How do i calibrate thermometer without having an already calibrated one in the first place?

[Josh7182]

Sorry if this has been asked before, but I tried to scroll many posts here and couldnt find an answer. How do I calibrate a thermometer if I dont already own a calibrated one? My digital thermometer says 38.0 but my oral thermometer says 38.0. Should I get a mercury thermometer and calibrate it using that? I've read about taking boiling readings and taking ice water and calibrate it using that? But some people are against it while some claims it works. So I'm really confused in what I should do.

 

[aart]

You can dink around with various techniques,
https://www.backyardchickens.com/ar...incubator-thermometers-and-hygrometers.73634/

but I'd strongly suggest you buy one of these and never look back.
https://www.thermoworks.com/RT301WA

 

[Josh7182]

You can dink around with various techniques,
https://www.backyardchickens.com/ar...incubator-thermometers-and-hygrometers.73634/

Thanks, not sure if I understood it properly but you can calibrate other thermometer against oral? Or do I need to calibrate the oral thermometer first?

but I'd strongly suggest you buy one of these and never look back.
https://www.thermoworks.com/RT301WA

To be completely honest, I'm just trying out a hatching experiment with my family to see some eggs turning into chicks so if possible I don't really want to spend much where possible

 

[45lk9p459gm-w]

The standard is to mix crushed ice with water and let it stand for 15 minutes. Then stick the bulb of the thermometer into the water and let it set for a few minutes. Calibrate the reading to 32 degrees if needed and you're done.

Ice water works better than the boiling water method. True water boils at 212 degrees but you can still put more heat into the water if you turn up the fire. With ice water it is 32 degrees period. Unless you stick in back into the freezer or something.

 

[aart]

not sure if I understood it properly but you can calibrate other thermometer against oral?

You compare them, oral therms are often the most precise, but need to look at their tolerance(printed on package).

Using ice water is really not accurate as oral, and most brooder therms, are not meant to register that low of a temp.

Food therms have a range that can be checked with ice water and boiling water,
tho you need to find the boiling temp of your elevation.

 

[Josh7182]

You compare them, oral therms are often the most precise, but need to look at their tolerance(printed on package).

Okay thank you. The thing is I'm using one which i dont have the packing anymore

Using ice water is really not accurate as oral, and most brooder therms, are not meant to register that low of a temp.

Food therms have a range that can be checked with ice water and boiling water,
tho you need to find the boiling temp of your elevation.

Would you recommend I get another mercury thermometer or a food therm and calibrate it against ice? Or get another oral thermometer and know the accuracy and calibrate my digital thermometer with it?

 

[aart]

Would you recommend I get another mercury thermometer or a food therm and calibrate it against ice? Or get another oral thermometer and know the accuracy and calibrate my digital thermometer with it?

but I'd strongly suggest you buy one of these and never look back.
https://www.thermoworks.com/RT301WA

 

[Josh7182]

Okay thanks but if you dont mind me asking which should I get amongst the ones I mentioned bcs it is just a fun project that I dont intent to spend alot on and if it doesnt work it it doesnt really matter? So among the ones I mentioned which is the best option ? @aart

 

[aart]

Okay thanks but if you dont mind me asking which should I get amongst the ones I mentioned bcs it is just a fun project that I dont intent to spend alot on and if it doesnt work it it doesnt really matter? So among the ones I mentioned which is the best option ? @aart

The one I recommend is a food thermometer.
Even if you don't continue to hatch, it's great in the kitchen too.

 

[Josh7182]

Okay, so when I get the food one I should calibrate by checking the boiling temp and the ice bath correct?