= Maximum safe load
{title2=$\mathrm{Lim}$}
The \b[maximum safe load] of a <weighing scale>, denoted $\mathrm{Lim}$, is the greatest static load it can carry without permanently changing its metrological qualities. This is the terminology of OIML R76-1:2006(E).<Non-automatic weighing instruments, Part 1>[T.3.1.7, printed p14]{ref} The definition concerns preservation of measurement behaviour, rather than merely whether the instrument remains visibly intact.
The <maximum weighing capacity> $\mathrm{Max}$ specifies a different property: the upper weighing capacity, excluding additive tare capacity. For an illustrative instrument marked $\mathrm{Max}=10\,\mathrm{kg}$ and $\mathrm{Lim}=15\,\mathrm{kg}$, a $12\,\mathrm{kg}$ static load is above the declared weighing capacity even though it is below the stated <maximum safe load>. The larger number does not extend the measurement range specified by $\mathrm{Max}$.<Non-automatic weighing instruments, Part 1>[T.3.1.1, printed p13; T.3.1.7, printed p14]{ref}
A simple model shows why metrological integrity is a stronger requirement than absence of breakage. Suppose a load permanently changes a mass indication from $r(m)=m$ to
$$
r_{\rm after}(m)=1.002m.
$$
The mechanism may still carry loads and return to an indicated zero, but a reference <mass> of $5\,\mathrm{kg}$ now indicates $5.01\,\mathrm{kg}$. In this invented example, the response has changed by $0.2\%$ without a zero offset. A <calibration> at nonzero loads would reveal that change; resetting a <zero-setting device> would not remove it.
The static qualification also matters. A falling object can impose a transient <force> different from its supported <gravitational weight>. A rating expressed through a static load therefore does not, by itself, specify response to an impact or a <crash pulse>.
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