How secure would a job as a sign language interpreter be?

this is a complicated question and the answer depends on many factors. I’m a sign language interpreter and so here’s what I can tell you.
There are 2 basic types of interprers – those who work in a K-12 school setting, and those who work in other settings. Your credentials and the whole testing process is different for each, as well as your job security. If you want to work in K-12 schools, the standard test nowadays is called the EIPA. If you work in a school where there’s a large deaf program with lots of students, your job will probably be pretty secure, and you will typically have the same benefits package that the support staff have. The pay depends on your EIPA level and where in the US you live. I would say the pay could range anywhere from $10 per hour up to $26 or so. (Maybe 13,000 per year up to 35,000 per year) Maybe more in someplace like Manhattan, DC, etc.. but keep in mind that you are only paid for part of the year based on the school calendar – maybe 180 days out of the year. If work in a school with only one or 2 deaf students, your job will not be as secure because once those students move to another school you will lose your job.

Ok lets now look at the second type of interpreter which is what I am. The standard for certification is the NIC test administered by the Registry of Interpreters for the Deaf (RID). There are 3 levels. Ceertified, Advanced, and Master. You can also work if you are not certified but will be paid less and will work less. So pay and security depend on many factors. Most interpreters are independent contractors, and don’t have any benefits through their job. Volume of work fluctuates. if you live in a large metropolitan area, you will get quite a bit of work if you’re certified, less if you aren’t. it takes a long time to become certified, and is going to require a BA degree by the year 2010. So you will need a BA plus several years experience to pass your tests. Only then will you have some level of security and a reasonable income. If you live in a rural area or anything other than a large metro area you will probably not get enough work to sustain yourself, but it might be a great second income if you’re married. So – rate of pay: again depends on your cert level. For free lance no benefits, range might be from $15 per hour for non certified up to $50 per hour for Master level certified doing legal interpreting. (again maybe more in high cost of living cities) Also you can charge more if you get your own contracts. The fees I quoted are your cut after your agency takes their cut. If you make your own contracts you can probably charge $60 per hour and up with a standard 2 hour minimum charge (that is standard in this industry). There are some agencies that hire staff interpreters with benefits for less hourly pay.
I live in Phoenix and I am on a salary with benefits. It’s 40,000 per year for working 30 hours per week. If I freelance I make around $40 per hour. There’s also VRS interpreting video phone calls. It’s more or less the same pay as above, and there are some VRS locations in medium size towns.
Lots of factors to think about, but the nuts and bolts of it are that you will hve more security and more money if you’re in a large city and if you’re nationally certified. Small town or uncertified and you will not make enough to support yourself.