19085-1701857-UL_Prop_65_Test_Results_2019

Released by UL Environment
Date Prepared:
February 11, 2019
Report #:
1000339735-1162663EA
©2019 UL LLC
CA Prop 65 Exposure Assessment Page 9 | 15
Following OEHHA guidance, the office and school classroom scenarios estimate that an
exposed consumer inhales indoor air during a typical eight-hour work day and that the volume
of inhaled air is 10 m
3
(OEHHA, 2009, Table 2). Within the residential scenario, it is assumed
that indoor air is mixed throughout the house and exposure is not limited to an 8-hour work day.
Daily exposure within the residential office scenario is therefore based on a 24-hour inhalation
volume of 20 m
3
(OEHHA, 2000). The American Industrial Hygiene Council’s Exposure Factors
Sourcebook (AIHC, 1994) recommends age-specific breathing rates, as well as a distribution of
breathing rates based on the information developed by the U.S. EPA (2011). Specifically, the
AIHC recommends point-estimate default daily breathing rates of 18.9 m
3
/day for individuals six
to 70-years old and 17.3 m
3
/day for children under six. The AIHC also recommends a point-
estimate default value of 12 m
3
/day for children one to four years old by adjusting the ventilation
rate for six-year-old children by 0.75 (OEHHA, 2000). Therefore, the use of a 20 m
3
inhalation
volume conservatively overestimates a child’s daily exposure. The expected frequency of
exposure within the private office and school classroom scenarios is estimated as 250 work
days per year (OEHHA, 2005). The employment duration is estimated to be 25 years as this
value has been suggested as a reasonable estimate of the 95
th
percentile within the OEHAA
Hot Spots program (OEHHA, 2012). The home residence scenario assumes an exposure
frequency of 350 days per year and an exposure duration of 30 years following OEHHA
guidance (OEHHA, 2012).
Table 2. Exposure parameters used in the LADD calculations for each exposure scenario
Parameter
Private
Office
School
Classroom
Home
Residence
Reference
Breathing Rate
(m
3
/day)
10 10 20 OEHHA, 2000
Exposure
Frequency
(days/year)
250 250 350 OEHHA, 2005
Exposure Duration
(years)
25 25 30 OEHHA, 2012
The consumer’s LADD values (Table 3) are conservatively calculated for the private office,
school classroom, and home residence scenarios using the exposure parameters summarized
in Table 2, the product specific emission rates as reported in UL Test Report # 1000333735-
1162663, and the upper bound surface area of the Execumat Chair Mats. The modeled
exposures summarized in Table 3 indicate that the Execumat Chair Mats, within all three
exposure scenarios, will result in consumer LADDs that are less than the 1,4 dioxane,
acetaldehyde and cumene NSRLs of 30 µg/day, 90 µg/day and 3.7 µg/day respectively.