Tackling Hydrogen Safety in Battery Rooms: Are Safety and Operations Managers Doing Enough?
For over a century, lead acid batteries have dominated uninterruptible power systems, and for a good reason. They’re low-cost, durable, reliable, and easy to charge. From data centers to forklift operations, several industries still heavily rely on these rechargeable batteries for disruption-free service.
However, lead-acid batteries are usually housed in enclosed battery rooms, where they routinely release small amounts of hydrogen during charging and discharging.
Due to the colorless, odorless, and highly flammable properties of Hydrogen, battery rooms require specialized safety precautions to mitigate risk to the workforce and infrastructure.
Today, we will explore these unique hydrogen safety challenges in battery rooms, the most common oversight committed by organizations, and how best to mitigate these risks.
Safety Challenges of Hydrogen in Battery Rooms
Unlike fertilizer, petrochemical, and power generation applications, where it plays a central role, hydrogen in the battery room is simply a by-product of the charging cycle. It’s vented by flooded lead acid, nicked cadmium, and valve-regulated lead acid (VRLA) batteries when their charge exceeds 80%.
During charging, the batteries produce hydrogen and oxygen during electrolysis in an electrolyte solution of sulfuric acid and distilled water.
Because hydrogen production isn’t the goal of battery room operations, some managers make the mistake of not monitoring it. And this is a considerable safety hazard. Here’s why:1. High Flammability:
Hydrogen is highly combustible with very low ignition energy, and something as small as an electrostatic spark from a human is enough to ignite it. It’s also flammable over a wide concentration range of 4% to 75% in air.2. Hard to Detect:
Hydrogen is odorless, colorless, and tasteless, making it extremely difficult to detect by human senses. For safe battery room operations, the deployment of hydrogen-specific sensors is crucial.3. Leaks Easily:
Because it’s the smallest atom in all the naturally occurring atoms, hydrogen leaks easily, and when it does, it travels faster than sound. It’s also 14 times lighter than air and rises upwards, forming explosive pockets near ceilings and roofs in a battery room.
What’s Holding Back Battery Room Managers from Focusing on Hydrogen Safety
Hydrogen is listed as a class 4 flammable substance, the highest rating according to National Fire Protection Association (NFPA) 704 standards. Material safety data sheets of lead acid batteries also mention the flammability of hydrogen and its potential to form explosive mixtures in the air.
The loss of hydrogen through outgassing also impacts the performance of a battery by deteriorating the quality of electrolytes. To add to the woes - a single bad battery can make other batteries go bad as they are typically connected in series or parallel configurations in most battery rooms. A faulty battery can trigger an imbalance in the charging or discharging process for all the other batteries connected to it, reducing their lifespan.
Even with safety and efficiency at stake, there’s still a lack of proactiveness in protecting battery rooms from hydrogen leaks.
Our industry experience and interactions have helped us narrow down the top reasons why hydrogen safety in battery rooms is typically overlooked:
1. Low Awareness of Safety Standards and Codes
Even though hydrogen is highly combustible, we can use some of its properties to our advantage where workspace safety is concerned. It diffuses rapidly, is non-toxic to humans, and doesn’t pose a major risk as long as it’s below a concentration level of 4%. Thankfully, there are several national and international standards and codes that make it safer to deal with hydrogen - IEEE Standard 450, NPFA Article 64, NPFA 2 Hydrogen Technologies Code, Uniform Building Code Section 6400, National Electric Code Section 480.9, and IS/IEC 600079-29-2: 2007.
These standards emphasize the importance of adequate ventilation and continuous hydrogen monitoring and alarm systems to limit H2 build-up from reaching 1% of the total volume of the room - far below the flammable level. However, there’s a clear need for training programs to make the owners, managers, and workers aware of these guidelines and encourage them to modify their facilities accordingly.
2. Reluctance to Invest in Sensing Solutions Due to High Costs
The high cost of hydrogen sensors is another factor that keeps managers from buying the adequate quantity necessary for safe coverage. The short life of sensors and associated maintenance costs also add to the skepticism. Some sensors are also unable to withstand high levels of hydrogen exposure.
However, the right sensor and sensing partner can do wonders in enhancing a battery room’s overall safety while reducing operational costs.
3. Lack of Guidance on Optimal Sensor Placement
Managers that do decide to invest in hydrogen sensors for battery rooms end up getting disappointed with the lack of guidance on deployment from the sensing solution provider. For instance, did you know it’s not a good idea to mount sensors on the false ceiling as hydrogen travels further up and pools at the top?
For more such dos and don’ts, a reliable sensing organization with deep industry expertise can make all the difference. To maximize their ROI, organizations should opt for sensor companies that provide end-to-end solutions, including a deployment plan along with the ideal number of sensors and vulnerable placement points for the highest safety coverage.
You can’t stop lead-acid batteries from releasing hydrogen, as it’s a normal part of battery charging. Hydrogen only becomes problematic when it accumulates and concentrates in pockets, making it an explosive risk.
However, since the primary job of battery rooms is to supply backup power, addressing hydrogen risks takes a backseat. We are here to change that by making sensing more accessible and cost-effective.
Our low-cost sensors are ultra-compact and detect hydrogen with exceptional accuracy at 1ppm level, making them ideal for battery room applications. Due to their small size and high sensitivity to hydrogen, our sensors can trigger early alarms, allowing enough time for operations managers to act. This not only makes battery rooms safer but also reduces operational costs by preventing premature battery failure.
Learn more about the industry’s best practices, safety standards, and the 21 Senses advantage in our follow-up blogs on battery room safety.