Proposed Amendments to the Workplace
Exposure Standards for Airborne Contaminants
for Synthetic Mineral Fibres – Mineral Wools
Issues Paper
April 2012
Table of Contents
Foreword .................................................................................................................................... 3
Purpose...................................................................................................................................... 3
Objective .................................................................................................................................... 3
Rationale for existing exposure standard .................................................................................... 4
Industry develops lower biopersistent fibres ............................................................................... 4
New evidence – Evaluation by IARC .......................................................................................... 4
Review of the WES for mineral wools ......................................................................................... 5
AIOH Advice............................................................................................................................... 5
Proposed changes to the WES................................................................................................... 3
Invitation to comment on the proposed amendments to the WES............................................... 6
How to make a submission ............................................................................................................. 6
What happens after the public comment period closes? ................................................................ 7
Appendix A – Amendment to the WES ....................................................................................... 8
Foreword
Safe Work Australia is the national organisation with primary responsibility to improve work
health and safety and workers’ compensation arrangements across Australia. Safe Work
Australia consists of representatives of the Commonwealth, state and territory governments,
the Australian Council of Trade Unions, the Australian Chamber of Commerce and Industry
and the Australian Industry Group.
One of Safe Work Australia’s key functions is the development and maintenance of a model
Work Health and Safety (WHS) Act, supported by model WHS Regulations, model Codes of
Practice and a national compliance and enforcement policy for adoption across Australia.
Under the Inter-governmental Agreement for Regulatory and Operation Reform in
Occupational Health and Safety, the Commonwealth, state and territory governments have
committed to adopting and implementing the model WHS legislation and model Codes of
Practice as agreed by the Workplace Relations Ministers’ Council.
Purpose
The purpose of this consultation paper is to seek comment on a proposed amendment to the
Workplace Exposure Standard (WES) applicable to mineral wools, including rock, glass and
slag wools identified as mineral wools not otherwise specified (NOS). It is not proposed to
make changes to the WES for Refractory Ceramic Fibres (RCF).
Mineral wools, special purpose glass fibres, and RCF are uniquely referred to in Australia
collectively as Synthetic Mineral Fibres (SMF). Internationally, SMF are known more widely as
man-made vitreous fibres (MMVF) and are now listed on the Hazardous Substance Information
System (HSIS) with their synonyms.
The model WHS Regulations prescribe specific duties in relation to exposure standards.
Regulation 49 requires a person conducting a business or undertaking to ensure that no
person at the workplace is exposed to a substance or mixture in an airborne concentration that
exceeds the exposure standard for the substance or mixture.
Regulation 50 requires a person conducting a business or undertaking at a workplace to
ensure that atmospheric monitoring is carried out to determine the airborne concentration of a
substance or mixture at the workplace to which an exposure standard applies if:
the person is not certain on reasonable grounds whether or not the airborne
concentration of the substance or mixture at the workplace exceeds the relevant
exposure standard, or monitoring is necessary to determine whether there is a risk to
health.
The exposure standards referenced in the WHS Regulations are those published in the
Workplace Exposure Standards for Airborne Contaminants. This document, including
Guidance on the interpretation of workplace exposure standards for airborne contaminants is
available on www.safeworkaustralia.gov.au.
Objective
The objective of updating the WES for mineral wools is to ensure that it is consistent with the
current toxicological and epidemiological knowledge of the health effects of mineral wools, and
takes into account the development of less biopersistent fibres by industry. Despite the
widespread commercial development and use of low bio-persistent forms of SMFs for over 15
years, no specific WES for low biopersistent fibres has been developed.
Rationale for existing exposure standard
In 1989, the National Occupational Health and Safety Commission [NOHSC], Technical Report
on Synthetic Mineral Fibres, recommended on the basis of the limited available evidence, and
as a precautionary approach, that a WES for all forms of SMF be set at 1.0 fibres /ml with a
secondary yet complementary standard of 2 mg/m3 (inhalable dust). As a result, this respirable
fibre in air exposure standard was set by the tripartite Standards Development Committee and
adopted in the National Standard for Synthetic Mineral Fibres [NOHSC:10074 (1990)] as 0.5
fibres /ml with a complementary value of 2 mg/m3 (inhalable dust). This exposure standard was
applied to all forms of SMF - for mineral wools including, rock, glass and slag wools, as well as
special purpose glass fibres and RCF.
Assessment of airborne fibre levels is performed using the Membrane Filter Method for the
Estimation of Airborne Synthetic Mineral Fibres- a fibre counting method, analogous to the
method that is used for asbestos in air monitoring. Fibre counting analytical methods are time
consuming, require a level of expertise and are relatively expensive compared to gravimetric
methods in common use for less hazardous dusts and airborne particulates.
Industry develops lower biopersistent fibres
In order to address international concerns that such fibres could be as hazardous as asbestos,
manufacturers of mineral wools and RCF moved to develop lower biopersistent materials
during the 1980s. Low biopersistent fibres have been in commercial use since the early 1990s
and are now the type manufactured in Australia. Although lower quality imported products, as
well as old installed materials, are likely to have the old biopersistent formulations, the new
lower biopersisent materials have been found to be broken down or otherwise more rapidly
cleared from the lungs.
Toxicological test methods, such as the short term biopersistence test by inhalation, are used
to establish whether the formulation has low biopersistence. The European Commission (EC)
has recognised these new low biopersistent fibres as not presenting a carcinogenicity hazard,
and exonerates these materials from classification as carcinogens. This EC classification is
contained in the entry for mineral wools on the Hazardous Substances Information System
(HSIS). ‘Note Q’ on HSIS describes the biopersistence tests required. An explanation of Note
Q can be found at Appendix A to this paper.
New evidence – Evaluation by IARC
In 2002, the International Agency for Research on Cancer (IARC) undertook an evaluation of
new and more complete epidemiological studies and animal experimentation available pre and
post the original NOHSC review in 1989. In their overall evaluation IARC stated that; glass
wool, continuous glass filament, rock (stone) wool and slag wool (ie. mineral wools not
otherwise specified) were ‘not classifiable as to their carcinogenicity to humans’ (this was a
downgrade from IARC Group 2 (GHS Group 1B) to Group 3 (GHS Group 2)). See Attachment
B. The EC has not yet considered the IARC evaluation report and therefore has not yet
amended the classification of biopersistent mineral wools. The classification of mineral wools
as recorded on HSIS, which mirrors the European Substance Information System (ESIS), has
not yet been updated.
In the detail of IARC’s review, IARC stated that there is inadequate evidence in humans for the
carcinogenicity of the above mentioned mineral wools, limited evidence in animals for the
carcinogenicity of insulation glass wool, rock/slag wools; and inadequate evidence for
carcinogenicity in animals of continuous glass filament and new less biopersistent fibres,
including alkaline earth silicates.
For the new generation of low bio-persistent fibres, IARC elected not to make an overall
evaluation for the reasons of the non-effect evidence from animal studies and the lack of
epidemiological data at the time. As noted above, however, these new fibre types have been
exonerated by the European Commission from classification for carcinogenicity due to their low
biopersistence.
Review of the WES for mineral wools
The Insulation Council of Australia and New Zealand (ICANZ), the peak body for
manufacturers and importers of SMF, approached Safe Work Australia and requested that the
EC and IARC decisions be reflected in the regulatory controls imposed on synthetic mineral
fibres.
The ICANZ have published an Industry Code of Practice for the safe use of glass wool and
rock wool insulation products in consultation with unions (2002) and this Code was updated in
2003 to reflect the new IARC classification. It is currently the primary Code of Practice
promulgated by industry for users.
Safe Work Australia agreed to review the WES for mineral wools to take into account the IARC
assessment of the older biopersistent fibre types and the EC removal of the carcinogen
classification for new less biopersistent products.
AIOH Advice
In reviewing the WES, Safe Work Australia requested advice from the Australian Institute of
Occupational Hygienists (AIOH) as to what the exposure standard should be. The advice
provided by the AIOH (Attachment C) supports the assessment by IARC, and recommends
that for all mineral wools (biopersistent or not, except for RCF) the current WES of 0.5 fibres/ml
should be removed and the gravimetric exposure standard of 2 mg/m3 of inhalable dust be
applied. This recommended WES recognises the remaining hazard of these fibres, (i.e. their
upper respiratory tract irritation), as well as the installed product situation in Australian
workplaces, where glass wool products also have trapped general environmental dusts. The
AIOH recommended that this WES should be applied regardless of whether the mineral wool
meets ‘Note Q’ biopersistence test requirements, due to the upper respiratory tract irritation
hazard.
The AIOH, consistent with the IARC assessment, recommends that RCF and continue to have
the current WES of 0.5 respirable fibres/mL as well as a complementary WES of 2mg/m3
inhalable dust.
Proposed changes to the WES
The proposal is to amend the WES for mineral wools (not otherwise specified) to a gravimetric,
rather than fibre in air measure (2mg/m3 inhalable dust).
This will involve:
a.
b.
c.
d.
e.
For the Minerals Wools (not otherwise specified - e.g. glass wool, fibreglass and rock
wool), the WES be amended from 0.5 f/ml to a WES of 2 mg/m3 inhalable dust.
The WES for RCF remain at 0.5 fibres/ml, with a complementary WES of 2 mg/m3
inhalable dust.
The entries for RCF and mineral wools terminology in the ‘Workplace Exposure Standards
for Airborne Contaminants’ be made exactly the same as in HSIS (reflecting the European
ESIS) for international consistency.
HSIS and ‘Guidance on the Interpretation of Workplace Exposure Standards for Airborne
Contaminants’ to be amended to reflect the changes to WES.
The carcinogenicity category classifications for mineral wools of both the EC and IARC be
recorded for advice against the new WES entry for mineral wools.
The current and proposed listings for mineral wools can be found at Appendix A.
Invitation to comment on the proposed amendments to the WES
Interested persons are invited to make comment in connection with the proposed amendments
to the WES.
The public comment period will close at 5pm AEST Friday 8 June 2012.
How to make a submission
A Public Comment Submission Cover Sheet and the Public Comment Response Form are
provided for making written submissions. These are available on the Safe Work Australia
website at www.safeworkaustralia.gov.au.
Where comments are of a technical nature supporting evidence in the form of data or
references to data are sought.
It is preferred that submissions are typed and submitted electronically to the following email
address: chemicals@safeworkaustralia.gov.au. If you are unable to email your submission,
you can post it to:
Safe Work Australia
Attn: Proposed Amendments to the WES Public Comment
GPO Box 641
Canberra ACT 2601
When your submission is received by Safe Work Australia, you will be sent a receipt of
confirmation. All submissions will be made accessible to the public on the Safe Work Australia
website. Any information that you do not wish to be made available to the public should be
clearly marked ‘IN CONFIDENCE’.
What happens after the public comment period closes?
Safe Work Australia will analyse all written submissions that are received during the public
comment period and consider whether to revise the WES as outlined in this Issues paper.
Appendix A – Amendment to the WES
Current listings in the ‘Workplace Exposure Standards for Airborne Contaminants’
Synonyms
Cas No
TWA
(ppm)
TWA
(mg/m3)
STEL
(ppm)
STEL
(mg/m3)
Carcinogen
Category
Notices
Ref
-
-
-
0.5 f/ml##
0.5 f/ml
0.5 f/ml
0.5 f/ml
-
-
-
-
-
Synonyms
Cas No
TWA
(ppm)
TWA
(mg/m3)
STEL
(ppm)
STEL
(mg/m3)
Carcinogen
Category
Notices
Ref
Man-made Vitreous (Silicate) Fibres (MMVF) (Synthetic mineral fibres)
-
-
-
-
-
-
-
-
Refractory Ceramic Fibres, Special Purpose Fibres, with the exception of those specified elsewhere:
Manmade vitreous (silicate) fibres with random orientation with alkaline oxide and alkali earth oxide
(Na2O+K2O+CaO+ MgO+BaO) content less or equal to 18 % by weight)
-
-
-
0.5 f/ml;
2mg/m3
(inhalable
dust)
-
-
1B* /
Group 2B
(IARC)
H350i**
A,
R*
Mineral wool, with the exception of those specified elsewhere: Man-made vitreous (silicate) fibres with
random orientation with alkaline oxide and alkali earth oxide (Na2O+K2O+CaO+MgO+BaO) content
greater than 18 % by weight)
-
-
-
-
-
2* / Group
3 (IARC)
H351**
A, R,
Q*
Standard Name
Synthetic mineral fibres (SMF)
Ceramic Fibres
Glasswool (including superfine glassfibre)
Rockwool
Proposed listings in ‘Workplace Exposure Standards for Airborne Contaminants’
Standard Name
2 mg/m3
(inhalable
dust)
* Listed in the European Union's Annex I to Regulation (EC) No 1272/2008 (the Globally Harmonised System (GHS) as implemented within the EU) - applies from 1 December 2010, ** = see IARC
carcinogen category, ## includes a 2mg/m3 inhalable dust level for all synthetic mineral fibres (located within ‘Guidance on the Interpretation of Workplace Exposure Standards for Airborne
Contaminants’.
Category 1B = the assessment is based primarily on animal evidence, Category 2 = suspected human carcinogen, Group 2B = the agent (mixture) is possibly carcinogenic to humans. The
exposure circumstance entails exposures that are possibly carcinogenic to humans, Group 3 =the agent (mixture or exposure circumstance) is not classifiable as to its carcinogenicity to humans.
H350i = May cause cancer by inhalation, H351 = Suspected of causing cancer.
A = Without prejudice to Article 17(2), the name of the substance must appear on the label in the form of one of the designations given in Part 3. In Part 3, use is sometimes made of a general
description such as "... compounds" or "... salts". In this case, the supplier is required to state on the label the correct name, due account being taken of section 1.1.1.4.
R =The classification as a carcinogen need not apply to fibres with a length weighted geometric mean diameter less two standard geometric errors greater than 6 μm.
Q =The classification as a carcinogen need not apply if the substance fulfils one of the following conditions: - a short term biopersistence test by inhalation has shown that the fibres longer than 20 μm
have a weighted half-life less than 10 days; or - a short term biopersistence test by intratracheal instillation has shown that the fibres longer than 20 μm have a weighted half-life less than 40 days; or an appropriate intra-peritoneal test has shown no evidence of excess carcinogenicity; or - absence of relevant pathogenicity or neoplastic changes in a suitable long term inhalation test.