There seems to be a number of websites where the Bacharach fyrite apparatus and/or supplies are supposed to be available. Amazon lists a fyrite analyzer refill kit for $147.60. I mention this in case this proves helpful until an alternative method is available to you. To answer your question, a number of companies use the Thermo Fisher Scientific, item #50121515, which is supposed to be very reliable and way easier to use than the traditional fyrite. It is quite expensive (~$4.700), and it needs to be factory calibrated annually, which is also expensive. To my surprise, the Thermo Scientific website states ”The product 50121515: IR Gas Testing Equipment with Travel Case is not orderable in your country at the moment. Please contact our Technical Support for possible alternatives.” However, it is available from Fisher Scientific UK for 3745.00 Euros. Some people use a very simple and cheap infrared gas analyzer like the model Sensair S8 analyzer (https://www.co2meter.com/products/004-0-0053-senseair-s8-low-power-co2-sensor).

Hello. I found the fyrite resale options, but it appears to be a short-term solution as the products have been discontinued. The $4700 is a bit outside my price range. I think the Sensair seems to be my best option. Thank you for the response.

Hi, Did you try something from Sensair as a replacement for the fyrite system. How is it working out? We are also currently looking for alternatives for fyrite to check our incubator 5% CO2 levels. Thank you. Rebecca