Data centers are being built across the Southeast at a pace nobody predicted five years ago, and every one of them depends on stored energy to ride through a power blip. That stored energy, whether it is lead-acid UPS batteries or lithium-ion energy storage, carries a gas hazard most facility teams underestimate. Getting gas detection right in these rooms is a code requirement, a life-safety measure, and increasingly a condition of the insurance and the build. This guide covers what gases actually matter, why, and how to think about specifying detection.
Why a data center has a gas problem at all
It is easy to think of a data center as just servers and cooling. But the part that keeps those servers alive during a grid event is a large bank of batteries, and batteries off-gas. There are two distinct hazards depending on the battery technology.
Lead-acid UPS battery rooms: hydrogen
Traditional UPS systems use lead-acid batteries, and during charging they release hydrogen. Hydrogen is odorless, lighter than air so it collects at the ceiling, and explosive at concentrations as low as 4 percent by volume. A battery room with inadequate ventilation can accumulate hydrogen to a dangerous level without anyone knowing. The standard safeguard is fixed hydrogen detection that triggers ventilation and alarms well before the lower explosive limit is reached.
Lithium-ion energy storage: thermal-runaway off-gas
Lithium-ion energy storage systems are increasingly common in and around data centers. Their failure mode is thermal runaway, a chain reaction in a damaged or defective cell that, once started, cannot be stopped. The valuable safety window is before it fully ignites: a failing cell vents electrolyte vapor and gases first. Detecting that early off-gas can buy time to act before a fire or explosion. The gases released during lithium-ion failure include carbon monoxide, hydrogen, hydrogen fluoride, and a mix of volatile organic compounds (electrolyte vapor).
What the codes require
This is not optional in most installations. Energy storage systems are governed by standards including UL 9540A (the test method for thermal runaway fire propagation) and NFPA 855 (the standard for the installation of stationary energy storage systems), which require or recommend gas detection in many configurations. Lead-acid battery rooms are covered by separate ventilation and hydrogen-monitoring requirements. The practical takeaway for anyone speccing a data center: gas detection in the battery and energy-storage spaces is usually a requirement, not an upgrade, so it belongs in the design from the start rather than bolted on later.
What to monitor, room by room
| Space | Primary gases | Why |
| Lead-acid UPS battery room | Hydrogen (H2) | Released during charging; explosive at 4% by volume; collects at ceiling |
| Lithium-ion energy storage (ESS / BESS) | CO, H2, VOCs, and per code HF | Early off-gas precedes thermal runaway; detection buys reaction time |
| Switchgear / transformer rooms | Combustible gas; CO where applicable | Arcing and overheating can off-gas; confined electrical spaces |
| Generator / fuel storage | Combustible gas (fuel vapor), CO | Backup generators and on-site fuel introduce hydrocarbon and exhaust risk |
The detail that trips people up: not every sensor sees hydrogen
Combustible gas detection uses two main sensor technologies, and the difference matters in a battery room. Catalytic bead sensors work by burning gas molecules on the sensing element, and they can detect hydrogen. Infrared sensors stay in calibration longer and offer self-test, but they cannot detect hydrogen, because hydrogen is not a hydrocarbon and does not absorb infrared the way methane or propane do.
Why this matters: if someone specs an infrared combustible sensor for a battery room expecting it to catch hydrogen, it will not. For hydrogen, the right choice is a catalytic bead or an electrochemical hydrogen sensor. This is exactly the kind of detail worth confirming with an application specialist rather than assuming, because the wrong sensor technology means the hazard you most need to see is the one you are blind to.
How GGC’s gas detection line fits
George Grant Company represents GDS Corp gas and flame detection, which manufactures fixed gas detection systems for toxic, combustible, and hazardous gases. The pieces relevant to a data center are:
- GASMAX II — a single or dual-channel gas monitor that supports any GDS Corp sensor, or a combination of one toxic and one combustible sensor, with an intelligent display and standard communications.
- GASMAX CX — a monitor built for applications where readings need to be transmitted in real time, with dual 4-20mA outputs and built-in Ethernet with MODBUS/TCP for integration into a building management or control system.
- GASMAX EC — a loop-powered two-wire detector for highly reactive gases in hazardous conditions.
GDS Corp offers both catalytic bead and infrared combustible sensors, plus toxic sensors including carbon monoxide and hydrogen, so a system can be configured for the specific gases in each room. The detectors output the industry-standard 4-20mA signal (or MODBUS) so they integrate with the facility’s existing monitoring rather than living as an island.
Five questions to answer before you spec
- Which battery technology? Lead-acid points you at hydrogen; lithium-ion points you at a multi-gas off-gas approach.
- What does the code require here? UL 9540A and NFPA 855 for energy storage; ventilation and hydrogen monitoring for lead-acid. Confirm the authority having jurisdiction’s expectations early.
- How many points, and where? Hydrogen collects high, so sensor placement near the ceiling matters; the number of detectors scales with room size and battery count.
- How should it integrate? 4-20mA into the existing system, MODBUS, standalone alarm, or tie-in to ventilation and shutdown. This drives the monitor choice.
- Who maintains and calibrates it? Gas sensors need periodic calibration; a sensor-exchange or calibration program keeps the system trustworthy over its life.
Get help speccing data center gas detection
George Grant Company represents GDS Corp gas and flame detection across Tennessee, Georgia, and Alabama, and our team supports gas selection, sensor technology, placement, and integration. If you are building or retrofitting a data center, energy storage system, or battery room and want the gas detection scoped correctly the first time, reach out and we will help you get it right.