LACS R7 Samples Will be
w/c 29th April
Deadline Date is
Low Asbestos Content Scheme (LACS) assesses the performance
of laboratories carrying out the identification and quantification
of asbestos at low concentrations. LACS is operated by HSL, which
oversees management, registration, and membership matters together
with distribution of the samples and processing the participant
Analytes in the Scheme
Amosite, chrysotile, crocidolite, tremolite, anthophyllite and
actinolite in various matrices such as solids and powders. The
scheme has the advantage that it includes both common and less
common forms of asbestos. The asbestos content will range
from 0.01 - 0.1%.
Who Should Participate?
Laboratories who wish to monitor and improve the quality of
their asbestos measurements. This scheme will enable
laboratories to demonstrate their competence with respects to
Operation of the Scheme
The LACS year operates from April to March and test materials
are distributed to participants quarterly with distribution dates
detailed in the LACS schedule. These are normally in-line with
distribution dates for AIMS.
The test materials used in the scheme are all manufactured in
the laboratory and do not necessarily reflect typical asbestos
containing materials used in buildings. Also, whilst the six
regulated asbestos types will be included, it is not
anticipated that all six will be used every year and laboratories
should not rely on LACS to demonstrate analytical competence in the
identification of the six regulated asbestos types. From time
to time more unusual samples and naturally occurring industrial
minerals will be included.
Test materials may contain up to three different asbestos types
or no asbestos at all. A range of non-asbestos fibres may
also be included. Each sample is individually manufactured by
careful weighing and mixing of the asbestos component(s) and matrix
A representative sub-set of all test materials is fully
validated against detailed criteria before introduction into LACS.
The validation laboratories are normally accredited to ISO 17025
for the measurement of asbestos in bulk materials.
There is no recommended method for LACS although the low
asbestos content suggests many laboratories will use electron
microscopy techniques. However, in order to ensure detection of all
asbestos types present, it is strongly recommended that the sample
is analysed in its entirety.
Participants obtain a round score for the qualitative assessment
(identification of asbestos types present) and a Z-score for the
The Proficiency Testing Team
Health and Safety Laboratory
Tel: +44 (0) 203 028 3382