Frequently Asked Questions
Here are the most common questions we're asked about BWB Flame Photometers. If you can't find the answers you need here, get in touch and we will try to get your questions answered quickly.
To filter your search to more relevant answers, use the search box provided below:
Filter results:
Yes, all elements can be calibrated at the same time using single or multiple calibration standards.
Can I calibrate all elements at the same time?
Calibration correction allows you to correct a calibration curve using just a Blank and/or the highest point within the curve. This helps to correct for drift.
What is calibration correction?
Drift can occur over the period of a day as environmental factors such as air temperature, humidity and barometric pressure change. The instrument employs the use of a live flame; a flame is affected by all of these factors and more, for instance, a higher humidity level means less oxygen in the air.
What is drift in relation to a calibration curve?
Multiple factors can cause drift, just a few include; air temperature, environmental pressure and humidity, sample head.
What causes drift?
This is the distance from the nebuliser to the top of the liquid sample being analysed. As the head increases the sample flow rate (aspiration rate) will decline marginally, it is strongly recommended to sample from broad sample cups rather than tall and narrow sample cups. We provide 100 disposable cups with every instrument to get you started and offer them for sale straight from stock.
What is meant by sample head?
This can be found in the technical data for the particular model, we suggest that in all cases, in order to maintain most consistent results and prevent a requirement for increased cleaning, you keep all concentrations presented to the flame below 100ppm. This can be achieved by calibration and sample dilution.
What is the detection range for each element?
In the majority of our models you can calibrate a curve with up to 10 points, in our BIO range (BIO, BIO-AV & BIO-943*) you can calibrate with up to 5 points of calibration. In both cases this excludes the Blank.
*USA market only
What is the maximum number of calibration points for a multi-point calibration?
All of our instruments include a gas detection module that detects (by ‘smell’) a gas leak, this is far more sensitive than the human nose and can alert you to small weeps that may otherwise go unnoticed. We also include flame detection via infrared analysis, safety gas cut off and low level detection in the waste cup*
*Not included on the Flash instrument range
What safety features are present on the instrument?
We offer the ability for gas adjustment in order to fine tweak the flame to set it to the optimum level, the average gas consumption rate is 0.155 Litres per minute.
What is the gas consumption rate and can it be adjusted?
We supply everything you need to use the instrument straight out of the box, excluding the gas. You can find a full list of everything included under the ‘in the box’ section on each product page. We supply all of the calibration standards relevant to the elements within each instrument and offer them ex-stock available for purchase to replenish your supplies.
What reagents do I need to purchase?
Yes, this is fitted to the instrument and we supply a gas hose (conforming to UK standards) to connect your gas source to the regulator, the regulator can be supplied with a maximum of 16 BarG.
Does the system come with a gas regulator?
There are quite a few differences between Flame AES and Flame AAS. Both introduce the ions into the flame where they are put in an excited state. With FES (also known as AES), as the excited state "relaxes" it emits light of a specific colour which is then detected. The more light detected the more ion is in the sample. With Flame AAS, the excited state will absorb certain colours. A white light containing all colours is passed through the flame and the excited ions will absorb certain colours. The degree of absence of those colours is a measure of the concentration in the sample.
What is the difference between Flame AAS and Flame FES?
Yes we do, our BIO instrument is supplied with mmol/L calibration standards, alternatively, these can be purchased individually or as part of a kit.
Do you have calibration standards in mmol/L ?
Multiple the mmol/L value by the atomic mass of the element, for example Lithium (Li) has an atomic mass of 6.94, if we had 10mmol/L of Li, this would equate to approximately 69.4ppm.
How do I convert mmol/L to ppm
It depends on what stage of the process you wish to measure. The actual biodiesel cannot be run through the flame photometer. However, if you’re interested in the waste portion to ensure that the Na & K have been fully flushed out then this would be possible. Many of these soap-like compounds are washed out with water, as long as the measurement is conducted towards the end of the final wash then analysis should be ok. Conducting the analysis too early through the wash period could lead to the soap-like compounds forming foam inside the mixing chamber and affecting the instrument stability.
Can we measure Na & K in Bio Diesel using your instruments?
Yes we do, we supply paper copies of all certificates of analysis with each of our calibration standards, in addition, further copies can be downloaded on demand from our online portal or customer portal.
Do you supply certificates of analysis with calibration standards?
You can download these from our website or though our customer portal.
How do I get copies of the calibration standards certificate of analysis?
Our specifications are designed to give a comparative assessment against competing brands, and allow for a variety of applications and methods of analysis. In some cases it is more than acceptable to sample solutions containing greater than 100ppm. We suggest, however, that samples are kept below 100ppm for 2 reasons:
1. Higher than 100ppm and the interferences between ions starts to become significant. This will throw off the results or will require matrix corrections when calibrating.
2. High concentrations of salts will build up in the mixing chamber/burner where they can come off sporadically causing an unstable signal. This then requires those parts to be cleaned very often, possibly several times a day, which is not very desirable for the user.
Why do your specifications state limits of analysis greater than your 100ppm recommendation?
Everything you mention about the environmental situation will affect the stability from air temperature to humidity and barometric pressure. Na will be the worst because there is a lot of Na in smoke, dust, exhaust and hair. The K is not quite as prevalent in the environment as Na and Li is not at all.
What environmental factors can affect the stability?
We strongly suggest using propane, typically most industrial grades are acceptable and a clinical grade is not required. Butane, however, is most preferred when conduction sample analysis for Barium only. All of our instrument from 2019 allow the operator to select the gas source from a choice of propane, butane and methane (natural gas / town gas) without any modification.
What is the recommended gas to operate a flame photometer?
Yes, you have the option of configuring the system to show a maximum of 1, 2 or 3 decimal places per element and each element can be configured differently. The decimal point will then auto range to your maximum setting based on the value of the sample. The ranges are as follows:
• 9.999
• 99.99
• 999.9
• 9999.9
Can I change how many decimal points are displayed?
Yes, all of our instruments allow for the operator to change the units of measure, the units will be updated on the next calibration. Please note that the instrument does not carry out any calculation when changing from one set of units to another, it is merely for display. The units can be selected from the following list:
• ppm
• mmol/L
• meq/L