Download Advice for working with sewage-contaminated silt and soil

FAC T
S H E E T
ADVICE FOR WORKING WITH SEWAGECONTAMINATED SILT AND SOIL
In natural disaster situations, widespread
Moulds and fungi
deposits of liquefacted silt may spread over
Moulds, fungi and some bacteria favour musty
a wide area.
and wet conditions, and can be found where
It is quite likely that soil, silt or liquefied material
water has leaked into buildings from:
could be contaminated with sewage and/or
>> damaged roofs, windows, roof tiles
stormwater, if underground services rupture.
It will not be easy to determine if such
contamination has occurred.
Any silt in affected residential areas should
be considered as potentially contaminated.
Silt may still remain under or around dwellings
and other buildings.
HEALTH RISKS
Bacteria, viruses and parasites
There is the potential for ill health from
bacteria, viruses and parasites from sewage.
It is thought that these can live in wet silt or
wet environments for many months. The main
and gutters
>> places where wet silt has been in contact
with house structures such as wooden
floors or piles
>> places where dampness has entered
wall cavities.
Moulds and fungi produce tiny particles called
spores. These can easily become airborne and
be inhaled, especially when mouldy material
is disturbed (for example, when pulling gib
from walls or digging around wooden piles),
or in dusty, windy environments. Some moulds
produce toxins that can be a danger to health.
health risks when working with contaminated
Moulds and fungi can cause a hacking cough,
silt are gastro-intestinal illnesses, including
respiratory problems (eg shortness of breath
E.Coli, Salmonella and Campylobacter.
or wheezing), nose or throat irritation, nasal
Other potential health hazards include skin
and sinus congestion, eye irritation, allergic
infections, leptospirosis and viral illnesses
reactions, skin rashes/irritation and worsen
such as hepatitis.
pre-existing asthma.
Workers will be most at risk of coming into
HOW TO MINIMISE CONTACT WITH
contact with bacteria through oral ingestion
or from direct contact with skin (eg facial
splashes). Broken skin is also another avenue
>> Minimise time spent in damp attics, cellars,
sheds or inside and under buildings where
silt, moulds or fungi may be present.
WSNZ_1800_Jan 16
for bacterial infection.
BACTERIA, VIRUSES, MOULDS AND FUNGI
worksafe.govt.nz
0800 030 040
>> Always avoid direct contact with silt,
Contaminated silt disposal
especially if it is wet, and avoid areas
Contact the local authority (council) in
contaminated with mould or fungi.
advance about where, and how, to dispose
>> Do not splash in pools of water, even
if it looks clean.
>> Use appropriate personal protective
equipment (PPE), including full-covering
disposable overalls, waterproof gloves,
gumboots and a respirator. A P2 or P3
particulate disposable face mask suitable
for biological aerosols should be used.
>> Never eat, drink, smoke or bite your nails
while carrying out any work where it is
of contaminated silt.
Further advice
WorkSafe New Zealand: phone 0800 030 040
Resources
Confined spaces: Planning entry and working
safely in a confined space available from
www.worksafe.govt.nz
PUBLISHED: January 2016. CURRENT UNTIL REVIEW IN 2018
likely that contact with silt, moulds or
fungi will occur.
>> During work breaks, remove PPE, wash
hands and/or use hand sanitiser before
eating, drinking or smoking.
>> When working inside buildings, ensure
adequate ventilation by opening windows
and doors.
>> Consider using a fresh air blower and
trunking (ducts/hoses connected to the
blower) if working in poorly ventilated
spaces both inside and outside, or
under, buildings.
>> After work is completed, always take a
shower, place dirty overalls carefully in a
separate bag to avoid cross-contamination
and if re-usable, wash them separately from
other clothes in hot water and detergent.
>> If a worker comes into contact with silt,
moulds or fungi and feels unwell, that
person should seek medical advice and
tell the General Practitioner (GP) about
where they were working and what they
were doing.
worksafe.govt.nz
0800 030 040