1. Gas Monitoring Basics
Presented by Dan Klimek
Sisk & Company

2. Objectives Purpose for air monitoring Your Air monitors (Gas Testers)
Overview of gas monitoring
Bump Testing
Using the meters
Reading Monitor
What to look for – JSA
Confined Space
Excavation & Trenching
Hot Work
What to do if there is a problem
Mitigation

3. Purpose for air monitoring
Why Monitor the air?
Air monitoring is used to determine the amount of various gases in the atmosphere.
Some times we want to confirm that there is enough of something – like oxygen.
Other times we want to make sure there is not too much of something -- like toxic or flammable gases / vapors.
You need to monitor the atmosphere to make sure gas / vapor levels at within “safe” ranges.

4. What are the gases you monitor?
Purpose for air monitoring
Tell me about the air
What are the gases you monitor?

5. Tell me about the air – Why these?
Purpose for air monitoring
Tell me about the air – Why these?
Oxygen
Flammable
Toxics

6. Air monitoring can be done by these devices and methods:
Your Air monitors
Air monitoring can be done by these devices and methods:
Single gas or Multi-gas monitors
Monitoring badges worn by employees
Fixed monitors
continuously measure the air
alarms that can be seen and heard when set points are exceeded
Coated strips that change color when exposed to specific gas / vapor of interest
Colorimetric detection tubes

7. Your Air monitors
MSA Altair 4 & Altair 5

8. Your Air monitors

9. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors

10. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors
Press the power button

11. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors
Press the power button
Meters run through start up sequence
Fresh air setup (FAS)

12. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors
Press the power button
Meters run through start up sequence
Fresh air setup (FAS)
Zero’s the sensors – must be in fresh air
Push the power button to enter FAS
Meter Calibration

13. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors
Press the power button
Meters run through start up sequence
Fresh air setup (FAS)
Zero’s the sensors – must be in fresh air
Push the power button to enter FAS
Meter Calibration
Needs to be done periodically and follow procedures
Bump test

14. Tell me about using these monitors
Your Air monitors
Tell me about using these monitors
Press the power button
Meters run through start up sequence
Fresh air setup (FAS)
Zero’s the sensors – must be in fresh air
Push the power button to enter FAS
Meter Calibration
Needs to be done periodically and follow procedures
Bump test
MSA has procedures using calibration gas, any field checks?

15. Air Monitoring – Check All Levels
Your Air monitors
Air Monitoring – Check All Levels
Different gases can be found at different levels
Methane:
Ammonia:
Carbon Monoxide: 0.96
Nitrogen:
Air: 1.0
Hydrogen Sulfide: 1.2
Carbon Dioxide:
Gasoline:
Jet Fuel, JP-8:
Lighter than air
Heavier than air

16. Sampling Methane (lighter than air) Carbon Monoxide (same as air)
Hydrogen Sulfide
(heavier than air)

17. Hazard Identification
What to look for – JSA
Hazard Identification
A “hazardous atmosphere” can exist in almost any place. What do you look for?

18. Where do these hazardous atmospheres exist?
What to look for – JSA
Where do these hazardous atmospheres exist?
Oxygen content below 19.5% or above 23.5%
Flammable gas, mist or vapor
Toxic atmospheres

19. You have set procedures for:
What to look for – JSA
You have set procedures for:
Confined space entry
Excavations
Hot Work --- Working around tanks, pipelines, well heads, etc
What about other areas – just because you know, have heard or aware enough to be thinking ahead
JSA

20. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmospheres – Oxygen Deficiency
A reduction in oxygen is caused by tank rusting, microbe activity, or replacement by another gas.
Lack of oxygen can cause a person to immediately collapse and die.
Normal air contains 21% oxygen. A space with oxygen content below 19.5 % is considered “oxygen deficient”.
19.5%
21% 0%
Oxygen content
Oxygen deficiency exists

21. Hazard Identification
What to look for – JSA
Hazard Identification
Effects of Oxygen Deficiency
% Oxygen Symptoms
19.5% - 16% Fatigue, mild impaired coordination
16% - 12% Increased breathing rate and pulse; impaired coordination, perception or judgment
12% - 10% Further increased breathing rate, blue lips, mental confusion
10% - 8% Fainting, nausea, vomiting, mental confusion within few minutes
8% - 6% Collapse, death within 8 minutes
6% - 0% Coma within 40 seconds, death
Using an “inerting gas” like nitrogen, to counteract flammable vapors will result in an oxygen deficiency.

22. Suspect O2 Deficient When:
What to look for – JSA
Suspect O2 Deficient When:
A space has been closed up or sealed
Has contained an inert atmosphere or has been purged
Contains water and organic material
Inside has can be rusting - Metal Oxidation
Combustion processes inside or close by
Contains or been involved with coatings, sludge, waste organics/water, materials that cure and/or absorb oxygen (such as has activated charcoal)

23. Dangers of Low Oxygen Levels
What to look for – JSA
Dangers of Low Oxygen Levels

24. Hazard Identification
What to look for – JSA
Hazard Identification
A word about oxygen-enriched atmospheres
A confined space with oxygen amount above 23.5% is considered “oxygen-enriched”.
The source of extra oxygen is typically from leaking oxygen cylinders used for oxy-acetylene torches.
Oxygen above 23.5% is a fire or explosion hazard.
Green tanks contain oxygen

25. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmospheres – Flammable Gases,
Vapors and Dusts
Flammable gases, vapors or dusts will ignite from a spark or flame if above a level in the air called the “lower flammable limit” (LFL).
Gas or vapor levels higher than 10% of the LFL are considered hazardous and the confined space cannot be entered until levels are reduced.
Amounts above 10% of the LFL are usually toxic as well.
Flammable atmospheres can include methane, or vapors in fuel storage tanks. Certain dusts like grain or flour are also flammable.
LFL is sometimes called “LEL” – “lower explosive limit”

26. Hazard Identification
Example of flammable gas levels - Methane
Air
100%
Air 0%
Too Lean
Too Rich
Boom!
Methane 0%
Methane
100%
Hazard still exists above UEL
5.3%
LFL
15.0%
UFL
An open flame or a spark will cause an explosion when methane amount is between 5.3% and 15%, the upper flammable limit (UFL).

27. Flammable Atmospheres
What to look for – JSA
Flammable Atmospheres
Non-flammable
(Too “Rich”)
Flammable
Flammable
Region V A P O R
Non-flammable
(Too “Lean”)
Temperature

28. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmospheres – Toxic Chemicals
At very high levels, most chemicals in the air can be immediately life-threatening or cause permanent bodily harm.
At lower levels, chemicals in the air can still cause harm.
PEL
Most chemicals have “permissible exposure limits” (PELs) which will cause harm if exceeded.
Even non-toxic or low-toxic chemicals can replace oxygen if levels are high enough.

29. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmosphere – Toxic Chemicals
The most common toxic chemicals in confined spaces fatalities are hydrogen sulfide and carbon monoxide.
Other toxic chemicals can include welding fumes, vapors from liquid residues in storage tanks, or chemical products used in the confined space.
Chemicals can quickly reach toxic levels in the air of a confined space, especially gases, solvent vapors or sprayed products.

30. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmospheres–Hydrogen Sulfide (H2S)
Hydrogen sulfide gas is commonly found in sewers or bottoms of tanks.
It can be instantly fatal at higher levels in a confined space. 30
100
200
600
1000
2000
H2S in parts per million (ppm)
Smell strong odor
Loss of smell
Coughing,red eyes
Unconscious in 30 min.
Death in minutes
Instant collapse

31. Hazard Identification
What to look for – JSA
Hazard Identification
Hazardous Atmospheres – Carbon Monoxide (CO)
Carbon monoxide comes from operating internal combustion engines in or near confined space.
Propane-powered engines also emit carbon monoxide.
Fatal levels of CO are quickly reached in confined spaces or low lying areas without air movement.
The PEL for CO is 35 ppm.

32. Your air monitor alarms – now what?
What to do if there is a problem
Your air monitor alarms – now what?
Should have addressed alarms in the JSA
When an alarms sounds you should have already planned the “What to do now!”
Depends on what you are doing
You and co-workers leave the area ASAP
Does the operator have a procedure in place?
Do you have a co-worker “down”
You are most likely not trained or set up to rescue
If you are watching your monitor, you should responded before there is an emergency.

33. Ventilation Natural - Mechanical – Not always dependable
What to do if there is a problem
Ventilation
Natural -
Not always dependable
Watch the wind socks
Look at topography
Mechanical –
preferred, positive hazard reduction
depends on configuration
consider nature of atmospheric hazard
Lab Safety Inc., Janesville WI. Used with Permission
Lab Safety Inc., Janesville WI. Used with Permission

34. Ventilating Confined Spaces
What to do if there is a problem
Ventilating Confined Spaces

35. Ventilation must be continuous or the hazard will return
What to do if there is a problem
Ventilation must be continuous or the hazard will return
What can you do to control the hazard ?

36. Questions?