CARE AND HANDLING
The Penetrometer should be handled with respect and care. If looked after properly,
it will operate for many years without problem.
CAUTION
Never push the Penetrometer guage needle over the 104 bar (1500psi)
reading on the gauge, as it will result in damage to the instrument!
SAFETY
The tapered tip is very sharp and should be removed when not in use.
CHECKING THE GAUGE FOR ACCURACY
Should you doubt the accuracy of the gauge at any time, you can check the reading on your
bathroom scales.
1. Place a small wooden block between the Penetrometer tip and the platform of the
bathroom scales.
2. Push the compaction meter downwards until the scale reads 20kgs (93 pounds).
3. The Penetrometer gauge should now read 20 bar (600 psi).
WHAT IS COMPACTION?
Soil is comprised of mineral or organic soil particles with spaces in between called “pore
space”. This space contains varying amounts of air and water depending on soil type and
conditions. The ratio of particle to pore space would ideally be 50:50 in natural un-
compacted friable soils.
However in soils which are supporting sports turf the reality is very different! The modern
demands of continuous play and the regular use of machinery, often in wet and highly
unfavourable conditions, is very destructive to soil structure and results in the condition
described as “compaction”.
Compaction starts at the surface and builds progressively throughout the soil profile often to
considerable depths preventing water penetration and the movement and up-take of all
essential elements. As the soil particles pack closer and closer together pore space is
eliminated and the soil is devoid of air and water, thus denying grass plants the “essentials of
life”.
USA research has demonstrated that soils compacted to levels measuring over
300 psi can seriously inhibit root development. However, it is not unusual to find compaction
levels of 600-800 PSI in sports turf including golf greens.
USING THE PENETROMETER
To use the Penetrometer, the operator should stand with his/her feet at approximately
shoulder width apart and with his/her hands placed on the handle bar grips.
By pushing down on the bar slowly and evenly, the operator can observe soil compaction
rates at all levels by reading the measurement scale on the pressure gauge in either Bar or
psi.
