Documentation for Immediately Dangerous to Life or Health Concentrations (IDLHs)

(for IDLH documentation)

A1       confirmed human carcinogen (ACGIH)
A2       suspected human carcinogen (ACGIH)
A3       animal carcinogen (ACGIH)
A4       not classifiable as a human carcinogen (ACGIH)
A5       not suspected as a human carcinogen (ACGIH)
ACGIH    American Conference of Governmental Industrial Hygienists
AIHA     American Industrial Hygiene Association
CAS      Chemical Abstract Service
CF       correction factor for LC data
CFR      Code of Federal Regulations
EEGL     emergency exposure guidance level (NRC)
ERPG     emergency response planning guideline (AIHA)
IDLH     immediately dangerous to life or health concentration value 
i.p.     intraperitoneal
i.v.     intravenous
kg       kilogram
LC       lethal concentration
LC50     concentration causing death in 50%
LCLo     lowest concentration causing death
LD       lethal dose
LD50     dosage causing death in 50%
LDLo     lowest dosage causing death
LEL      lower explosive limit
mg/kg    milligrams per kilogram of body weight
mg/m3    milligrams per cubic meter of air
mmHg     millimeters of mercury (pressure measurement)
mppcf    millions of particles per cubic foot of air
NIOSH    National Institute for Occupational Safety and Health
NRC      National Research Council
OSHA     Occupational Safety and Health Administration
PEL      permissible exposure limit (OSHA)
ppm      parts per million parts of air
RD50     concentration producing a 50% decrease in respiratory
         rate following a 10-minute exposure
REL      recommended exposure limit (NIOSH)
s.c.     subcutaneous
SCP      Standards Completion Program (NIOSH/OSHA)
SPEGL    short-term public emergency guidance level (NRC)
STEL     Short-term exposure limit
TCLo     lowest concentration resulting in a toxic effect  
TDLo     lowest dose resulting in a toxic effect
TLV      threshold limit value (ACGIH)
TWA      time-weighted average

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