A lockout hasp can hold as many padlocks as it has lock holes. If you are asking how many padlocks can a lockout hasp hold, the direct answer is: the padlock capacity equals the count of lock holes on the hasp body. A 6-hole hasp accepts up to six personal locks, a 12-hole sliding hasp accepts up to twelve, and a 24-hole sliding hasp accepts up to twenty-four. For your business, that number is the practical upper limit of how many workers can independently lock out one energy-isolating point at the same time.
What often confuses buyers is that the jaw opening of the hasp has nothing to do with how many padlocks it holds. Jaw size only decides whether the hasp can physically clamp onto your valve, breaker, or switch. Keeping these two ideas separate is the first step to choosing the right model, and it is the distinction we build the rest of this guide around.
When you size a lockout hasp, you are really answering two different questions. Mixing them up is the most common cause of a wrong order.
The lock holes are the round openings around the hasp body where each worker threads their own padlock shackle. Each hole = one personal lock = one worker. The lockout hasp number of lock holes is therefore the single specification that defines padlock capacity.
The jaw is the curved clamp at the end of the hasp that wraps around the energy-isolating device. The lockout hasp jaw size must be large enough to pass over the valve handle, breaker body, or switch you are locking, but not so large that it cannot hold securely. A hasp with the right number of holes is useless if its jaw will not close on your equipment. Measure the actual isolating device before you order, not the pipe or panel around it.
In short: lock holes decide capacity, jaw size decides fit. A correct lockout hasp sizing decision treats both as separate checks rather than one number.
Knowing the lock-hole count is not enough. Each hole also has a diameter, and your padlock shackle must pass cleanly through it. If the shackle is thicker than the hole, workers cannot apply their lock; if the hole is far larger than the shackle, the fit feels loose and can be worked. The lockout hasp padlock capacity is only real if every worker’s lock actually fits the holes.
A common reference point is a 9 mm lock hole, but you should always confirm against the shackle diameter of the padlocks your crew actually carries on site. If you need to know how to choose a lockout hasp for mixed padlock brands, match the hole diameter to your thickest in-use shackle so no one is left out.
Below are the group hasp types most often specified for industrial buy lists, described only with specifications published on the product pages. These are the building blocks you will choose between.
The 6 hole lockout hasp is the workhorse of group LOTO. Prolockey offers it in three materials so you can match environment to duty: the steel SH01 (PA body, nickel-plated steel shackle, 9.8 mm holes, red), the aluminum AH11 (nylon body, aluminum shackle, ~9 mm holes, red, spark-resistant), and the double-end steel DSH01 (red sprayed steel, 11 mm holes, with two different jaw sizes on one body). Six holes cover most maintenance crews on a single energy point.
You may also search for an 8 hole lockout hasp. When your crew is larger than six, the practical step up is the 12-hole sliding aluminum hasp (AH31) or the 24-hole sliding hasp (AH32), rather than a dedicated eight-hole model. If you specifically need eight locks on one point, the 12-hole sliding hasp gives you that capacity with headroom to grow, which is usually the better long-term buy for your business.
A group lockout hasp is simply any hasp designed for multiple personal locks on one isolation point. Beyond the fixed six-hole bodies, the sliding aluminum hasps (AH31 at 12 holes, AH32 at 24 holes) let a long row of workers lock out along a single clamped jaw. They are useful when several trades converge on one piece of equipment during a shut-down.
Sometimes a single hasp runs out of lock positions, or the isolation point is awkwardly shaped and will not accept a hasp at all. In those cases, do not improvise by chaining unrelated locks or sharing one key. Two verified approaches are available.
First, you can pair hasps or move to a higher-capacity sliding hasp, as described above. Second, and often cleaner for very large crews, you can use a group lockout box such as the LK07. The LK07 is a 430-grade stainless steel box with 18 numbered lockout holes and a clear window so you can see the secured keys inside. The working principle is worth understanding: one isolation lock (the “equipment lock”) is applied to the energy source, and its key is placed inside the box. Every worker then applies their own personal lock to the box. The equipment cannot be re-energized until the last worker removes their personal lock and the isolation key is released. This keeps the relationship between the isolation lock key and each person’s lock clear, which is exactly what a multi-user LOTO procedure needs.
The table below uses specifications published on the individual Prolockey product pages. Jaw and lock-hole figures are the verified values; always re-confirm against your own padlocks and isolation points before purchase.
| Model | Body / Shackle Material | Max Padlocks (Lock Holes) | Jaw Opening | Lock-Hole Diameter | Notes |
|---|---|---|---|---|---|
| SH01 (steel) | PA body, nickel-plated steel shackle | 6 | 25 mm (1 in) or 38 mm (1.5 in) | 9.8 mm | Standard red group hasp |
| AH11 (aluminum) | Nylon body, aluminum shackle | 6 | 25 mm (1 in) or 38 mm (1.5 in) | 9 mm | Lightweight, spark-resistant |
| DSH01 (steel, double-end) | Red sprayed steel | 6 | 20.5 mm and 46 mm (two ends) | 11 mm | Clamps two isolation points at once |
| AH31 (sliding aluminum) | Anodized aluminum | 12 | 38.5 mm | 8 mm | Sliding hasp for larger crews |
| AH32 (sliding aluminum) | Anodized aluminum | 24 | 38.5 mm | 8 mm | High-capacity sliding hasp |
Even with the right product in hand, a few mistakes undermine a group LOTO procedure. Watch for these when you standardize hasps for your facility:
A lockout hasp holds as many padlocks as it has lock holes. A 6-hole hasp holds up to six personal locks, a 12-hole sliding hasp holds up to twelve, and a 24-hole sliding hasp holds up to twenty-four. The lock-hole count, not the jaw size, sets the capacity.
No. Jaw size only determines whether the hasp can clamp onto your isolation point. Padlock capacity is determined by the number of lock holes. You should size the jaw for fit and the lock holes for the number of workers separately.
A 6-hole hasp accepts up to six personal locks; an 8-hole hasp would accept up to eight. For crews larger than six, the practical option is the 12-hole sliding aluminum hasp (AH31) or the 24-hole sliding hasp (AH32), which give more capacity than a typical eight-lock need without a custom model. Hole diameter and jaw fit remain the other two checks.
Measure the shackle diameter of the padlocks your workers carry, then compare it to the hasp’s lock-hole diameter. The shackle should pass through the hole cleanly with little play. If your thickest in-use shackle exceeds the hole diameter, choose a hasp with a larger hole or match padlocks to the hasp.
If a single hasp runs out of holes, you can pair hasps, move to a higher-capacity sliding hasp (AH31 or AH32), or use a group lockout box such as the LK07. The box holds the isolation lock key while each worker locks the box with their own personal lock, so the equipment stays isolated until the last person leaves. Avoid improvising with unrelated locks or shared keys.
Measure the energy-isolating device you intend to lock, not the pipe or panel around it, and pick a jaw that passes over it but closes securely. Photograph the device with a ruler or reference object before ordering so the jaw size can be confirmed against your actual equipment.
Need help matching a hasp to your setup?
For model matching, provide the expected number of personal locks, the attachment-point dimensions, and your padlock shackle diameter. PROLOCKEY can help compare suitable hasp options.
Disclaimer: Prolockey provides lockout tagout devices; employers are responsible for establishing and implementing site-specific energy control procedures.
