When sampling for indoor air, it is recommended to use the following guide to estimate how many samples are required. The objective is to cover the square footage of the area being sampled.
up to 1,500 sq ft 1-2 air samples
1,500-5000 sq ft 2 samples
5001-10,000 sq ft 3 samples
10,000- 20,000 sq ft 4 samples
20, 000- 50,000 sq ft 5 samples
50,001- 250,000 sq ft 6 samples
250,001- 1,000,000 sq ft 7 samples
>1,000,0001 sq ft 9 samples