Gas Meters 101

Gas detection equipment can be broken down into two categories:

• Fixed detectors - hard wired instruments typically installed in areas where flammable or toxic vapors are likely to be.  When these gases are detected, audible and visual alarms are activated. 
• Portable gas monitors - small monitors designed to be mobile. Often they are the size of a pager, radio or lunch box.  They include;
  • Single gas detectors - designed to detect one particular gas.  They can be a passive detector like a badge, a spot method of detection as with sample draw tubes, or a real time gas monitor that continually updates readings.
  • Multi gas meters - monitors several gases simultaneously and are usually configured for Oxygen, Combustible Gases and two toxic gases.  These are primarily used as confined space monitors. There are also instruments capable of 5 different sensors in varying configurations. 

Note: Some sensor technologies allow monitoring of an entire group of gases such as flammables or volatile organic compounds.  

Sampling Methods

• Diffusion - instrument simply monitors the atmosphere in your personal space.  These are often referred to as personal monitors and can be as small as a pager or credit card.
• Sample Draw - pump module draws the gas to the sensors for measurement.  Gas monitors with a sample draw pump are preferred when pulling samples from confined spaces, continuously monitoring a work area, or measuring for small trace amounts like in soil headspace measurements. 

Run Time

When you buy a gas meter, you’re purchasing the ability to safely do your job.  The gas monitor should be able to work for at least as long as you.  With today’s technology, rechargeable batteries run longer, recharge quicker and don’t need replacing as often. Consider an alkaline battery pack as a back-up.  Avoid NiCad packs which are prone to developing a “memory” and often require meticulous discharge cycles. The latest technology available is Lithium Ion batteries like the one in cell phones.

Ease-of-Use

Ease-of-use is the most important aspect of them all.  People simply won’t use a piece of equipment that they don’t know how to operate.  Be sure that the operation of the gas meter is easy to figure out.  Look for features such as training videos, live training sessions with the vendor and quick reference cards.  If the operation of the meter can be boiled down to a laminated card, most likely it will be easy to use.

Datalogging

1. Your safety.  Flammable and/or toxic gases can have a chronic and/or an acute affect on your health.  A chronic effect would be that you accidentally ignite a flammable atmosphere and cause an explosion.  An acute affect would be that for 20 years on the job you were exposed to levels of toxic gases that either cause cancer or significantly degrade the quality of your retirement years.
2. It’s the law. Different branches of the Government have established regulations designed to protect worker safety and the environment.  For example, in 1994 OSHA regulated Confined Space Entry putting in place the procedures necessary to do it safely. A gas meter is now a required piece of confined space equipment to meet the atmospheric testing regulations. 

What gases should I monitor?

Unless you have the training to make this determination, it may be prudent to consult with an Industrial Hygienist.  They can evaluate your facility and the processes for any potential gas exposures.  Once you know what your concerns are, we can assist with the selection of a gas meter that fits your needs and your budget.

Confined Space Gas Meter

By far, the most popular configuration for a confined space gas meter is O2/LEL/CO/H2S. If you know that you need to purchase a full set of equipment for confined space entry including gas detection, fall protection and ventilation equipment, you’ll be glad to see our Confined Space Equipment Kit page.  You can order everything you need with a single part number.   

Other configurations of multi gas meters are necessary when another specific gas is present.  For instance, a waste water treatment plant may need to monitor Chlorine, a power plant may need to monitor Sulfur Dioxide or a facility with refrigerated storage may need to monitor Ammonia.  We have the basic four gas meters and several different five-gas meters that can cover your custom configuration. 

How easy can it be?

• Nothing more to buy
• No additional maintenance cost
• Replacement of all consumable items including sensors at no charge
• Monthly calibration service 
• Documentation and  storage of the data files from the meter

 What you’ll get is a meter that’s always calibrated and ready to go.  Call us for details! 888.972.3389