Limit characters on essay survey questions

We use surveys as a way to ask people to complete forms such as nominations for our annual health and care awards. Using surveys has streamlined the nomination process and made things much easier for our team but one thing that would really help if is there was a way we could limit the text input on survey essay style questions. We ask people to provide reasons why they are nominating but we get so many entries we have to limit them to a 300 word limit. It would be so helpful if a word limit facility could be built into the survey tool.