Solvita Ammonia Calculator

Using Solvita to measure air-space ammonia

Solvita-Ammonia is a test with many possible uses, including to estimate the concentration of potentially hazardous ammonia (NH3) in any given space of air.

A calculator has been developed based on collaborative research with the University of Alabama poultry division, enabling Solvita to be used to test litter or building manure and to infer the air concentration of hazardous ammonia in the space above the litter.

The variables in this calculator are: depth of animal-litter (or manure, or compost) and the height of the building plus the Solvita test result.  One can enter air-exchange rate to determine what refresh rate will bring the building concentration into a safe level (generally less than 50 ppm).

The test may also be used for any stored organic amendment containing free ammonia (compost and pelleted manure).  Enter the depth of material until obtaining the correct volume of material (cubic feet).

Ammonia Calculator

Solvita Ammonia (NH3) Number, 0 to 5 color
Building Length feet
Building Width feet
Building Height feet
Depth of Material feet
Air Exchanges Per Hour
Total Building Volume
Material Volume
NH3 in Building
NH3 in Building, Adjusted for Air Exchange


What levels of ammonia are safe? Ammonia gas in poultry houses seriously affects the health condition of the birds.  Elevated levels of free ammonia have a negative impact on overall livability, animal weight gain, feed conversion, and the immune system of the birds. It also is known to affect High levels also have a negative impact on overall livability, weight gain, feed conversion, the rate of condemnation processing adding further economic harm.  Generally, broiler chickens should be kept in an environment with ammonia concentrations of less than 35 ppm.

In dairy operations, typical ammonia levels in well-ventilated, environmentally regulated farm buildings are 10 to 20 ppm such as with liquid manure removal systems and as high as 50 ppm where manure and urine are deposited on solid floors and only removed occasionally. At levels over 500 ppm there is likely to be immediate and severe irritation of the respiratory system..


The time-weighted average (TWA) for NH3 is 25 ppm (18 mg/m3) and the short-term (ST) exposure level is 35 ppm (27 mg/m3). ST is a 15-minute exposure. see: NIOSH DOC

OSHA Personnel Exposure Limits:

The standards promulgated by OSHA for workers have set the TWA at 50 ppm NH3 (35 mg/m3).

For more information call 207-293-2457. To order a Solvita® Ammonia Kit, . If your soil lab isn’t performing the Solvita® ammonia test, ask about it!