1. Construction Safety Talks
SILENT KILLER - Some things to know before you give your talk
One hundred people die in confined spaces each year. It is not always
THE CONFINED evident that the space you are about to enter is a killer! Without a policy for
SPACE evaluating these spaces, employees may inadvertently enter a confined
space not suitable for human occupancy. Most confined space fatalities are
No. 84 caused by gases that you can not see, taste, or smell.
What does a Confined Space look like?
How This Talk • They have limited access
Applies To My • They contain or can accumulate toxic contaminants
Crew: • They can become oxygen deficient
• They are not designed for normal human occupancy
Ask the crew
Can you give me an example of a toxic contaminant? Carbon monoxide,
carbon dioxide, and hydrogen sulfide are three common contaminants. All
three gases displace oxygen and cause health problems. How about
flammable gases such as methane? Methane is a by-product of
decomposing organic materials. Flammable gases can also come from
leaking underground tanks by traveling miles underground and seeping
through a small crack or joint into a below-ground space.
Oxygen deficiency occurs when the amount of oxygen in the air falls to less
than 19.5% of the volume. Normally oxygen makes up 20.9% of air at sea
level along with nitrogen (78.1%), carbon dioxide (0.03%), water vapor
(varies day to day), and rare gases such as argon, helium, krypton, neon,
radon, and xenon (0.97%).
Tips
• Know how to recognize a confined space. Ask for other examples.
Tanks, pits, pressure vessels, vaults, and trenches all qualify.
• Know the company’s confined space entry polices and who to
contact to get a space approved for entry.
• Know how to get help if a worker has problems while working in a
confined space. This should summon trained responders equipped
with self-contained breathing apparatus.
• If you suspect a hazard, immediately bring it to the attention of a
supervisor.
• Do Not enter Permit-Required confined spaces unless you are
authorized and trained to do so.
• Do Not enter a confined space, even to rescue someone. Instead,
institute the emergency plan. Historically, 60% of fatalities in
confined spaces are would-be rescuers!
© 2005 Liberty Mutual Group – All Rights Reserved 1

2. Remember, too, that all the other hazards you face on the job can also be present in a confined
space. Falls, electric shock, burns, and falling/flying objects may be exposures in the space and
from the work being performed.
Try this for show and tell!
Show the crew the instruments you use to test a confined space before entry. Tell
them what it tests for .
Attended by : _______________ ________________ _______________
_______________ ________________ _______________
_______________ ________________ _______________
_______________ ________________ _______________
_______________ ________________ _______________
The illustrations, instructions and principles contained in the material are general in scope and, to the best of our knowledge, current at
the time of publication. No attempt has been made to interpret any referenced codes, standards or regulations. Please refer to the
appropriate code, standard or regulation making authority for interpretation or clarification.
© 2005 Liberty Mutual Group – All Rights Reserved 2