Static electricity risk is directly tied to relative humidity, but the answer is not simply “keep it above 40%.” This article breaks down the full RH spectrum zone by zone, showing what happens below, within, and above the recommended range and why both bounds matter for ESD control.

Ido Goldstein
Chief Technology Officer at Smart Fog
Author
Ido Goldstein is a technology innovator with deep expertise in humidity engineering, climate control, and non-wetting fog systems. He has spent years advancing energy-efficient and water-smart solutions that help industries like cleanrooms, data centers, wineries, and greenhouses maintain precise environmental control.
Passionate about technology with real-world impact, Ido also supports sustainable agriculture initiatives and nonprofit innovation. Through this blog, he shares practical insights on HVAC advancements, indoor air quality, and the science behind high-performing environments.
Dew Point in Cold Storage: Preventing Sweating & Ice
Uncontrolled dew point causes sweating surfaces, floor ice, evaporator blockage, and product spoilage in cold storage. This guide explains how dew point behaves across facility zones and what facility managers need to evaluate to prevent it.
Data Center Dew Point: ASHRAE Ranges & ESD Risk
ASHRAE TC9.9 defines specific dew point limits for data center environments, and operating outside those limits creates two distinct failure modes: electrostatic discharge at the low end and condensation at the high end. This article explains the class envelopes, the thresholds, and the operational risks at each boundary.
How to Prevent Condensation on Cold Surfaces
Condensation forms when a surface falls below the dew point of surrounding air. This guide covers surface-specific prevention methods including insulation selection, vapour barriers, surface heating, and ventilation, applied across pipes, windows, AC vents, and cold industrial equipment.
Wet-Bulb Temperature Explained
Wet-bulb temperature measures how much the air’s humidity limits the body’s ability to cool itself through sweating. This guide explains what it is, how it is measured, and why it matters for human health and industrial facilities.
RH Conversions: Relative Humidity to Dew Point & Absolute Humidity
Convert relative humidity to dew point temperature or absolute humidity using interactive calculators and the Magnus approximation formula. This guide covers conversion direction, worked examples, comfort thresholds, and when simplified formulas lose accuracy.
What Is Enthalpy in HVAC? (Moist Air Energy Explained)
Enthalpy of moist air is the total heat content of an air-water vapor mixture per unit mass of dry air, combining sensible and latent components. This guide defines the formula, walks through a worked example, and explains how HVAC engineers apply enthalpy values to coil sizing, AHU selection, and energy recovery.
Dew Point for Painting & Coating: The +5°F Surface Rule
Before applying any coating, surface temperature must be at least 5°F above the dew point temperature. This article explains the physics behind the rule, how to measure compliance in the field, and how substrate type and enclosed environments change the risk profile.
Why Is Temperature Control Alone Not Enough in Server Rooms?
Temperature management is essential for server rooms, but cooling alone does not protect against static discharge, condensation damage, or airflow failures. This guide explains the full set of environmental controls a server room requires and why each one operates independently of thermal management.
How to Read a Psychrometric Chart (Complete Guide)
A psychrometric chart encodes every thermodynamic property of moist air in a single diagram. This guide walks through each axis, curve family, and state point in sequence, then shows how to trace HVAC process lines and apply chart readings to real facility decisions.












