REL TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp)", "value": "TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp)" } ]	96-69-5	[]	4-4-thiobis-6-tert-butyl-m-cresol	null	null	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	4,4′-Thiobis (6-tert, Butyl-m-cresol) \| 96-69-5 \| - \| - \| - \|	4,4′-Thiobis (6-tert, Butyl-m-cresol)	https://referencesource.org/workplace-exposure-limits/4-4-thiobis-6-tert-butyl-m-cresol/	[ "cas_number", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0234.html", "source_quote": "NIOSH REL TWA 0.2 mg/m3 [skin]", "value": "TWA 0.2" } ]	534521	[]	4-6-dinitro-o-cresol-2-methyl-4-6-dinitrophenol	0.2	null	https://www.dir.ca.gov/title8/5155.html	534521 \| S \| 4,6-Dinitro-o-cresol; 2-methyl-4,6-dinitrophenol \| -- \| 0.2	4,6-Dinitro-o-cresol; 2-methyl-4,6-dinitrophenol	https://referencesource.org/workplace-exposure-limits/4-6-dinitro-o-cresol-2-methyl-4-6-dinitrophenol/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
null	92-67-1	[]	4-aminodiphenyl	null	null	https://www.cdc.gov/niosh/npg/npgd0025.html	NIOSH REL Ca See Appendix A	4-Aminodiphenyl	https://referencesource.org/workplace-exposure-limits/4-aminodiphenyl/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
null	60-11-7	[]	4-dimethylaminoazobenzene	null	null	https://www.cdc.gov/niosh/npg/npgd0220.html	NIOSH REL Ca See Appendix A	4-Dimethylaminoazobenzene	https://referencesource.org/workplace-exposure-limits/4-dimethylaminoazobenzene/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0390.html", "source_quote": "NIOSH REL TWA 5 mg/m3", "value": "TWA 5" } ]	150765	[]	4-methoxyphenol	5	null	https://www.dir.ca.gov/title8/5155.html	150765 \| \| 4-Methoxyphenol \| -- \| 5	4-Methoxyphenol	https://referencesource.org/workplace-exposure-limits/4-methoxyphenol/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
null	92-93-3	[]	4-nitrobiphenyl	null	null	https://www.cdc.gov/niosh/npg/npgd0451.html	NIOSH REL Ca See Appendix A	4-Nitrobiphenyl	https://referencesource.org/workplace-exposure-limits/4-nitrobiphenyl/	[ "cas_number", "rel_statement", "substance" ]	Ca See Appendix A	null	null	null	null	null
null	100403	null	4-vinyl-cyclohexene	0.4	0.1	https://www.dir.ca.gov/title8/5155.html	100403 \| S \| 4-Vinyl cyclohexene \| 0.1 \| 0.4	4-Vinyl cyclohexene	https://referencesource.org/workplace-exposure-limits/4-vinyl-cyclohexene/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Ethyl amyl ketone (5-Methyl-3-heptanone) \| 541-85-5 \| 25 \| 130 \| - \|", "value": "25" }, { "as_of": "2026-08-05T00:00:00", ...	541-85-5	[]	5-methyl-3-heptanone	null	null	https://www.cdc.gov/niosh/npg/npgd0418.html	NIOSH REL TWA 25 ppm (130 mg/m3)	5-Methyl-3-heptanone	https://referencesource.org/workplace-exposure-limits/5-methyl-3-heptanone/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	130	TWA 25	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0119.html", "source_quote": "NIOSH REL TWA 0.3 mg/m3 (0.05 ppm)", "value": "0.05" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/...	532-27-4	[]	a-chloroacetophenone-phenacyl-chloride	0.3	0.05	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	a-Chloroacetophenone (Phenacyl chloride) \| 532-27-4 \| 0.05 \| 0.3 \| - \|	a-Chloroacetophenone (Phenacyl chloride)	https://referencesource.org/workplace-exposure-limits/a-chloroacetophenone-phenacyl-chloride/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "75070 \| \| Acetaldehyde \| 25 \| 45 \| C", "value": "C" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/...	75-07-0	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Acetaldehyde \| 75-07-0 \| 200 \| 360 \| - \|", "value": "200" }, { "as_of"...	acetaldehyde	360	200	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetaldehyde \| 75-07-0 \| 200 \| 360 \| - \|	Acetaldehyde	https://referencesource.org/workplace-exposure-limits/acetaldehyde/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "64197 \| \| Acetic acid \| 10 \| 25 \| 40 ppm \| 15 \| 37", "value": "40 ppm" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://www.dir....	64-19-7	[]	acetic-acid	25	10	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetic acid \| 64-19-7 \| 10 \| 25 \| - \|	Acetic acid	https://referencesource.org/workplace-exposure-limits/acetic-acid/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "108247 \| \| Acetic Anhydride \| 5 \| 20 \| C", "value": "C" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/np...	108-24-7	[]	acetic-anhydride	20	5	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetic anhydride \| 108-24-7 \| 5 \| 20 \| - \|	Acetic anhydride	https://referencesource.org/workplace-exposure-limits/acetic-anhydride/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "67641 \| \| Acetone \| 500 \| 1200 \| 3000 ppm \| 750 \| 1780", "value": "3000 ppm" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://ww...	67-64-1	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Acetone \| 67-64-1 \| 1000 \| 2400 \| - \|", "value": "1000" }, { "as_of": ...	acetone	2400	1000	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetone \| 67-64-1 \| 1000 \| 2400 \| - \|	Acetone	https://referencesource.org/workplace-exposure-limits/acetone/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "75865 \| \| Acetone cyanohydrin as CN \| 4.7 \| 5 \| C", "value": "4.7" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.ca.g...	75-86-5	[]	acetone-cyanohydrin	null	null	https://www.cdc.gov/niosh/npg/npgd0005.html	NIOSH REL C 1 ppm (4 mg/m3) [15-minute]	Acetone cyanohydrin	https://referencesource.org/workplace-exposure-limits/acetone-cyanohydrin/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	4	C 1	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "75058 \| S \| Acetonitrile \| 40 \| 70 \| \| 60 \| 105", "value": "60" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_mgm3", "source": "https://www.dir.ca.go...	75-05-8	[]	acetonitrile	70	40	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetonitrile \| 75-05-8 \| 40 \| 70 \| - \|	Acetonitrile	https://referencesource.org/workplace-exposure-limits/acetonitrile/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
null	98862	null	acetophenone	49	10	https://www.dir.ca.gov/title8/5155.html	98862 \| \| Acetophenone \| 10 \| 49	Acetophenone	https://referencesource.org/workplace-exposure-limits/acetophenone/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0008.html", "source_quote": "NIOSH REL C 2500 ppm (2662 mg/m3)", "value": "C 2500" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg...	74862	[]	acetylene	null	null	https://www.dir.ca.gov/title8/5155.html	74862 \| \| Acetylene \| (h)	Acetylene	https://referencesource.org/workplace-exposure-limits/acetylene/	[ "cas_number", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_statement", "source": "https://www.cdc.gov/niosh/npg/npgd0009.html", "source_quote": "NIOSH REL See Appendix D", "value": "See Appendix D" } ]	79-27-6	[]	acetylene-tetrabromide	14	1	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acetylene tetrabromide \| 79-27-6 \| 1 \| 14 \| - \|	Acetylene tetrabromide	https://referencesource.org/workplace-exposure-limits/acetylene-tetrabromide/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "50782 \| \| Acetylsalicylic acid (Aspirin) \| -- \| 5", "value": "5" } ]	50-78-2	[]	acetylsalicylic-acid	null	null	https://www.cdc.gov/niosh/npg/npgd0010.html	NIOSH REL TWA 5 mg/m3	Acetylsalicylic acid	https://referencesource.org/workplace-exposure-limits/acetylsalicylic-acid/	[ "cas_number", "rel_mgm3", "substance" ]	null	TWA 5	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "ceiling", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "107028 \| S \| Acrolein \| 0.1 \| 0.25 \| C", "value": "C" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd...	107-02-8	[]	acrolein	0.25	0.1	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acrolein \| 107-02-8 \| 0.1 \| 0.25 \| - \|	Acrolein	https://referencesource.org/workplace-exposure-limits/acrolein/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0012.html", "source_quote": "NIOSH REL Ca TWA 0.03 mg/m3 [skin]", "value": "TWA 0.03" } ]	79-06-1	[ { "field": "pel_mgm3", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Acrylamide \| 79-06-1 \| - \| 0.3 \| X \|", "value": "0.3" }, { "as_of": "...	acrylamide	0.3	null	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Acrylamide \| 79-06-1 \| - \| 0.3 \| X \|	Acrylamide	https://referencesource.org/workplace-exposure-limits/acrylamide/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0013.html", "source_quote": "NIOSH REL TWA 2 ppm (6 mg/m3) [skin]", "value": "TWA 2" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/n...	79107	[]	acrylic-acid	5.9	2	https://www.dir.ca.gov/title8/5155.html	79107 \| S \| Acrylic acid \| 2 \| 5.9	Acrylic acid	https://referencesource.org/workplace-exposure-limits/acrylic-acid/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "107131 \| S \| Acrylonitrile; see Section 5213 \| 2 \| 4.5", "value": "2" }, { "as_of": "2026-08-05T00:00:00", "field": "pel_mgm3", "source": "https://www.dir.c...	107-13-1	[]	acrylonitrile	null	null	https://www.cdc.gov/niosh/npg/npgd0014.html	NIOSH REL Ca TWA 1 ppm C 10 ppm [15-minute] [skin]	Acrylonitrile	https://referencesource.org/workplace-exposure-limits/acrylonitrile/	[ "cas_number", "rel_ppm", "substance" ]	null	null	TWA 1	null	null	null
null	124049	null	adipic-acid	5	null	https://www.dir.ca.gov/title8/5155.html	124049 \| \| Adipic acid \| -- \| 5	Adipic acid	https://referencesource.org/workplace-exposure-limits/adipic-acid/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_ppm", "source": "https://www.cdc.gov/niosh/npg/npgd0015.html", "source_quote": "NIOSH REL TWA 4 ppm (18 mg/m3)", "value": "TWA 4" }, { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npg...	111693	[]	adiponitrile	8.8	2	https://www.dir.ca.gov/title8/5155.html	111693 \| S \| Adiponitrile \| 2 \| 8.8	Adiponitrile	https://referencesource.org/workplace-exposure-limits/adiponitrile/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-09-08T00:00:00", "field": "rel_mgm3", "source": "https://www.cdc.gov/niosh/npg/npgd0016.html", "source_quote": "NIOSH REL Ca TWA 0.25 mg/m3 [skin]", "value": "TWA 0.25" } ]	309-00-2	[]	aldrin	0.25	null	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Aldrin \| 309-00-2 \| - \| 0.25 \| X \|	Aldrin	https://referencesource.org/workplace-exposure-limits/aldrin/	[ "cas_number", "pel_mgm3", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "107186 \| S \| Allyl alcohol \| 0.5 \| 1.25 \| \| 4 \| 10", "value": "4" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_mgm3", "source": "https://www.dir.ca....	107-18-6	[ { "field": "pel_ppm", "versions": [ { "as_of": "2026-08-05T00:00:00", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Allyl alcohol \| 107-18-6 \| 2 \| 5 \| X \|", "value": "2" }, { "as_of": "2...	allyl-alcohol	5	2	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Allyl alcohol \| 107-18-6 \| 2 \| 5 \| X \|	Allyl alcohol	https://referencesource.org/workplace-exposure-limits/allyl-alcohol/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "107051 \| \| Allyl chloride \| 1 \| 3 \| \| 2 \| 6", "value": "2" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_mgm3", "source": "https://www.dir.ca.gov/tit...	107-05-1	[]	allyl-chloride	3	1	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Allyl chloride \| 107-05-1 \| 1 \| 3 \| - \|	Allyl chloride	https://referencesource.org/workplace-exposure-limits/allyl-chloride/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "pel_ppm", "source": "https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1", "source_quote": "Allyl glycidyl ether (AGE) \| 106-92-3 \| (C)10 \| (C)45 \| - \|", "value": "(C)10" }, { "as_of": "2026-08-05T00:00:00", "fie...	106-92-3	[]	allyl-glycidyl-ether	null	null	https://www.cdc.gov/niosh/npg/npgd0019.html	NIOSH REL TWA 5 ppm (22 mg/m3) ST 10 ppm (44 mg/m3) [skin]	Allyl glycidyl ether	https://referencesource.org/workplace-exposure-limits/allyl-glycidyl-ether/	[ "cas_number", "rel_mgm3", "rel_ppm", "substance" ]	null	22	TWA 5	null	null	null
[ { "as_of": "2026-08-05T00:00:00", "field": "stel_ppm", "source": "https://www.dir.ca.gov/title8/5155.html", "source_quote": "2179591 \| \| Allyl propyl disulfide \| 2 \| 12 \| \| 3 \| 18", "value": "3" }, { "as_of": "2026-08-05T00:00:00", "field": "stel_mgm3", "source": "https://www.dir...	2179-59-1	[]	allyl-propyl-disulfide	12	2	https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1000TableZ1	Allyl propyl disulfide \| 2179-59-1 \| 2 \| 12 \| - \|	Allyl propyl disulfide	https://referencesource.org/workplace-exposure-limits/allyl-propyl-disulfide/	[ "cas_number", "pel_mgm3", "pel_ppm", "substance" ]	null	null	null	null	null	null

End of preview. Expand in Data Studio

US workplace chemical exposure limits: federal OSHA, Cal/OSHA and NIOSH, side by side

Canonical, always-current version: https://referencesource.org/workplace-exposure-limits/ Machine-readable: https://referencesource.org/workplace-exposure-limits/data.json — this mirror is a point-in-time copy.

Last verified: 2026-09-25
Stale after: 2027-09-25 (past this date, prefer the canonical copy — it re-verifies on a cadence this snapshot does not)
Records: 812

Airborne exposure limits for workplace chemicals as stated by three independent authorities: federal OSHA's Table Z-1 (29 CFR 1910.1000), California's own Table AC-1 (8 CCR 5155), and NIOSH's Pocket Guide entry for the substance. Each record is one substance with the limit that agency publishes for it, the URL it came from and the verbatim line it was read from. The product is the disagreement: where more than one of them covers a substance the numbers are frequently far apart — acetone is 1000 ppm federally, 500 ppm in California and 250 ppm recommended by NIOSH; acetaldehyde is 200 ppm federally against 25 ppm in California; 1,1-dimethylhydrazine 0.5 against 0.01 — and exceeding a PEL is what triggers engineering controls, PPE and medical surveillance, so which number applies is consequential. OSHA's and California's are legal limits (PELs); NIOSH's is a recommendation (an REL), which is why it is carried in its own fields and never mixed into the PEL columns. Answers 'what is the exposure limit for [chemical]?', 'is the California PEL different from OSHA's?', 'what is the NIOSH REL for acetone' — the questions where an assistant gives one number without saying whose it is, or hands back an REL when it was asked for the legal limit.

Provenance — what every record carries

Every record carries source (the URL the value was read from) and source_quote (a verbatim quote from that page stating it). A value you cannot check against its page is indistinguishable from an invented one; these can all be checked. Each record is also individually addressable on the canonical site at its url.

Licence position

US federal and California government works — public domain. ACGIH TLVs deliberately excluded (copyrighted).

Facts are not copyrightable; what this dataset takes from each source is a fact plus a short attributed quote linking back to the page that states it.

Sources

Fields

See any record in data/records.jsonl — field names are self-describing, and the canonical page for each record renders them with labels: https://referencesource.org/workplace-exposure-limits/

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