In-situ relative humidity sensor for concrete slab testing
The probe that goes into the slab. It complies with ASTM F-2170, the standard method for measuring relative humidity in concrete floor slabs with in-situ probes, and it can also read ambient conditions — the sensor flooring contractors and inspectors use before a covering goes down.
Compatible meters
Important — fewer meters than the ambient sensor
The RH/T-S3 works with the HT-4000 and TotalCheck only. The RH/T-S1 ambient sensor additionally works with the Navigator Pro and QuickNav, but the S1 cannot do in-situ testing. If you own a QuickNav or a Navigator Pro and you need ASTM F-2170 results, talk to us before ordering — the meter is the limiting factor, not the sensor.
Specifications
| Part number |
RH/T-S3 |
| Type |
In-situ RH and temperature probe |
| Standard |
ASTM F-2170 |
| Also available as |
RH/T-S3/5, pack of five |
| Sold as |
Each |
What else the test needs
-
CS-3 sleeves — the plastic sleeve that lines the drilled hole. Required for the test.
- A rotary hammer and the correct bit for the sleeve diameter.
- Time. ASTM F-2170 requires the hole to equilibrate before the reading is valid — the sleeve is installed, capped and left. A reading taken too early is not a compliant reading.
Why relative humidity and not a surface reading
A resistance or scanning reading tells you about the top few millimetres of a slab. Flooring fails because of moisture deeper in, which migrates up once an impermeable covering goes down. In-situ RH at the correct depth is what flooring manufacturers ask for when a claim is made, and it is the reading that protects you.
Frequently asked questions
How many probes do I need?
ASTM F-2170 sets a minimum number of test locations based on floor area. Check the current edition of the standard for your slab, and buy sleeves accordingly.
Can I reuse the probes?
The sensor is reusable. The CS-3 sleeve stays in the slab.
How do I know the sensor is accurate?
Check it against the RH/TK/33 or RH/TK/75 salt solution kit. On a job where flooring is going down over your reading, do it before you start.
Can I extend it to read the meter more easily?
Yes — the RH/T-C1 gives 3 feet of extension.
Not sure which part fits your meter or electrode? Send us the model and what you are testing, and we will confirm the correct part before you order.
