Mary, be careful about pepper spray indoors. Everyone (including yourself) will most likely be incapacitated.

Although when I worked in the farms, we used teargas in the soil fumagant as a tracer (you'd know if there were any leaks), so most of my staff of field help was pretty much "immune" to tear gas / pepper spray. Yes, it still makes you cough and tear up, but most of those guys (and myself at the time) could still operate.

So, there could be a remote chance that an assailant could be somewhat more capable of continuing an assault despite your pepper spray (if they were on drugs, or highly motivated, or just plain stupid).

If you notice police successfully using pepper spray, there are always more police than perpetrators...