Clear speaking and good hearing are needed to exchange information and instructions accurately — in person and by phone, sometimes loudly or quickly — and good visual acuity is needed for operating equipment, reading written or computer data, inspecting small details, checking the accuracy of work, and keeping an eye on your surroundings. You'll be working outdoors, so expect the full range of seasonal conditions: sun and heat (above 100 degrees for stretches of more than an hour), adverse weather, wetness and slippery surfaces, humidity, dust and dirt, fumes, insect bites and stings, garbage, and the other distractions that come with a park setting.