Information About Multi-Gas Meters

[firemoose827 324]

I was tasked with assisting a retired chief of our department look into and get quotes for a Multi-Gas meter for our small department. With the threat of Chemical Suicides hitting close to home, and the increase in CO calls all over the county, we decided its time to research the different units and purchase one that will work for us.

Being a Haz-Mat Tech and a member of the county response team, we used the Multi-Rae Detectors but the ex-chief found out that there are issues with them? I have never had an issue with the one for our county team but will respect the wishes of our department and go with what they want as a body.

So, if anyone could offer input on the meters you use in your departments, pro's, con's, and stay away froms that would be greatly appreciated.

Thanks in advance!

Moose

[JohnnyOV 2]

I was tasked with assisting a retired chief of our department look into and get quotes for a Multi-Gas meter for our small department. With the threat of Chemical Suicides hitting close to home, and the increase in CO calls all over the county, we decided its time to research the different units and purchase one that will work for us.

Being a Haz-Mat Tech and a member of the county response team, we used the Multi-Rae Detectors but the ex-chief found out that there are issues with them? I have never had an issue with the one for our county team but will respect the wishes of our department and go with what they want as a body.

So, if anyone could offer input on the meters you use in your departments, pro's, con's, and stay away froms that would be greatly appreciated.

Thanks in advance!

Moose

Since you're in a rural part of the county, and I'll assume you have a very small operating budget, consider purchasing a Drager multi gas detector. Their sensors last 5 years, as compared to other companies 1.5 years. They are also very easy to use and work very well. It is what we use at work to test for toxic gases in the labs.

We use the Scott 4 gas meter in the FD which requires calibration every 30 days, and a sensor replacement every 1.5 years.

[FiftyOnePride 100]

We use the M40 Multi-Gas Detector. Meters 02, LEL, H2S, and CO, this came on recommendation from Mount Vernon. Great meter, easy to calibrate, have not had an issue yet. Comes with a multitude of clips for almost any application. Rugged and easy to use. Price is in the ~$700-$800 range. Well worth it, we budgeted for a second one next year.

[lalautze 35]

We have two types of 4-Gas Meters in service, two MSA Solaris and six RKI GX-2001.

The MSA take a couple minutes to go through their start-up procedure but we have not had to replace sensors very often. They do not give accurate readings when the O2 sensor goes out which was a concern and part of the reason we switched to the RKI. I do not remember what we paid for them.

The RKI are what the department has been buying lately. They run $800 each and I seem to have to replace the O2 sensors every eight to twelve months at $100 a piece. We have a calibration station so we are able to do the repairs in house and I've started a detailed log to document how often I'm replacing sensors and how much money we are putting into these. These meters only have a 30 second start-up and do not reference the other readings off of the O2 sensor so I still get accurate CO, LEL, and H2S readings even when the O2 sensor is offline.

We recalibrate ours whenever a sensor is replaced or once a year.

The other city departments (streets/public works & water) use the RKI GX-2009 which we service and calibrate as needed (ie. when they are broken and come to us).

I'm not sure that we will be changing meter brands anytime soon but hope this information helps.

[Fireman488 57]

Since you're in a rural part of the county, and I'll assume you have a very small operating budget, consider purchasing a Drager multi gas detector. Their sensors last 5 years, as compared to other companies 1.5 years. They are also very easy to use and work very well. It is what we use at work to test for toxic gases in the labs.

We use the Scott 4 gas meter in the FD which requires calibration every 30 days, and a sensor replacement every 1.5 years.

We use Drager 4 gas (Carbon Monoxide, Oxygen, Methane, and Hydrogen Sulfide) meters and Drager single gas personal CO meters. They are very reliable.

We do our own simple calibrations every 180 days. The customer service is excellent; and as mentioned above they are affordable.

[firemoose827 324]

Thanks for all the tips so far everyone. The main reason we need a meter is the CO calls we are getting lately in our area. The only decent meter is the one the Fire Coordinator has so he has to respond to all CO calls.

The second reason is the natural gas pipeline running through our district that covers the whole northeast. We have a transfer/pump station in our town also where we had a tour and a little informational lecture from some of the engineers there, and they told us that they sometimes pump other gasses through the line also. They said they dont know what is going through at any time some times and that concerned us. Anyone hear of the Blenheim Pipeline explosion in the 1980's from my county? The same kind of pipeline but from a different company.

Thirdly is the fact that we had 3 chemicaly assisted suicides in the surrounding area in the past few months. Thats scary enough. We just want a handheld 4 gas meter, and our budget will probably be up to $900, maybe more depending on a few fundraisers we have planned.

We are also looking to get a thermal imager too hopefully since we still dont have one of those either, but thats another whole battle we need to fight with the commisoners and then the public at the referendum.

Thanks again for the info, Im passing it on to the next meeting. Anyone else have any more?

[Bnechis 3,961]

We use the Scott 4 gas meter in the FD which requires calibration every 30 days,

We recalibrate ours whenever a sensor is replaced or once a year.

We do our own simple calibrations every 180 days.

30 days, 180 days 365 days whats the correct answer?

WARNING: WITHOUT PROPER CALIBRATION YOUR GAS DETECTOR IS AS EFFECTIVE AS CARRYING A BRICK.

Every book on direct reading gas detectors lists bumb testing or calibration before every use. Many state that calibration should be done no more than every 30 days unless bump testing is done before each use. Check your manufacturers info, most also say the same.

You are sending your personnel into a potentially toxic, colorless, odorless gas and the only thing that will save their life is a working detector.

Do you check how much air is in your SCBA or do you just hope its full?

OSHA

Carbon Monoxide In Workplace Atmospheres

(Direct-Reading Monitor)

3.a. Calibration

3.1.a. According to the manufacturer, "calibration must be performed at least on a monthly basis to keep the Model 190 Datalogger within published specifications"; however, for OSHA enforcement purposes, calibrate each time the monitors are used.

Verification Of Calibration for Direct-Reading Portable Gas Monitors

OSHA Link

Gas monitoring instruments are designed to protect personnel from unseen hazards that may exist in workplace environments, including confined spaces. It is vital to worker safety that these instruments are maintained and calibrated properly.

Instrument inaccuracy due to improper or irregular calibration can lead to serious accidents. Exposure to excessive levels of toxic gas or an oxygen-deficient environment can cause workers serious illness and even death. Combustible gas explosions are often catastrophic, injuring or killing personnel and destroying property.

The International Safety Equipment Association (ISEA), founded in 1933, is a trade association for manufacturers of protective equipment, including environmental monitoring instruments. The ISEA recommends, at a minimum, verification of sensor accuracy before each day’s use.

The only way to guarantee that an instrument will detect gas accurately and reliably is to test it with a known concentration of gas. Exposing the instrument to a known concentration of test gas will show whether the sensors respond accurately and whether the instrument alarms function properly.

If the instrument’s reference point has shifted, the reading will shift accordingly and be unreliable. This is called "calibration drift" and it happens to all detectors over time. An instrument that experiences calibration drift can still measure the quantity of gas present but it cannot convert this information into an accurate numerical reading. Regular calibration with a certified standard gas concentration will update the instrument’s reference point, ensuring that the instrument will produce continued, accurate readings.

In the past, there often has been confusion regarding proper calibration procedures and frequency. To clarify this issue, the International Safety Equipment Association (ISEA) issued a position statement on instrument calibration that states, "A bump test or full calibration of direct-reading portable gas monitors should be made before each day’s use in accordance with manufacturer’s instructions, using an appropriate test gas." If the instrument fails a bump test, it must be adjusted through a full calibration before it is used.

[Bnechis 3,961]

They do not give accurate readings when the O2 sensor goes out which was a concern and part of the reason we switched to the RKI.

These meters only have a 30 second start-up and do not reference the other readings off of the O2 sensor so I still get accurate CO, LEL, and H2S readings even when the O2 sensor is offline.

Most meters the toxic sensors: CO, H₂S, CO², etc. will work without the O² sensor.

Some detectors the LEL (or Meth sensor) will "read" without a working O² sensor others will not, however you had better understand how LEL sensors work.

LEL sensors "burn" a small sample of gas to determine how much is present. If there is a lower level of O² it can not "burn" the sample and the reading will be wrong. Many fire service book listed that before using a combutible meter always test for O² 1st. Those detectors that wont do LEL without the O² sensor are a safety, since most responders still have major problems understanding how detectors work.

[antiquefirelt 994]

We run both ITX 4 gas and MSA 4 gas/PIDs. Our personnel perform bump tests before any meter is used in the field. Cal gas is available with the meters to perform calibration as required. Every meter is powered and fresh air zeroed each morning and immediately calibrated as needed. Our Haz-Mat Officer maintains a calibration log and each meter is calibrated per the manufacturers schedule as well.

As was very well noted above, not ensuring your meters are properly calibrated should be unthinkable. The issue is what people "think" is proper vs. what they know. Don't think you know the proper way, know you know it.

[firemoose827 324]

30 days, 180 days 365 days whats the correct answer?

WARNING: WITHOUT PROPER CALIBRATION YOUR GAS DETECTOR IS AS EFFECTIVE AS CARRYING A BRICK.

Every book on direct reading gas detectors lists bumb testing or calibration before every use. Many state that calibration should be done no more than every 30 days unless bump testing is done before each use. Check your manufacturers info, most also say the same.

You are sending your personnel into a potentially toxic, colorless, odorless gas and the only thing that will save their life is a working detector.

Do you check how much air is in your SCBA or do you just hope its full?

Thank you Cap, I saw the differences in calibration intervals but I went to the web sites for each monitor and printed info from the site. I basically asked for what type of monitors worked for everyone and for each to give pros and cons.

Thanks everyone