Transcript Occupational Exposure to 1,3-Butadiene

Occupational Exposure
to 1,3-Butadiene
29 CFR 1910.1051
Chemical Identification
Gaseous monomer: CH2=CH-CH=CH2
 Stored as liquid under pressure
 Stabilizer added to prevent formation of
polymer during storage
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Production and Use
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US production, 1991: 3 billion pounds (almost all by
ethylene co-product process)
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Used in manufacture of
» Rubber (about 60% of total)
» Precursors of Nylon
» Rocket propellants
» Lubricating oil additives
» Agricultural fungicides
» Latexes
» Resins
» Industrial solvents
» Anthroquinone dyes
Health Effects
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CNS effects (e.g., headaches, nausea, blurred
vision) from very high acute exposures
Eye, nose, and throat irritation
Irritation and frostbite from contact with liquefied
butadiene
Leukemia and other lymphohematopoietic
cancers and possible reproductive effects from
chronic exposures
Benefits of Standard
7600 US workers exposed to significant
concentrations of butadiene, as high as
10 ppm
 New standard estimated to prevent at
least 59 cancer deaths over a 45-year
working lifetime
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History of Butadiene (BD)
Rulemaking
1971 - OSHA adopted original standard
for BD: 1000 ppm (TWA) Source: 1968
ACGIH TLVs
 1983 - NTP determined BD causes
cancer in rodents; OSHA and EPA
published RFI
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History (cont’d)
1984 - EPA published ANPR under
TSCA; various unions petitioned OSHA
for ETS; petitions denied
 1985 - EPA completed risk assessment
and referred BD to OSHA
 1986 - OSHA published ANPR
 1990 - OSHA published PR with 2 ppm
TWA and 10 ppm STEL
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History (cont’d)
1992 - IARC designated BD as
probable human carcinogen
 1996 - Joint labor/industry group
submitted voluntary agreement outlining
recommendations for final rule; OSHA
requested comments on recommendations; final rule published November 4,
1996: PELs of 1 ppm TWA, 10 ppm
STEL, and AL of 0.5 ppm
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Unique Features of Standard
Respirators - Short replacement
intervals specified for air-purifying
cartridges/canisters because of rapid
breakthrough and migration of BD
through filter elements
 Medical Surveillance - Periodic review of
aggregated information from medical
screening program to determine whether
employees adversely affected by BD
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Unique Features (cont’d)
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Written Exposure Goal Program
» Required where exposures > AL
» Includes the following unless employer can show
they are not feasible, effective, or necessary:
– Leak detection and prevention
– Local exhaust ventilation maintenance
– Pump exposure control technology
– Gauging devices to limit exposure
– Unloading devices to limit exposure
– Engineering controls in control rooms
(a) Scope and Application
All occupational exposures to 1,3Butadiene (BD)
 Exceptions
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» Objective data
» Liquid mixtures containing 0.1% or less BD
by volume
» BD or liquid mixtures in intact containers or
sealed transportation pipelines
(b) Definitions
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“Business day” - any Monday through Friday,
except those days designated as federal, state,
local or company specific holidays
“Complete Blood Count (CBC)”
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White blood cell count (WBC)
Hematocrit (Hct)
Hemoglobin (Hgb)
Differential count of white blood cells
Red blood cell morphology
Red blood cell indices
Platelet count
(b) Definitions (cont’d)
“Day” - any part of a calendar day
 “Emergency situation” - any occurrence
such as, but not limited to, equipment
failure, rupture of containers, or failure of
control equipment that may or does
result in an uncontrolled significant
release of BD
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(c) Permissible Exposure Limits
(PELs)
8-Hour TWA: 1 ppm
 STEL: 5 ppm
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There is also an Action Level (AL) of 0.5 ppm
established by the standard.
(d) Exposure Monitoring
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Representative; breathing zone samples
Initial monitoring unless
» Objective data exist
» Equivalent monitoring within previous two
years
Periodic monitoring
» Where results at or above AL but at or below
both PELs
» Where either PEL exceeded
(d) Exposure Monitoring (cont’d)
Termination of monitoring
 Additional monitoring
 Accuracy of monitoring
 Employee notification of results
 Observation of monitoring
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(e) Regulated Areas
Wherever exposures exceed or can be
expected to exceed either PEL
 Limited access
 Demarcation of area
 Communication with other employers
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(f) Methods of Compliance
Engineering controls and work practices
 Respirators as supplemental protection
 Written compliance plan
 Employee rotation as a method of
compliance prohibited
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(g) Exposure Goal Program
Written plan
 Required where exposure exceeds AL
 Updated as necessary
 Respirator use not required
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(g) Exposure Goal Program (cont’d)
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Includes the following (unless not feasible,
not effective, or not necessary to reduce
exposures below AL)
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Leak detection and prevention program
Local exhaust ventilation maintenance
Pump exposure control technology
Gauging devices to limit exposure
Unloading devices to limit exposure
Engineering controls in control rooms
(h) Respiratory Protection
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Allowable during time to implement engineering and work
practice controls and as supplement where such are not
adequate to achieve PELs; for non-routine, infrequent, and
limited-duration operations; in emergencies
Respirator program in accordance with 29 CFR 1910.134
(b) - (d) [except (d)(1)(iii), (d)(3)(iii)(B)(1), and (2)] and (f) (m)
Selection governed by Table 1; NIOSH-approved under 42
CFR Part 84
PAPRs or supplied air respirators provided for employees
who cannot use negative pressure respirators
(h) Respiratory Protection (cont’d)
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Replacement intervals for cartridges/
canisters governed by
» Table 1 or
» 90% of expiration-of-service life or
» NIOSH-approved end-of-service-life
indicator (when available)
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Replacement mandatory any time an
employee can smell BD
(i) Protective Clothing and
Equipment
To prevent eye contact and limit dermal
exposure
 Eye and face protection governed by 29
CFR 1910.133
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(j) Emergency Situations
Written plan for applicable elements of
29 CFR 1910.38, “Employee Emergency
Plans and Fire Prevention Plans”
 29 CFR 1910.120, “Hazardous Waste
Operations and Emergency Response”
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(k) Medical Screening and
Surveillance
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Coverage
» Currently exposed employees
» Previously exposed employees
Administration by physician or other licensed health care
professional
Frequency
» Health questionnaire and complete blood count annually
» Physical examinations initially, every 3 years or more
frequently at discretion of licensed health care
professional, and at termination if 12 or more months have
elapsed
» Within 48 hours following an emergency
(k) Medical Screening and
Surveillance (cont’d)
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Content
» For anticipated exposure
» For emergency exposure
Written medical opinion to employer and
employee within 15 business days
Periodic review of aggregated medical screening
data to determine whether employee population
adversely affected by exposure; employees
informed of any information learned
(l) Communication of BD Hazards to
Employees
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Communication of hazards as required by Hazard
Communication Standard
Training program for employees potentially
exposed at or above the AL or STEL to be
repeated annually
Contents of training program beyond the Hazard
Communication Standard
» Medical screening and surveillance
» Contents of standard and appendices
» Rights to employee medical and exposure records
(m) Recordkeeping
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Objective data for exemption from initial
monitoring - maintain for duration of reliance on
data
Exposure measurements - maintain for 30 years
Respirator fit test records - maintain until next fit
test
Medical screening and surveillance - maintain for
duration of employment plus 30 years
(n) Dates
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Effective date: February 2, 1997
Start-up dates:
» Initial monitoring within 60 days of effective date
» Engineering controls within 2 years of effective
date
» Exposure goal program within 3 years of effective
date
» Other requirements, including feasible work
practice controls, within 180 days of effective date
(o) Appendices
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Informational
» A - Substance Safety Data Sheet for 1,3-Butadiene
» B - Substance Technical Guidelines for 1,3Butadiene
» C - Medical Screening and Surveillance for 1,3Butadiene
» D - Sampling and Analytical Method for 1,3Butadiene
» F - Medical Questionnaires
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Reserved - Appendix E