Does mercury chloride (ii) evaporate at room temperature?
According to this 1911 Journal of the American Chemical Society article (Johnson, F. M. G, JACS 1911, 33, 777), the vapor pressure of $\ce{HgCl2}$ is 3 mmHg at 152 degrees Celsius. Since the article is behind a paywall, I will reproduce the data below:

$$\begin{array}{|c|c|}
\hline
T/ \mathrm{^\circ C} &amp; P/ \mathrm{mmHg} \\ \hline
152 &amp; 3\\
195 &amp; 20 \\
231 &amp; 82 \\
256 &amp; 198\\
262 &amp; 237 \\
275 &amp; 325\\
278 &amp; 421 \\
283 &amp; 481\\
302 &amp; 754\\
\hline \end{array}$$

The authors did not report values for lower temperatures since their method focused on setting a pressure in the system and then measuring the temperature of sublimation/boiling point. However, using the data and some help from the Clausius-Clapeyron relationship, an estimate for the room temperature vapor pressure is $2.4\times 10^{-4}\ \mathrm{mmHg}$, which assuming you are at 1 atm, is 0.32 parts per million when the atmosphere is saturated. Consult a safety data sheet or other source for toxicity considerations at that exposure level.