---
type: Sensor Reference
title: "SNMP Humidity & Airflow OIDs (ENTITY-SENSOR Reference)"
description: "The SNMP OIDs for humidity and airflow — percentRH and cmm sensor types via ENTITY-SENSOR-MIB and environmental gateway MIBs, with a snmpwalk example."
resource: "https://snmp-monitoring.info/sensors/humidity-airflow/"
tags: [sensors]
timestamp: 2026-07-11T00:00:00Z
---

# SNMP Humidity & Airflow OIDs (ENTITY-SENSOR Reference)

The SNMP OIDs for humidity and airflow — percentRH and cmm sensor types via ENTITY-SENSOR-MIB and environmental gateway MIBs, with a snmpwalk example.

## Related concepts

- Up: [SNMP Sensors & OID Catalog: Every Metric You Can Monitor](/sensors/index.md)

## Frequently asked questions

### What OID is humidity in SNMP?

The portable one is entPhySensorValue (1.3.6.1.2.1.99.1.1.1.4) from the ENTITY-SENSOR-MIB, for any sensor whose entPhySensorType is percentRH. In practice, most server-room humidity comes from a vendor environmental gateway's enterprise MIB under 1.3.6.1.4.1, which you poll instead of the probe directly.

### What unit is airflow reported in?

The ENTITY-SENSOR type for airflow is cmm — cubic metres per minute, a volumetric flow rate. It's read like any other sensor (value with scale applied) and is most useful for hot-aisle/cold-aisle context, where falling airflow signals restricted cooling before temperature rises.

### What MIB has humidity sensors?

The standard ENTITY-SENSOR-MIB (1.3.6.1.2.1.99) types humidity as percentRH. But most room humidity is delivered through a vendor environmental gateway — APC NetBotz, HWg, Sensaphone — via its own enterprise MIB under 1.3.6.1.4.1, so the OID you use is often vendor-specific.

### How do I read a room probe?

Point your manager at the environmental gateway the probe plugs into, walk its vendor subtree (or the ENTITY-SENSOR table if it uses the standard objects), and apply the sensor's scale and precision to the raw value. Load the vendor MIB so names and units resolve rather than reading bare integers.

## Source

Concept generated from https://snmp-monitoring.info/sensors/humidity-airflow/ — the SNMP Monitoring vendor-neutral knowledge base. Content is limited to what that page states (no external claims added here).