*The issue with Natural gas is mostly supply pressure and supply demand.
Most Natural Gas installations provide a very low supply pressure. The Natural gas regulator in the M360 Natural Gas instrument is designed to work with low pressure input. Set up correctly the instrument can work to specification with a Natural Gas supply. However, because of the flows and pressures involved it does not take much to upset the situation.
For example; when we test natural gas instruments, everything can be working fine but if, whilst preforming a precision test, the gas heating fires up then the supply pressure/flow to the flame photometer drops and the values returned for the next few analyses will be low by some percentage points. Conversely, if the boiler was alight when the instrument was blanked and calibrated but switches off whilst we are running a precision test; the results will increase dramatically.
The effect, if there is one, will be unique to the customer’s site/gas installation and the magnitude of such changes, we cannot quantify without being present – but they will be obvious if they occur during a precision test. What you may need to be wary of is; that you could install the instrument – run all your initial tests – and observe no problems. However, it is possible in subsequent days that an operator could subsequently suffer some issues with fluctuations in results.
You would need to consider what other items are connected to their natural gas supply. We suggest you then get the M360 lit, blanked and then have a 1ppm Potassium solution in a beaker being aspirated into the flame with the display set to 100. We would then switch on the other items connected to the Natural Gas supply and see if the display changes significantly away from 100 as a result. If it does, you would then need to consider whether the M360 could be run and all the results achieved in a certain time period when the other device(s) could be left off or on, If not, you could discuss whether it is acceptable to write into your analytical procedure; that if another natural gas consuming device has to be switched on or off during an analysis session then there will be a requirement to recalibrate the Flame Photometer. If those things can’t be accommodated, then you may have to consider an alternative gas installation – maybe one dedicated solely to the flame photometer?