Environmental Protection Agency in the U.S. released a health-impact
report on diesel exhaust. Although the long-term health effects
of diesel exhaust are uncertain, studies strongly suggest a cancer
risk to humans.
provides practical advice on how to reduce exposure to diesel emissions
be exposed to diesel exhaust almost anywhere as they operate or
work around equipment such as
elevating work platforms
as diesel fumes, diesel exhaust is a complex mixture of gases and
diesel particulate matter (DPM). Components include
- carbon monoxide
- carbon dioxide
including benzene and formaldehyde
aromatic hydrocarbons (PAHs)
- soot (carbon).
The major component
of diesel exhaust is soot (60%-80%). This is what you see coming
out of the exhaust pipe.
Most of the
DPM, also known as fine particulate matter, consists of particles
so tiny they are easily inhaled and deposited in the lower lungs
where they cause various health effects.
In the short
term, breathing in diesel fumes can cause coughing, itchy or burning
eyes, chest constriction, wheezing, and difficulty breathing. These
effects disappear when the worker is away from the source of the
Over the long
term (20 years or so), exposure to diesel fumes may increase the
risk of lung cancer and possibly bladder cancer. There is additional
evidence that the fine particles in DPM can aggravate heart problems
and respiratory illnesses such as asthma.
How can exposure be controlled?
construction site is unique, some common actions can be taken to
reduce exposure to diesel exhaust.
Use low-sulphur diesel fuel (less than 0.05% sulphur). This reduces
emissions and assciated odours
- engine wear
Retrofit engines with an exhaust filtration device to capture DPM
before it enters the workplace. The most common exhaust filtration
diesel exhaust paper filters
- diesel particulate
Locate the exhaust pipe so that diesel fumes are directed away from
the operator and nearby workers. This simple measure can make a
big difference in the fume concentration to which personnel are
Use a catalytic converter to reduce carbon monoxide, aldehydes,
and hydrocarbons in diesel fumes. These devices must be used with
low sulphur fuels. Using converters with high-sulphur diesel fuels
may do more harm than good to air quality.
Ventilate wherever diesel equipment operates indoors. Roof vents,
open doors and windows, roof fans, or other mechanical systems can
be used to move fresh air through work areas. As buildings under
construction are gradually enclosed, remember that fumes from diesel
equipment operating indoors can build up to dangerous levels without
Attach a hose to the tailpipe of a diesel vehicle running indoors
and exhaust the fumes outside where they can’t reenter the
workplace. Because exhaust hoses tend to be treated roughly, inspect
them regularly for defects and damage.
Use enclosed, climate-controlled cabs pressurized and equipped with
high efficiency particulate air (HEPA) filters to reduce operators’
exposure to diesel fumes. Pressurization ensures that air moves
from inside to outside. HEPA filters ensure that any air coming
in is filtered first.
Regular maintenance of diesel engines is essential to keep exhaust
emissions down. Follow the manufacturer’s recommended maintenance
schedule and procedures. Smoke colour can signal the need for maintenance.
For example, blue/black smoke indicates that an engine requires
servicing or tuning.
Work practices and training can help reduce exposure. Here are just
- Turn off
engines when vehicles are stopped for more than a few minutes.
Idling wastes fuel and increases diesel emissions.
- Train diesel-equipment
operators to perform routine inspection and maintenance. For instance,
operators should know when to change exhaust filtration devices.
When purchasing a new vehicle, ensure that it’s equipped with
the most advanced emission control systems available.
With older vehicles, use electric starting aids such as block heaters
to warm the engine, avoid difficulty starting, and thereby reduce
Respirators are only an interim measure to control exposure to diesel
emissions. In most cases an N95 respirator is adequate. Note the
following points about respirator use.
are for interim use only, until primary controls such as ventilation
can be implemented.
must be trained and fit-tested before they wear respirators. A
competent person familiar with the selection, care, and use of
respirators must perform the fit testing.
must bear a National Institute of Occupational Safety and Health
(NIOSH) approval number. Never use paper masks or surgical masks
without NIOSH approval numbers.
must be clean-shaven when wearing respirators. Beards, even stubble,
will allow some fumes to bypass the respirator and be inhaled.
respirators to make an effective seal, wearers must be clean-shaven.